3/25/07 – 3/31/07
by C. Zaitz
“Star light, star bright, first star I see tonight…” so which one will it be? People often ask, “what’s the first star?” or “what’s the biggest star?” or my personal favorite, “what’s the farthest star?” These questions tend to our desire to catalogue things, rank them, sort and classify. Maybe knowing the biggest, best, and brightest may be a way to make sense of the infinite and chaotic universe.
The problem with far away stars is that they are really hard to see! At the very limit of our view lie the most distant objects we can see; the quasars, with their light so stretched from the billions of years of travel that their spectra have migrated far into the red and infrared extremes. Quasars are strange objects; compact, bright and very distant. They seem to be the cores of ancient galaxies, most certainly with giant black holes at their centers. As of now, the farthest quasar we’ve found is nearly 13 billion light years away. That’s close to the time when we think the first stars and galaxies were forming. Before that, there was no light at all. So we’ll have to be content to say quasars are the farthest “objects” we can see.
What about big? All stars are big, compared to earth. Maybe you’ve heard that the sun a small star. In the great scheme of things, perhaps it’s not as big as, say, Betelgeuse or Deneb, but it’s just right for us. However, there are vast numbers of loftier and heftier stars than our own. Most of the bright stars in the sky would dwarf our sun. They are bright mainly because they are huge. We call the brightness of a star its magnitude. Stars have two magnitudes; the one we see, called the apparent magnitude, and the one it really is, called the absolute magnitude. Imagine trying to compare sizes of sailboats in a lake. It would be easy if they were all the same distance from you, but they’re all over the lake. You could classify them by how big they look, but that’s not really fair for the ones far away- they’ll always look tiny. Unfortunately, it’s very tricky to find the absolute magnitude of stars since they are scattered all over the universe. With sailboats, you might be able to recognize the type of boat by its appearance and infer its size from that knowledge, and that’s what we do with stars. But there’s room for error- what if the same brand of boat comes in 24’ and 32’ and they look very similar? Astronomers have several methods of estimating size and distance, but it’s not an exact science. So we’ll just say that Epsilon Aurigae, in the constellation of Auriga, is 2,700 times bigger than our sun, and that’s one of the biggest we’ve ever seen.
So how does one decide what the first star is? Are we looking for the first star that you see in the evening sky? This answer can be evasive, since the first star is usually a planet. Planets can be very bright, especially Venus. Venus has been greeting the sunset lately, and as twilight fades, its brilliance in the western sky is unparalleled. But it’s not a star. However, when you’re looking for the first of anything in the night sky, look for Venus. Its apparent magnitude is very great, and when it comes to just enjoying the night sky, appearances can be everything!
Until next week, my friends, enjoy the view.
Wednesday, March 21, 2007
Tuesday, March 13, 2007
What Goes Around
3/18/07 – 3/24/07
by C. Zaitz
I’ve been giving a series of planetarium shows for fourth graders. I’ve heard a lot of interesting things come out of ten year olds, but today they stumped me. I was pointing out the planets that are visible in the early evening. Venus hovers above the sunset, driving light daggers into your eyes as you watch the glow of the sun fade. Saturn, however, lags behind and is only just rising to a nice height at sunset. It is in the southeast, whereas Venus is definitely following the sun into the west.
I told the fourth graders that it was 8:30 at night and I showed them the two planets. Then I asked them where Venus would be by 10pm. They were a verbal group with stretch marks in their armpits from raising their hands so much. I assumed they would say that Venus would go down in the west, like the sun, moon and all the stars. It seemed like a safe question.
Not so. Among the answers I got were, “it will go to the north,” “it will go back to the east” and “it will go south.” I could not BRIBE them to say it went down in the west. So I asked them what was really moving when the sun went down.
We talked through the rotation of the earth and I told them that we are spinning at 800 mph in Michigan. I asked them why they thought we couldn’t feel that motion and we talked about the reasons, such as the fact that we’ve always been spinning on the big earth and as long as it doesn’t speed up or stop, we will never notice its motion. Then to top it all off, I basically pirouetted until I got dizzy to illustrate the motion of the earth. That was my big wind-up. Then I threw it back to them. With excited, baited breath I asked, “So where will Venus be in an hour, my young friends?” I was sure that my antics and explanations had done the trick. But it hadn’t. Not even close. Somehow those young minds had heard or read something that had confused them about the motion of sky objects. And I didn’t know how to undo it.
So I laughed it off and we moved on. Later on the time came to actually move the stars toward the west. I took the opportunity to try once more, so I pointed to Venus and had them watch it as it sank down into the western horizon. I think they saw it. They looked surprised, but I think they finally believed that Venus would follow the sun down in the west. Sometimes seeing is believing. I know that the concept of the earth spinning is pretty abstract, and ten year olds aren’t quite abstract thinkers yet, but I thought that they might have noticed things setting in the west. When I realized they may never have actually seen Venus in the sky, I got a little sad. So to all of you with kids, take them out this month and show them Venus. Just point yourself toward the west at sunset and you’ll see it, clouds willing. And if you have a few moments later on, spy on it again and see where it went. I’m pretty sure that it will have followed the sun down in the west. But it’s always good to see it for yourself.
Until next week, my friends, enjoy the view.
by C. Zaitz
I’ve been giving a series of planetarium shows for fourth graders. I’ve heard a lot of interesting things come out of ten year olds, but today they stumped me. I was pointing out the planets that are visible in the early evening. Venus hovers above the sunset, driving light daggers into your eyes as you watch the glow of the sun fade. Saturn, however, lags behind and is only just rising to a nice height at sunset. It is in the southeast, whereas Venus is definitely following the sun into the west.
I told the fourth graders that it was 8:30 at night and I showed them the two planets. Then I asked them where Venus would be by 10pm. They were a verbal group with stretch marks in their armpits from raising their hands so much. I assumed they would say that Venus would go down in the west, like the sun, moon and all the stars. It seemed like a safe question.
Not so. Among the answers I got were, “it will go to the north,” “it will go back to the east” and “it will go south.” I could not BRIBE them to say it went down in the west. So I asked them what was really moving when the sun went down.
We talked through the rotation of the earth and I told them that we are spinning at 800 mph in Michigan. I asked them why they thought we couldn’t feel that motion and we talked about the reasons, such as the fact that we’ve always been spinning on the big earth and as long as it doesn’t speed up or stop, we will never notice its motion. Then to top it all off, I basically pirouetted until I got dizzy to illustrate the motion of the earth. That was my big wind-up. Then I threw it back to them. With excited, baited breath I asked, “So where will Venus be in an hour, my young friends?” I was sure that my antics and explanations had done the trick. But it hadn’t. Not even close. Somehow those young minds had heard or read something that had confused them about the motion of sky objects. And I didn’t know how to undo it.
So I laughed it off and we moved on. Later on the time came to actually move the stars toward the west. I took the opportunity to try once more, so I pointed to Venus and had them watch it as it sank down into the western horizon. I think they saw it. They looked surprised, but I think they finally believed that Venus would follow the sun down in the west. Sometimes seeing is believing. I know that the concept of the earth spinning is pretty abstract, and ten year olds aren’t quite abstract thinkers yet, but I thought that they might have noticed things setting in the west. When I realized they may never have actually seen Venus in the sky, I got a little sad. So to all of you with kids, take them out this month and show them Venus. Just point yourself toward the west at sunset and you’ll see it, clouds willing. And if you have a few moments later on, spy on it again and see where it went. I’m pretty sure that it will have followed the sun down in the west. But it’s always good to see it for yourself.
Until next week, my friends, enjoy the view.
Wednesday, March 07, 2007
Moon Dust
by C. Zaitz
I’ve been thinking a lot lately about dust. Not just the dust that accumulates on the piano or the blinds. Not even the dust mixes with my shedding dog’s hair and ends up big as my fist, rolling across the hardwood floor. No, I’ve been thinking of far away dust, the kind of dust that sheaths the moon.
I have the privilege of working with some students who are involved in special projects. One student is trying to measure the electrical charge of dust that has been exposed to ultraviolet light. She chose this project because it seems that dust on the moon is very clingy. Astronauts who went to the moon and walked around got very dirty, very quickly. As soon as they stepped on the dust, it jumped onto their spacesuits and clung for dear life, almost as if the little dust particles had been waiting for billions of years for a ride to earth and finally it saw the opportunity. She wanted to see how charged dust can get, even here on earth. In that process we’ve both been learning a lot about dust. It’s not very sexy, but it’s pretty important.
Moon dust has some interesting properties. It’s not like the soft dust we find around the house. That dust is made of flakes of skin, pet dander, dirt particles and lint, among other things. Moon dust, however, is craggy and jagged. It’s made when asteroids hit the moon and pulverize rock. There’s nothing soft about moon dust. It’s so sharp that it cut through the seals on containers used to carry it back to earth. You wouldn’t want to step on a dust ball made of moon dust.
One of the problems with moon dust, and even dust on Mars, is that it tends to cling to everything. Scientists have different ideas why. One of the most popular ideas is something we experience all the time; static electricity, or better said, a difference in charges. Think of that dust that collects on your TV screen. The screen gets charged when it’s on, and the neutral dust gets attracted to it. Now think of the moon’s surface. Radiation from the sun knocks electrons off the dust and the particles become charged. Once an astronaut walks through the dust, the difference in charge makes the dust veritably leap onto the astronaut’s spacesuit. Since the dust is so caustic, in time it can cut and poke into the skin of the spacesuit, which is the only thing protecting the astronaut from certain death in the lunar environment. The dust is carried into the lunar lander and can get into sensitive equipment, with the potential of causing disaster.
Studies on how to combat the “stickiness” of the dust and the potential harm from it ended with the Apollo missions, but the rovers on Mars are still hampered by Martian dust as it covers their solar panels and gets into the working parts. It turns out that lowly dust can be a very important issue in future space travel. It could also be a key into understanding how the solar system formed, since current theories imply that the sun and planets coalesced out of space dust and gas. Dust has been around a long time. Perhaps with further study, we will know how to deal with moon dust by the time we get there in 2018. I know I wouldn’t want moon dust ruining my trip to the moon!
Until next week, my friends, enjoy the view.
I’ve been thinking a lot lately about dust. Not just the dust that accumulates on the piano or the blinds. Not even the dust mixes with my shedding dog’s hair and ends up big as my fist, rolling across the hardwood floor. No, I’ve been thinking of far away dust, the kind of dust that sheaths the moon.
I have the privilege of working with some students who are involved in special projects. One student is trying to measure the electrical charge of dust that has been exposed to ultraviolet light. She chose this project because it seems that dust on the moon is very clingy. Astronauts who went to the moon and walked around got very dirty, very quickly. As soon as they stepped on the dust, it jumped onto their spacesuits and clung for dear life, almost as if the little dust particles had been waiting for billions of years for a ride to earth and finally it saw the opportunity. She wanted to see how charged dust can get, even here on earth. In that process we’ve both been learning a lot about dust. It’s not very sexy, but it’s pretty important.
Moon dust has some interesting properties. It’s not like the soft dust we find around the house. That dust is made of flakes of skin, pet dander, dirt particles and lint, among other things. Moon dust, however, is craggy and jagged. It’s made when asteroids hit the moon and pulverize rock. There’s nothing soft about moon dust. It’s so sharp that it cut through the seals on containers used to carry it back to earth. You wouldn’t want to step on a dust ball made of moon dust.
One of the problems with moon dust, and even dust on Mars, is that it tends to cling to everything. Scientists have different ideas why. One of the most popular ideas is something we experience all the time; static electricity, or better said, a difference in charges. Think of that dust that collects on your TV screen. The screen gets charged when it’s on, and the neutral dust gets attracted to it. Now think of the moon’s surface. Radiation from the sun knocks electrons off the dust and the particles become charged. Once an astronaut walks through the dust, the difference in charge makes the dust veritably leap onto the astronaut’s spacesuit. Since the dust is so caustic, in time it can cut and poke into the skin of the spacesuit, which is the only thing protecting the astronaut from certain death in the lunar environment. The dust is carried into the lunar lander and can get into sensitive equipment, with the potential of causing disaster.
Studies on how to combat the “stickiness” of the dust and the potential harm from it ended with the Apollo missions, but the rovers on Mars are still hampered by Martian dust as it covers their solar panels and gets into the working parts. It turns out that lowly dust can be a very important issue in future space travel. It could also be a key into understanding how the solar system formed, since current theories imply that the sun and planets coalesced out of space dust and gas. Dust has been around a long time. Perhaps with further study, we will know how to deal with moon dust by the time we get there in 2018. I know I wouldn’t want moon dust ruining my trip to the moon!
Until next week, my friends, enjoy the view.
Wednesday, February 28, 2007
Astarte’s Crescent
3/4/07 – 3/10/07
by C. Zaitz
The crescent may very well be one of the most beautiful shapes of our lovely neighbor, the moon. The curved smile of the young moon after it has just passed through its shadowy new phase is a crowning jewel to twilight’s glorious robes of color, but sometimes that shadowy grin looks like a smirk, and sometimes a friendly smile.
Sometimes when you look at the crescent moon, it appears to look like the letter “C”, only backwards, more like a “D” without the straight part. But sometimes it looks like the letter “U,” or a birch bark canoe sailing over the horizon before it dips below the earth. I saw the moon looking like that last month, and I wondered about it.
It was an unusual sight. I wasn’t used to seeing the crescent moon in that position, and strangely I had just read an article about how the crescent moon looks like a “U” from latitudes near the equator. So why was our crescent moon looking like that, at our latitude, nearly halfway to the North Pole?
It’s true that near the equator, the crescent waxing moon looks more like a boat than a banana. It sets nearly straight down, chasing the sun to the ground. The sun does the same thing; near the equator the sun rises nearly straight up and sets the same way. In Michigan, we only see that on the vernal or autumnal equinoxes, when the sun crosses the celestial equator (an imaginary projection of earth’s equator onto the sky.) We remember that earth is tipped 23.5 degrees with respect to the plane of our orbit around the sun. If we project the plane of our orbit out into space and also the equator, these two circles cross at two points. One is in the spring, and the other is in autumn. We call these two days the equinoxes, and we are coming up on the Vernal or spring equinox. It’s at this time of year that the sun rises due east and sets due west. The moon’s orbit is only tipped about 5 degrees from the plane of our orbit, so it’s following that path pretty closely. So if the sun seems to rise and set straight up at this time of the year, it stands to reason that the young moon would as well. Thus we see our smiling moon.
In ancient times the crescent moon was the symbol of the Phoenicians goddess Astarte, known as Ishtar to the Mesopotamians, Diana to the Greeks and Venus to the Romans. Her “bediamonded crescent” was poetically captured by Edgar Allan Poe. You can see the crescent moon in modern times on flags and images from many different cultures. Muslim holidays and religious observances often start or end with the first sighting of the waxing crescent moon. The optimal conditions for sighting the young moon is when the angle that the moon sets is nearly perpendicular to the horizon, which happens to be around mid March for the Northern Hemisphere. The next young crescent moon will appear a few days after new moon, so look around the 19th or 20th of March to see if you can spot it. If you don’t see it one night, look the next. You’ll see the slim crescent grow, night after night, and be a witness to one of the more beautiful sights in the sky.
Until next week, my friends, enjoy the view.
by C. Zaitz
The crescent may very well be one of the most beautiful shapes of our lovely neighbor, the moon. The curved smile of the young moon after it has just passed through its shadowy new phase is a crowning jewel to twilight’s glorious robes of color, but sometimes that shadowy grin looks like a smirk, and sometimes a friendly smile.
Sometimes when you look at the crescent moon, it appears to look like the letter “C”, only backwards, more like a “D” without the straight part. But sometimes it looks like the letter “U,” or a birch bark canoe sailing over the horizon before it dips below the earth. I saw the moon looking like that last month, and I wondered about it.
It was an unusual sight. I wasn’t used to seeing the crescent moon in that position, and strangely I had just read an article about how the crescent moon looks like a “U” from latitudes near the equator. So why was our crescent moon looking like that, at our latitude, nearly halfway to the North Pole?
It’s true that near the equator, the crescent waxing moon looks more like a boat than a banana. It sets nearly straight down, chasing the sun to the ground. The sun does the same thing; near the equator the sun rises nearly straight up and sets the same way. In Michigan, we only see that on the vernal or autumnal equinoxes, when the sun crosses the celestial equator (an imaginary projection of earth’s equator onto the sky.) We remember that earth is tipped 23.5 degrees with respect to the plane of our orbit around the sun. If we project the plane of our orbit out into space and also the equator, these two circles cross at two points. One is in the spring, and the other is in autumn. We call these two days the equinoxes, and we are coming up on the Vernal or spring equinox. It’s at this time of year that the sun rises due east and sets due west. The moon’s orbit is only tipped about 5 degrees from the plane of our orbit, so it’s following that path pretty closely. So if the sun seems to rise and set straight up at this time of the year, it stands to reason that the young moon would as well. Thus we see our smiling moon.
In ancient times the crescent moon was the symbol of the Phoenicians goddess Astarte, known as Ishtar to the Mesopotamians, Diana to the Greeks and Venus to the Romans. Her “bediamonded crescent” was poetically captured by Edgar Allan Poe. You can see the crescent moon in modern times on flags and images from many different cultures. Muslim holidays and religious observances often start or end with the first sighting of the waxing crescent moon. The optimal conditions for sighting the young moon is when the angle that the moon sets is nearly perpendicular to the horizon, which happens to be around mid March for the Northern Hemisphere. The next young crescent moon will appear a few days after new moon, so look around the 19th or 20th of March to see if you can spot it. If you don’t see it one night, look the next. You’ll see the slim crescent grow, night after night, and be a witness to one of the more beautiful sights in the sky.
Until next week, my friends, enjoy the view.
Tuesday, February 20, 2007
Waltzing with Luna
2/25/07 – 3/3/07
C. Zaitz
Did you ever notice that when you gaze at the full moon, it always looks the same? It’s not just a round bland face; it has features. Some say it has a smile, or that the dark areas look like a bunny or frog or even an astronaut tickling the chin of a poodle. Next full moon, take a look and notice what you see. It’s what you’ve seen your entire life.
Maybe you don't miss the other side of the moon, but isn’t it odd that we never get to see it? It’s a sphere, so it must have other faces, but we only see the same one, over and over. In fact, no one had ever seen the back side of the moon until 1959, when we sent rockets around our cosmic companion. It turns out that the other side of the moon is very different from the side we see. There are no dark areas to make smiles or bunnies. It’s all “highlands,” with very few “maria,” the dark lava “seas” that make the shapes so familiar to us on our side of the moon.
Notice I didn’t say “dark side of the moon.” No offense to Pink Floyd, but technically it’s not correct to refer to the other side of the moon as the “dark side,” since over the course of a month it gets just as much sunlight as the side facing us.
So the question is: why do we see only one face of the moon? Is it because the moon isn’t rotating? Actually, with respect to the stars, it is rotating. If it didn’t rotate, over the course of the month we’d see all of it. It would slowly show each nook and crater to us. Instead, it rotates at the same speed that it circles us. This is called synchronous rotation, and it turns out that it is no accident. The majority of the moons in our solar system are synchronized with their parent planet. It’s all about tides.
We may remember that the moon tugs on the earth and creates tidal bulges in the oceans, but what we may not know is that even rocks and dirt feel the effects of that tug and experience tidal bulging. Tidal bulges occur in any body that is tugged on by other bodies. The result of these bulges is that they act like little friction brakes to the spin of the object. The moon is causing the earth to slow down. As a thank you, the earth is sending the moon farther away from us to conserve angular momentum. Meanwhile, the two are facing off like a bullfighter and his bull. The moon has already succumbed, but eventually, earth will slow enough so that one face will point eternally toward the moon as well. Then they will dance, staring each other down, until the sun itself burns out and goes dark.
This effect is called tidal locking, and is the opposite of rare in the solar system. Given enough time, most objects will have orbital and rotational resonance with their nearest gravitational partners. If that sounds like heavy duty physics, it is. But it’s also beautiful, because the whole system of planets, moons and the sun will be in sync, in a cosmic waltz, pirouetting at the same time, locked in eternal embraces. I wonder what the band will be playing for the dance. Perhaps it will be the music of the spheres.
Until next week, my friends, enjoy the view.
C. Zaitz
Did you ever notice that when you gaze at the full moon, it always looks the same? It’s not just a round bland face; it has features. Some say it has a smile, or that the dark areas look like a bunny or frog or even an astronaut tickling the chin of a poodle. Next full moon, take a look and notice what you see. It’s what you’ve seen your entire life.
Maybe you don't miss the other side of the moon, but isn’t it odd that we never get to see it? It’s a sphere, so it must have other faces, but we only see the same one, over and over. In fact, no one had ever seen the back side of the moon until 1959, when we sent rockets around our cosmic companion. It turns out that the other side of the moon is very different from the side we see. There are no dark areas to make smiles or bunnies. It’s all “highlands,” with very few “maria,” the dark lava “seas” that make the shapes so familiar to us on our side of the moon.
Notice I didn’t say “dark side of the moon.” No offense to Pink Floyd, but technically it’s not correct to refer to the other side of the moon as the “dark side,” since over the course of a month it gets just as much sunlight as the side facing us.
So the question is: why do we see only one face of the moon? Is it because the moon isn’t rotating? Actually, with respect to the stars, it is rotating. If it didn’t rotate, over the course of the month we’d see all of it. It would slowly show each nook and crater to us. Instead, it rotates at the same speed that it circles us. This is called synchronous rotation, and it turns out that it is no accident. The majority of the moons in our solar system are synchronized with their parent planet. It’s all about tides.
We may remember that the moon tugs on the earth and creates tidal bulges in the oceans, but what we may not know is that even rocks and dirt feel the effects of that tug and experience tidal bulging. Tidal bulges occur in any body that is tugged on by other bodies. The result of these bulges is that they act like little friction brakes to the spin of the object. The moon is causing the earth to slow down. As a thank you, the earth is sending the moon farther away from us to conserve angular momentum. Meanwhile, the two are facing off like a bullfighter and his bull. The moon has already succumbed, but eventually, earth will slow enough so that one face will point eternally toward the moon as well. Then they will dance, staring each other down, until the sun itself burns out and goes dark.
This effect is called tidal locking, and is the opposite of rare in the solar system. Given enough time, most objects will have orbital and rotational resonance with their nearest gravitational partners. If that sounds like heavy duty physics, it is. But it’s also beautiful, because the whole system of planets, moons and the sun will be in sync, in a cosmic waltz, pirouetting at the same time, locked in eternal embraces. I wonder what the band will be playing for the dance. Perhaps it will be the music of the spheres.
Until next week, my friends, enjoy the view.
Tuesday, February 13, 2007
Star-crossed Science
2/18/07 – 2/24/07
by C. Zaitz
I recently had a conversation with high school students about astrology. Astronomy and astrology have been around for thousands of years, but the science of astronomy only broke with the art of astrology a few hundred years ago. Astronomia was the old word for the scholars who undertook the duties of observing and predicting sky motions, interpreting them and applying them to earthly events. In fact, the observatories and salaries needed for observing and predicting (astronomy) were often paid for by the profits made by interpreting and applying (astrology).
Most of the great astronomers we can think of were also astrologers. There was no shame in casting horoscopes. In fact, it was quite a lucrative business for some. Johannes Kepler, known to scientists for his three Laws of Planetary Motion, was a prolific astrologer while he wasn’t trying to figure out the nature of things. When his paycheck didn’t arrive from his day job as a mathematician and astronomer, as it often didn’t, he resorted to casting natal charts and predicting events to feed his family. Kepler sometimes balked at mundane astrological duties, thinking that most common folk were too superstitious and ignorant to understand the true beauty of astrology. To him it was art married to science, it was real, and it meant something. It was a taste of the divine. Galileo, a contemporary of Kepler and famous for first gazing at the heavens through the newly developed telescope, also shared Kepler’s use of astrology. In fact, though some use Galileo as an example of one of the first scientists divorced from superstition, it’s much more likely that Galileo, like his contemporaries, viewed astrology as an aspect of religion and world view, where what happens above happens below, and that the heavens are reflected on earth. He cast horoscopes and charts like his contemporaries, when he wasn’t spying on the rings of Saturn or the moons of Jupiter.
The idea that earth is a reflection of the machinations of heaven is a beautiful thought, so it’s no wonder the notion has been around so long. But it began to lose favor in the mid 18th century. Why did astrology and astronomy split up? Perhaps because science and scientific methods became so important by making life better and for improving technology that people no longer wanted to rely on an “unscientific” form of prediction. Astrology became known as an occult or superstitious science, and the Age of Reason did not leave room for superstition. However, it didn’t go away completely, it just moved to the realm of divination.
Does that leave astrology without a foot hold in modern society? Many of us read our horoscopes in the newspaper for amusement, and some of us take it a bit more seriously. When I questioned the students about astrology, the vocal ones indicated that they thought it was somewhat silly. But the silent ones may have had different feelings that they were embarrassed to express in a science class. Nowadays it’s considered almost ignorant to believe in astrology. Yet, I don’t think humans will ever stop trying to make connections between what happens “below” and what might be happening “above.” And what better way than to watch the beautiful stars and planets? I almost admire people who find connections between the planets and their lives. I have never been able to, but wouldn’t it be fun to think that everything could be explained by looking at the stars?
Until next week, my friends, enjoy the view.
by C. Zaitz
I recently had a conversation with high school students about astrology. Astronomy and astrology have been around for thousands of years, but the science of astronomy only broke with the art of astrology a few hundred years ago. Astronomia was the old word for the scholars who undertook the duties of observing and predicting sky motions, interpreting them and applying them to earthly events. In fact, the observatories and salaries needed for observing and predicting (astronomy) were often paid for by the profits made by interpreting and applying (astrology).
Most of the great astronomers we can think of were also astrologers. There was no shame in casting horoscopes. In fact, it was quite a lucrative business for some. Johannes Kepler, known to scientists for his three Laws of Planetary Motion, was a prolific astrologer while he wasn’t trying to figure out the nature of things. When his paycheck didn’t arrive from his day job as a mathematician and astronomer, as it often didn’t, he resorted to casting natal charts and predicting events to feed his family. Kepler sometimes balked at mundane astrological duties, thinking that most common folk were too superstitious and ignorant to understand the true beauty of astrology. To him it was art married to science, it was real, and it meant something. It was a taste of the divine. Galileo, a contemporary of Kepler and famous for first gazing at the heavens through the newly developed telescope, also shared Kepler’s use of astrology. In fact, though some use Galileo as an example of one of the first scientists divorced from superstition, it’s much more likely that Galileo, like his contemporaries, viewed astrology as an aspect of religion and world view, where what happens above happens below, and that the heavens are reflected on earth. He cast horoscopes and charts like his contemporaries, when he wasn’t spying on the rings of Saturn or the moons of Jupiter.
The idea that earth is a reflection of the machinations of heaven is a beautiful thought, so it’s no wonder the notion has been around so long. But it began to lose favor in the mid 18th century. Why did astrology and astronomy split up? Perhaps because science and scientific methods became so important by making life better and for improving technology that people no longer wanted to rely on an “unscientific” form of prediction. Astrology became known as an occult or superstitious science, and the Age of Reason did not leave room for superstition. However, it didn’t go away completely, it just moved to the realm of divination.
Does that leave astrology without a foot hold in modern society? Many of us read our horoscopes in the newspaper for amusement, and some of us take it a bit more seriously. When I questioned the students about astrology, the vocal ones indicated that they thought it was somewhat silly. But the silent ones may have had different feelings that they were embarrassed to express in a science class. Nowadays it’s considered almost ignorant to believe in astrology. Yet, I don’t think humans will ever stop trying to make connections between what happens “below” and what might be happening “above.” And what better way than to watch the beautiful stars and planets? I almost admire people who find connections between the planets and their lives. I have never been able to, but wouldn’t it be fun to think that everything could be explained by looking at the stars?
Until next week, my friends, enjoy the view.
Monday, February 05, 2007
All This Useless Beauty
2/11/07 – 2/17/07
by C. Zaitz
Sometimes the sky overwhelms me. It is just so beautiful. When I run outside to let the dog out, the sky just catches me until I don’t know if it is the cold making my eyes tear up or if I’m really crying at the beauty.
That beauty is what caught me at a young age to want to know more about the Universe. I think the sky is rather like art. Sometimes you can look at a work of art and its beauty affects you, even if you don’t know anything about the artist or subject. However, when you look a little deeper, things really start to open up. Perhaps the first time you saw “Starry Night” by Vincent Van Gogh you thought, “well, that really doesn’t look like the sky at all!” But then you learn that he wasn’t really painting the sky so much as he was using images as a vehicle for his emotions and whirling thoughts. You begin to see the painting as an expression of impressions, and then you can understand the beauty of it on a different level.
For me, the beauty of the sky has inspired me to learn more. I think a pretty sunset over a gorgeous landscape can be just that, a pretty view. It can also be more. If you look into it, you can get a further appreciation of the magic of a sunset. You can learn how erupting volcanoes can make some of the most beautiful sunsets ever. But they can also extinguish life on earth.
When I was young and saw the moon through a telescope, things changed for me. The moon is positively scarred with craters from collisions with meteors and asteroids. I learned that the earth has been pummeled as well, even more than the Moon since it is larger. I no longer believed that the earth was a charmed planet, and that no asteroid would dare collide with MY planet! I guess I got a dose of reality.
It’s nice to look at the beauty of the earth, to watch the shows on the Nature Channel or even go hiking or boating to enjoy nature. But there has been a lot of talk lately about how we have changed our environment simply by thriving in it, by harnessing the energy of the earth in order to make our lives more secure and comfortable. Though there is debate about the extent of global warming and its timeline, there is a great amount of evidence telling us that we are affecting our environment in a way that is detrimental to our continuation as a species. It’s beautiful and awesome to watch huge chunks of Antarctic ice falling into the ocean. There’s a certain amount of inevitableness about it. I suppose that’s why we don’t lie awake worrying about asteroids hitting us. Yet we aren’t dinosaurs. We are capable of good and great things. But if all the beauty that inspires us doesn’t urge us to look deeper into what we’re doing, it might all go away. Or maybe we will. All this useless beauty, if we don’t read into it, if we don’t look a little deeper than the surface of the sunset, or the story of the moon. Useless beauty if we don’t take the time to understand ourselves and our environment. And it’s such a fascinating story!
Until next week, my friends, enjoy the view.
by C. Zaitz
Sometimes the sky overwhelms me. It is just so beautiful. When I run outside to let the dog out, the sky just catches me until I don’t know if it is the cold making my eyes tear up or if I’m really crying at the beauty.
That beauty is what caught me at a young age to want to know more about the Universe. I think the sky is rather like art. Sometimes you can look at a work of art and its beauty affects you, even if you don’t know anything about the artist or subject. However, when you look a little deeper, things really start to open up. Perhaps the first time you saw “Starry Night” by Vincent Van Gogh you thought, “well, that really doesn’t look like the sky at all!” But then you learn that he wasn’t really painting the sky so much as he was using images as a vehicle for his emotions and whirling thoughts. You begin to see the painting as an expression of impressions, and then you can understand the beauty of it on a different level.
For me, the beauty of the sky has inspired me to learn more. I think a pretty sunset over a gorgeous landscape can be just that, a pretty view. It can also be more. If you look into it, you can get a further appreciation of the magic of a sunset. You can learn how erupting volcanoes can make some of the most beautiful sunsets ever. But they can also extinguish life on earth.
When I was young and saw the moon through a telescope, things changed for me. The moon is positively scarred with craters from collisions with meteors and asteroids. I learned that the earth has been pummeled as well, even more than the Moon since it is larger. I no longer believed that the earth was a charmed planet, and that no asteroid would dare collide with MY planet! I guess I got a dose of reality.
It’s nice to look at the beauty of the earth, to watch the shows on the Nature Channel or even go hiking or boating to enjoy nature. But there has been a lot of talk lately about how we have changed our environment simply by thriving in it, by harnessing the energy of the earth in order to make our lives more secure and comfortable. Though there is debate about the extent of global warming and its timeline, there is a great amount of evidence telling us that we are affecting our environment in a way that is detrimental to our continuation as a species. It’s beautiful and awesome to watch huge chunks of Antarctic ice falling into the ocean. There’s a certain amount of inevitableness about it. I suppose that’s why we don’t lie awake worrying about asteroids hitting us. Yet we aren’t dinosaurs. We are capable of good and great things. But if all the beauty that inspires us doesn’t urge us to look deeper into what we’re doing, it might all go away. Or maybe we will. All this useless beauty, if we don’t read into it, if we don’t look a little deeper than the surface of the sunset, or the story of the moon. Useless beauty if we don’t take the time to understand ourselves and our environment. And it’s such a fascinating story!
Until next week, my friends, enjoy the view.
Wednesday, January 31, 2007
Baby Stars
2/4/07 – 2/10/07
by C. Zaitz
One of the most magnificent things to “see” in the sky is the Great Nebula in Orion. However, it’s not so great to the naked eye on a chilly evening in light-polluted Metro Detroit in February. Your eye might detect a little fuzziness, a little hazy area around the stars at the tip of Orion’s sword. One of the “stars” is really the nebula, but the significance of this little blur in the sky might be lost by a casual glance.
If we look a little deeper, the fuzzy blob reveals one of the most incredible places in our galaxy. The nebula is a huge, diffuse cloud of gas and dust, some 1,500 light years from earth. The nebula formed from an even more diffuse cloud of molecular gas, slowly brought together into denser pockets that eventually formed stars. We now see pockets of gas and dust forming bubbles, or protoplanetary discs. Perhaps stars with planets are forming, or maybe a double star system will form. We already see baby stars in their formative years. Embedded within the wisps of colorful gas of the nebula is a group of four hot, blue stars in a formation we call the Trapezium, at least one of which is a double star. These stars can be seen easily with a small telescope, and they mark the spot where nearly 1,000 sun-like stars are just being born and are beginning to shine. It’s a stellar nursery, similar to the famous one we’ve seen in the Eagle Nebula.
Right now the area is clouded with dust and gas, lit in abstract colors by the intense fires of the newly born stars. Astronomers say that eventually the nebula will be blown away or absorbed and what will be left is something similar to the Pleiades or the Beehive cluster. These are called open clusters, and remind me of ripe grapes hanging in clusters in space. They are beautiful, but they relatively devoid of the colorful gas clouds that make the Orion Nebula so stunning. When we look at the Nebula with telescopes and make long-exposure images, we see an incredibly breathtaking work of art, nature’s best, hanging low in the constellation of Orion.
So how do you go about seeing the Orion nebula? If you begin on the internet, by looking at the beautiful full-color shots from the Hubble Space telescope or even large ground-based telescopes, you will not be disappointed. But if you start there, you may end there. You may never get the thrill of seeing the nebula live, in person, through a telescope. And there is something special about seeing deep-space object, or things outside our solar system, with your own eyes. Therefore, finding a winter star party is your best bet for seeing the nebula. Amateur astronomers are famous for sharing their expensive telescopes with anyone who wants to see the sky, and even some folks who were just innocently passing by. I have even been known to cajole people into taking a glimpse. Though folks may be tentative at first, it only takes seconds to be converted into a believer.
Who is throwing a star party at this time of the year? If you do a quick internet search for our local amateur astronomy groups, you’ll be surprised. As long as you bundle up in layers, winter star gazing can be quite exhilarating and fun. And there’s oh so many ways to warm up afterwards, sharing laughs and warm beverages with new friends.
Until next week, my friends, enjoy the view.
by C. Zaitz
One of the most magnificent things to “see” in the sky is the Great Nebula in Orion. However, it’s not so great to the naked eye on a chilly evening in light-polluted Metro Detroit in February. Your eye might detect a little fuzziness, a little hazy area around the stars at the tip of Orion’s sword. One of the “stars” is really the nebula, but the significance of this little blur in the sky might be lost by a casual glance.
If we look a little deeper, the fuzzy blob reveals one of the most incredible places in our galaxy. The nebula is a huge, diffuse cloud of gas and dust, some 1,500 light years from earth. The nebula formed from an even more diffuse cloud of molecular gas, slowly brought together into denser pockets that eventually formed stars. We now see pockets of gas and dust forming bubbles, or protoplanetary discs. Perhaps stars with planets are forming, or maybe a double star system will form. We already see baby stars in their formative years. Embedded within the wisps of colorful gas of the nebula is a group of four hot, blue stars in a formation we call the Trapezium, at least one of which is a double star. These stars can be seen easily with a small telescope, and they mark the spot where nearly 1,000 sun-like stars are just being born and are beginning to shine. It’s a stellar nursery, similar to the famous one we’ve seen in the Eagle Nebula.
Right now the area is clouded with dust and gas, lit in abstract colors by the intense fires of the newly born stars. Astronomers say that eventually the nebula will be blown away or absorbed and what will be left is something similar to the Pleiades or the Beehive cluster. These are called open clusters, and remind me of ripe grapes hanging in clusters in space. They are beautiful, but they relatively devoid of the colorful gas clouds that make the Orion Nebula so stunning. When we look at the Nebula with telescopes and make long-exposure images, we see an incredibly breathtaking work of art, nature’s best, hanging low in the constellation of Orion.
So how do you go about seeing the Orion nebula? If you begin on the internet, by looking at the beautiful full-color shots from the Hubble Space telescope or even large ground-based telescopes, you will not be disappointed. But if you start there, you may end there. You may never get the thrill of seeing the nebula live, in person, through a telescope. And there is something special about seeing deep-space object, or things outside our solar system, with your own eyes. Therefore, finding a winter star party is your best bet for seeing the nebula. Amateur astronomers are famous for sharing their expensive telescopes with anyone who wants to see the sky, and even some folks who were just innocently passing by. I have even been known to cajole people into taking a glimpse. Though folks may be tentative at first, it only takes seconds to be converted into a believer.
Who is throwing a star party at this time of the year? If you do a quick internet search for our local amateur astronomy groups, you’ll be surprised. As long as you bundle up in layers, winter star gazing can be quite exhilarating and fun. And there’s oh so many ways to warm up afterwards, sharing laughs and warm beverages with new friends.
Until next week, my friends, enjoy the view.
Tuesday, January 23, 2007
Catch a Glimpse
1/28/07 – 2/3/07
by C. Zaitz
We have a somewhat rare opportunity to catch a glimpse of a planet that usually hides in the glow of the sun. Little planet Mercury should be visible in the western sunset glow until about the 7th of February. You’ll need a pretty flat western horizon and a little patience to see the diminutive and shy planet, but once you see him, you’ll never forget it.
Here’s why: as you look toward the west at sunset, you can see our entire inner solar system. Venus, shining brightly even a half hour after sunset, will be the first thing you notice. You can’t miss her; she is the brightest celestial object after the sun and moon. Venus dominates the sky after the sun goes down. She was named for the goddess of love and beauty, for the obvious reason of her glorious glow. She shines so brilliantly that she can be mistaken for man-made or even alien craft. If you watch her for a minute or two, you’ll notice her steady light. This is no plane or UFO, it's the brilliant evening "star."
Once you find Venus, you should look a little down and to the right to find Mercury. This planet was named for the fleet footed god of the Romans, Mercury. As the closest planet to the sun, his orbit is small and fast. He whips around the sun once every 88 days. But it’s not his speed that makes him hard to see, it’s the fact that the smallest of the planets is never very far from the sun. When you look for Mercury, you’ll have to balance waiting for the sun to be low enough for the skies to darken, but not waiting too long so that it sets. Don’t give up on Mercury, though- he’s worth the wait. Seeing Mercury is like the thrill of seeing a rare but hidden flower or bird.
Standing on planet Earth, third from the sun, we can skim past our own horizon, looking past our own atmosphere and see Venus and Mercury rushing in their trips around the sun. The inner solar system is very busy, and relatively close together and dense, just as when the solar system first formed. Most of the mass and heavy elements literally gravitated toward the middle. These inner planets are dense, fast and alone. No moons tag along to hinder the orbits of Mercury or Venus.
Further out, and seen later in the evening, are the giant planets Saturn and Jupiter, and even Mars. To see Saturn, you don’t have to wait too long after sunset. Look toward the east around 9pm and you’ll see the giant gas planet glowing near the constellation of Leo. Leo reminds me of a backwards question mark, but to see the whole constellation, you’ll have to wait up till midnight or so. As long as you’re up watching the skies, you might as well wait till morning, around 7am, when you can catch a glimpse of the last two planets of the night. Jupiter will be hanging low near the glow of sunrise, and planet Mars, dimly glowing, will be even closer to the horizon. But if you have a clear view of the east on your morning commute and catch a glimpse of these planets, you will have seen the entire visible solar system over the course of one night. What more could you ask for?
Until next week, my friends, enjoy the view.
by C. Zaitz
We have a somewhat rare opportunity to catch a glimpse of a planet that usually hides in the glow of the sun. Little planet Mercury should be visible in the western sunset glow until about the 7th of February. You’ll need a pretty flat western horizon and a little patience to see the diminutive and shy planet, but once you see him, you’ll never forget it.
Here’s why: as you look toward the west at sunset, you can see our entire inner solar system. Venus, shining brightly even a half hour after sunset, will be the first thing you notice. You can’t miss her; she is the brightest celestial object after the sun and moon. Venus dominates the sky after the sun goes down. She was named for the goddess of love and beauty, for the obvious reason of her glorious glow. She shines so brilliantly that she can be mistaken for man-made or even alien craft. If you watch her for a minute or two, you’ll notice her steady light. This is no plane or UFO, it's the brilliant evening "star."
Once you find Venus, you should look a little down and to the right to find Mercury. This planet was named for the fleet footed god of the Romans, Mercury. As the closest planet to the sun, his orbit is small and fast. He whips around the sun once every 88 days. But it’s not his speed that makes him hard to see, it’s the fact that the smallest of the planets is never very far from the sun. When you look for Mercury, you’ll have to balance waiting for the sun to be low enough for the skies to darken, but not waiting too long so that it sets. Don’t give up on Mercury, though- he’s worth the wait. Seeing Mercury is like the thrill of seeing a rare but hidden flower or bird.
Standing on planet Earth, third from the sun, we can skim past our own horizon, looking past our own atmosphere and see Venus and Mercury rushing in their trips around the sun. The inner solar system is very busy, and relatively close together and dense, just as when the solar system first formed. Most of the mass and heavy elements literally gravitated toward the middle. These inner planets are dense, fast and alone. No moons tag along to hinder the orbits of Mercury or Venus.
Further out, and seen later in the evening, are the giant planets Saturn and Jupiter, and even Mars. To see Saturn, you don’t have to wait too long after sunset. Look toward the east around 9pm and you’ll see the giant gas planet glowing near the constellation of Leo. Leo reminds me of a backwards question mark, but to see the whole constellation, you’ll have to wait up till midnight or so. As long as you’re up watching the skies, you might as well wait till morning, around 7am, when you can catch a glimpse of the last two planets of the night. Jupiter will be hanging low near the glow of sunrise, and planet Mars, dimly glowing, will be even closer to the horizon. But if you have a clear view of the east on your morning commute and catch a glimpse of these planets, you will have seen the entire visible solar system over the course of one night. What more could you ask for?
Until next week, my friends, enjoy the view.
Wednesday, January 17, 2007
More Than Meets the Eye, Part II
1/21/07 – 1/27/07
by C. Zaitz
It’s hard to watch the birth of a star. Apparently stars like to form in private, shrouded by opaque clouds of gas and dust. When giant molecular clouds in space collapse from their own gravity, one outcome is a star with planets. Often, rather than planets, two or more stars form. Scientists wonder what causes one and not the other, but stars pull a self-made curtain around themselves during their birthing. With better telescopes, however, we’re beginning to see more. Over half the stars in the sky are multiple star systems. Here’s what we can see.
Sometimes we can detect a system of two stars, called binary stars, through spectroscopy. This is the study of the light we collect from them. Normally we can spread the light we collect from stars out into a spectrum so we can learn all manner of things about the star; its composition, perhaps its distance, speed and direction, and even how old it is. It’s amazing what a little starlight can do. But sometimes we notice that the spectrum from a star is odd. Part of it is shifted toward the blue end of the spectrum, and part toward the red. Shifting of spectra is a curious thing; it tells us that the star is both coming toward us and away from us. Impossible! Unless, perhaps, it’s not just one star, but two stars in orbit, with one coming toward us and one going away. In fact, this is how we discover many binary stars.
Sometimes we see stars dimming and brightening, apparently for no reason. However, as adults, we recognize that things usually have reasons, as bizarre as they may be. Sometimes when stars orbit each other, they happen to be in our line of sight such that they will eclipse each other. They are known as eclipsing binaries. One star, in the constellation Perseus, is a very famous eclipsing binary star. Algol is normally about 2.3 magnitude, easily seen with the naked eye, but every 10 hours or so it will dim about 68%. This is when its companion moves in front of our line of sight, Since the companion star is dimmer, the total amount of light we get from Algol lessens. Perhaps that’s why it is named in Arabic, “the ghoul.” Algol is often referred to as the winking eye of the demon.
If a star has several companions, it becomes a star system. A famous system of stars is the middle star in the handle of the Big Dipper. Just using your eyes, you can usually detect two stars instead of one. Mizar and Alcor are close, but not close enough to be a double star system. We call that a visual binary- they appear close in the sky, but are not that close physically. However, the brighter of the two, Mizar, is actually composed of two stars, Mizar A and Mizar B. Furthermore, Mizar A is composed of two stars, as is Mizar B, so we have a system of two sets of twins orbiting each other. Amazing. But you can’t see this with your eyes. It’s fun to look at Mizar and Alcor anyway and imagine the complicated gavotte those stars must be executing.
Look to the north to see the Big Dipper, and if your eye is caught by a shiny light in the west at sunset, don’t be alarmed. It’s only the eye-catching, attention hogging Venus, showing off in the fading twilight.
Until next week, my friends, enjoy the view.
by C. Zaitz
It’s hard to watch the birth of a star. Apparently stars like to form in private, shrouded by opaque clouds of gas and dust. When giant molecular clouds in space collapse from their own gravity, one outcome is a star with planets. Often, rather than planets, two or more stars form. Scientists wonder what causes one and not the other, but stars pull a self-made curtain around themselves during their birthing. With better telescopes, however, we’re beginning to see more. Over half the stars in the sky are multiple star systems. Here’s what we can see.
Sometimes we can detect a system of two stars, called binary stars, through spectroscopy. This is the study of the light we collect from them. Normally we can spread the light we collect from stars out into a spectrum so we can learn all manner of things about the star; its composition, perhaps its distance, speed and direction, and even how old it is. It’s amazing what a little starlight can do. But sometimes we notice that the spectrum from a star is odd. Part of it is shifted toward the blue end of the spectrum, and part toward the red. Shifting of spectra is a curious thing; it tells us that the star is both coming toward us and away from us. Impossible! Unless, perhaps, it’s not just one star, but two stars in orbit, with one coming toward us and one going away. In fact, this is how we discover many binary stars.
Sometimes we see stars dimming and brightening, apparently for no reason. However, as adults, we recognize that things usually have reasons, as bizarre as they may be. Sometimes when stars orbit each other, they happen to be in our line of sight such that they will eclipse each other. They are known as eclipsing binaries. One star, in the constellation Perseus, is a very famous eclipsing binary star. Algol is normally about 2.3 magnitude, easily seen with the naked eye, but every 10 hours or so it will dim about 68%. This is when its companion moves in front of our line of sight, Since the companion star is dimmer, the total amount of light we get from Algol lessens. Perhaps that’s why it is named in Arabic, “the ghoul.” Algol is often referred to as the winking eye of the demon.
If a star has several companions, it becomes a star system. A famous system of stars is the middle star in the handle of the Big Dipper. Just using your eyes, you can usually detect two stars instead of one. Mizar and Alcor are close, but not close enough to be a double star system. We call that a visual binary- they appear close in the sky, but are not that close physically. However, the brighter of the two, Mizar, is actually composed of two stars, Mizar A and Mizar B. Furthermore, Mizar A is composed of two stars, as is Mizar B, so we have a system of two sets of twins orbiting each other. Amazing. But you can’t see this with your eyes. It’s fun to look at Mizar and Alcor anyway and imagine the complicated gavotte those stars must be executing.
Look to the north to see the Big Dipper, and if your eye is caught by a shiny light in the west at sunset, don’t be alarmed. It’s only the eye-catching, attention hogging Venus, showing off in the fading twilight.
Until next week, my friends, enjoy the view.
Wednesday, January 10, 2007
More Than Meets the Eye, Part I
1/14/07 – 1/20/07
by C. Zaitz
One of the more interesting facts about the night sky is that most of the stars you can see are not alone. Though they look like single points of light, there’s more than meets the naked eye. Some stars have companions that are too dim and small to see, and some have planets which are too dim and small to see. Either way, there is much more going on than we realize with those distant stars.
Our sun is one star that happens to sport planets. Planets are the result of a process that is not completely understood, so I will give you the short version, leaving out details in favor of getting the bigger picture.
A long, long time ago there was a cloud of gas and dust, the remnants of a star that once used to shine, but had long ago blown itself to bits and had created heavy elements in the process. This cloud was unimaginably huge, and all the little bits of it were moving in some direction. Eventually, the muddled bits tended to go in one direction in particular, flattened out, colliding and growing together under the force of gravity. Most of the bits came together in a great ball, which eventually became so massive that the inner bits were crushed and made to fuse, causing a chain reaction that produced prodigious amounts of energy. The sun was born.
Meanwhile, there was a still a great disk of gas and dust further out. The heavier stuff, like rocks and dirt and gold and silver, tended to be nearer the middle, forming the rocky inner planets. The lighter stuff, like hydrogen and helium and other wispy gases, collected further out in great blobs we call the gas giant planets. The little inner planets were heavy and cleaned up their orbits pretty well. Of the four planets, there are only three moons. Earth’s moon is the only respectable looking satellite, since Mars has two overgrown potatoes orbiting it.
Beyond Mars and the asteroids, things get more complicated. The four gassy planets developed rings and multiple moons. The rings are like millions of tiny, shattered ice moons. Some of the moons, and even some planets, have odd scars and orbits which indicate violent collisions, and possibly intense gravitational wars which have shaped the outer solar system. Recently, we have discovered a host of small bodies beyond Neptune which are now called dwarf planets. Pluto is of this realm, but more Pluto-like bodies are being discovered all the time.
As we look to other stars, we notice that a few hundred seem to have bodies orbiting them. These bodies are huge compared to our planets, but not big enough to be stars. Better telescopes will surely reveal smaller, more earth-like planets around stars. In fact, some astronomers estimate that nearly half the stars in the sky have planets. That’s a lot of planets. I wonder what those planets are like. Some are probably rocky and small like our earth. Will they house aliens? Will we someday meet Klingons? Or maybe the truth will be stranger than fiction. The exciting part is that someday we may be able to answer the question: are there aliens living on other planets. I hope the answer isn’t “no.” How dull!
Next week we will explore the strange multiple star systems that can also form instead of planets.
Until next week, my friends, enjoy the view.
by C. Zaitz
One of the more interesting facts about the night sky is that most of the stars you can see are not alone. Though they look like single points of light, there’s more than meets the naked eye. Some stars have companions that are too dim and small to see, and some have planets which are too dim and small to see. Either way, there is much more going on than we realize with those distant stars.
Our sun is one star that happens to sport planets. Planets are the result of a process that is not completely understood, so I will give you the short version, leaving out details in favor of getting the bigger picture.
A long, long time ago there was a cloud of gas and dust, the remnants of a star that once used to shine, but had long ago blown itself to bits and had created heavy elements in the process. This cloud was unimaginably huge, and all the little bits of it were moving in some direction. Eventually, the muddled bits tended to go in one direction in particular, flattened out, colliding and growing together under the force of gravity. Most of the bits came together in a great ball, which eventually became so massive that the inner bits were crushed and made to fuse, causing a chain reaction that produced prodigious amounts of energy. The sun was born.
Meanwhile, there was a still a great disk of gas and dust further out. The heavier stuff, like rocks and dirt and gold and silver, tended to be nearer the middle, forming the rocky inner planets. The lighter stuff, like hydrogen and helium and other wispy gases, collected further out in great blobs we call the gas giant planets. The little inner planets were heavy and cleaned up their orbits pretty well. Of the four planets, there are only three moons. Earth’s moon is the only respectable looking satellite, since Mars has two overgrown potatoes orbiting it.
Beyond Mars and the asteroids, things get more complicated. The four gassy planets developed rings and multiple moons. The rings are like millions of tiny, shattered ice moons. Some of the moons, and even some planets, have odd scars and orbits which indicate violent collisions, and possibly intense gravitational wars which have shaped the outer solar system. Recently, we have discovered a host of small bodies beyond Neptune which are now called dwarf planets. Pluto is of this realm, but more Pluto-like bodies are being discovered all the time.
As we look to other stars, we notice that a few hundred seem to have bodies orbiting them. These bodies are huge compared to our planets, but not big enough to be stars. Better telescopes will surely reveal smaller, more earth-like planets around stars. In fact, some astronomers estimate that nearly half the stars in the sky have planets. That’s a lot of planets. I wonder what those planets are like. Some are probably rocky and small like our earth. Will they house aliens? Will we someday meet Klingons? Or maybe the truth will be stranger than fiction. The exciting part is that someday we may be able to answer the question: are there aliens living on other planets. I hope the answer isn’t “no.” How dull!
Next week we will explore the strange multiple star systems that can also form instead of planets.
Until next week, my friends, enjoy the view.
Thursday, January 04, 2007
Sitting in
I sat in with Jay and guest at last friday's broadcast, live Journal. It was pretty darn fun. A(No longer) archived on the WHFR on the website in the bottom right corner under "WHFR Journal Podcast Archive." (only the latest epsiode is there... but stay tuned, I'll try to get it all here one day) I knitted a bunch and they made me laugh. Well worth it! I giggled through the whole thing.
Pretty Pleiades
1/7/07 – 1/13/07
by C. Zaitz
The Pleiades are so very pretty and interesting that they deserve some attention. You might know them as the Seven Sisters or might not know their name, but you’ve probably noticed them in the winter sky. They are often confused with the little dipper, but they are much tinier. In suburbia they are ephemeral, but if you are patient you can usually spot them in a cloudless sky. They are definitely worth knowing about, so let’s get to know them a little better.
The Pleiadian sisters are famous. Many cultures have seen and even worshipped the Pleiades, though they have been called many things in many languages. They rise in the east before Orion the Hunter, and he chases them across the sky all evening. The sister stars have even more mythological starry sisters, known as the Hyades. You may have noticed them as well, if you’ve seen the “v” shape of stars to the west of Orion. Look for Orion’s shiny belt of three stars and point up from there to find them. The “v” marks the face of Taurus, and the brightest star marks his eye. This star is named Aldebaran, which in Arabic means “the one who follows.” Aldebaran is not one of the Hyades, but the rest of the stars are. Some say the Seven Sisters are being chased by Orion, since the mighty hunter was notorious for having an eye for the ladies. If so, Orion will have to wait a very long time. The Pleiades are “running fast.”
Though they are often called “the Seven Sisters,” the faint group of stars is what we call an “open cluster” of many more than seven stars. Over 200 stars are collected in an area of space some 10-30 light years across. That is pretty dense compared to most of space, but open clusters are still less dense than the ancient globular clusters of stars we also find in the outskirts of galaxies. The Pleiades are known as the brightest open cluster of stars in the sky. Though they are not quite as pretty, the Hyades are much closer, “only” 130 light years away. The Pleiades are well over 400. If they were as close as the Hyades, imagine how spectacular they would be in our night sky!
The Pleiades were the daughters of Atlas, the man who was forced to carry the weight of the world on his shoulders, and Pleione, a sea nymph. The daughters all had beautiful Greek names: Maia, Electra, Taygete, Alcyone, Celaeno, Sterope, and Merope. Maia was the mother of Hermes by Zeus himself, and all the sisters except Merope consorted with gods. Merope was wooed by Orion and is said to have married Sisyphus. Since she was not of the immortal realm, her star faded. Some say that is why we can only make out six of the seven stars today.
Scientifically we know that the stars are receding from us, and eventually we may have difficulty in seeing any of the sisters with the naked eye, but until then, please enjoy them with binoculars, or just with your eyes. You can see the pretty stars all winter long.
Until next week, my friends, enjoy the view.
by C. Zaitz
The Pleiades are so very pretty and interesting that they deserve some attention. You might know them as the Seven Sisters or might not know their name, but you’ve probably noticed them in the winter sky. They are often confused with the little dipper, but they are much tinier. In suburbia they are ephemeral, but if you are patient you can usually spot them in a cloudless sky. They are definitely worth knowing about, so let’s get to know them a little better.
The Pleiadian sisters are famous. Many cultures have seen and even worshipped the Pleiades, though they have been called many things in many languages. They rise in the east before Orion the Hunter, and he chases them across the sky all evening. The sister stars have even more mythological starry sisters, known as the Hyades. You may have noticed them as well, if you’ve seen the “v” shape of stars to the west of Orion. Look for Orion’s shiny belt of three stars and point up from there to find them. The “v” marks the face of Taurus, and the brightest star marks his eye. This star is named Aldebaran, which in Arabic means “the one who follows.” Aldebaran is not one of the Hyades, but the rest of the stars are. Some say the Seven Sisters are being chased by Orion, since the mighty hunter was notorious for having an eye for the ladies. If so, Orion will have to wait a very long time. The Pleiades are “running fast.”
Though they are often called “the Seven Sisters,” the faint group of stars is what we call an “open cluster” of many more than seven stars. Over 200 stars are collected in an area of space some 10-30 light years across. That is pretty dense compared to most of space, but open clusters are still less dense than the ancient globular clusters of stars we also find in the outskirts of galaxies. The Pleiades are known as the brightest open cluster of stars in the sky. Though they are not quite as pretty, the Hyades are much closer, “only” 130 light years away. The Pleiades are well over 400. If they were as close as the Hyades, imagine how spectacular they would be in our night sky!
The Pleiades were the daughters of Atlas, the man who was forced to carry the weight of the world on his shoulders, and Pleione, a sea nymph. The daughters all had beautiful Greek names: Maia, Electra, Taygete, Alcyone, Celaeno, Sterope, and Merope. Maia was the mother of Hermes by Zeus himself, and all the sisters except Merope consorted with gods. Merope was wooed by Orion and is said to have married Sisyphus. Since she was not of the immortal realm, her star faded. Some say that is why we can only make out six of the seven stars today.
Scientifically we know that the stars are receding from us, and eventually we may have difficulty in seeing any of the sisters with the naked eye, but until then, please enjoy them with binoculars, or just with your eyes. You can see the pretty stars all winter long.
Until next week, my friends, enjoy the view.
Wednesday, December 27, 2006
Time in a Bottle
12/31/06 – 1/6/06
by C. Zaitz
I’ve been thinking about time. I celebrated Christmas with my parents in Adams Basin, New York. Adams Basin is a little cross roads, but it has a tiny Post Office, a church, and a Little Red Schoolhouse. It is also recognized as the place where George Washington’s drummer boy was buried. In 1976 I was a little Brownie Girl Scout, marching in the Bicentennial parade, when America celebrated 200 years as a nation. We stopped at the little hill cemetery where the crooked slabs of marble poked out of the ground like broken teeth. People who had lived so long ago were buried there, their names long since erased by rain and wind. I grew up in an old house where the land was rich with buried bottles of different colors and shapes that would turn up every spring after roto-tilling. Every time we’d find a bottle, it was an exciting link to the past and the history of the little burg.
This past year I have learned a lot about time and different ways to think about it. Geology has taught me that time can be read like a mystery novel. Rock and dirt layers write the past in paragraphs of time, with overlapping plots and buried clues, like my bottles. Astronomy often depicts time as an arrow. The point of the arrow is in your brain, and the feathers are at the object whose light you are seeing. Locally, time’s arrow is straight and true, traveling only in one direction, from past to present to future. The Second Law of Thermodynamics is an expression of how we all feel about time- it tends to flow, like heat or energy, from concentrated to spread out, like light leaving the sun.
However, we have found that gravity and speed can change time, as Einstein’s Theory of General Relativity has stated. Traveling at nearly the speed of light can really slow down time for you. So can getting too close to the gravity of a black hole. If you were standing at a distance watching someone “fall in” to a black hole, they would appear to slow down and stop right at the edge, and you’d never actually see them fall in due to the stretching of time. Apparently time can be touched, time can be changed. Time is perceived.
My education courses reminded me that time must be used wisely, as teachers have a lot of work to do in a short period of time. Organization and planning must be the tools of an effective teacher, or an effective person. In this case, time is a commodity, and we are always trying to buy more. Sometimes we all need a mini black hole to slow down time for us.
On a personal note, this year has been one full of changes for me, from job loss to full time school and training, and now I will begin student teaching. I am grateful to those of you who have expressed support for the work I do in astronomy outreach, both by writing and by teaching in the planetarium. It is the one thing I hold on to through all the changes, and if I could keep the warm feelings I get from sharing astronomy in a bottle, I would, but since the only way to really “keep” moments of time is to share them, I will continue to do so as long as I can.
Until next week, my friends, enjoy the view.
by C. Zaitz
I’ve been thinking about time. I celebrated Christmas with my parents in Adams Basin, New York. Adams Basin is a little cross roads, but it has a tiny Post Office, a church, and a Little Red Schoolhouse. It is also recognized as the place where George Washington’s drummer boy was buried. In 1976 I was a little Brownie Girl Scout, marching in the Bicentennial parade, when America celebrated 200 years as a nation. We stopped at the little hill cemetery where the crooked slabs of marble poked out of the ground like broken teeth. People who had lived so long ago were buried there, their names long since erased by rain and wind. I grew up in an old house where the land was rich with buried bottles of different colors and shapes that would turn up every spring after roto-tilling. Every time we’d find a bottle, it was an exciting link to the past and the history of the little burg.
This past year I have learned a lot about time and different ways to think about it. Geology has taught me that time can be read like a mystery novel. Rock and dirt layers write the past in paragraphs of time, with overlapping plots and buried clues, like my bottles. Astronomy often depicts time as an arrow. The point of the arrow is in your brain, and the feathers are at the object whose light you are seeing. Locally, time’s arrow is straight and true, traveling only in one direction, from past to present to future. The Second Law of Thermodynamics is an expression of how we all feel about time- it tends to flow, like heat or energy, from concentrated to spread out, like light leaving the sun.
However, we have found that gravity and speed can change time, as Einstein’s Theory of General Relativity has stated. Traveling at nearly the speed of light can really slow down time for you. So can getting too close to the gravity of a black hole. If you were standing at a distance watching someone “fall in” to a black hole, they would appear to slow down and stop right at the edge, and you’d never actually see them fall in due to the stretching of time. Apparently time can be touched, time can be changed. Time is perceived.
My education courses reminded me that time must be used wisely, as teachers have a lot of work to do in a short period of time. Organization and planning must be the tools of an effective teacher, or an effective person. In this case, time is a commodity, and we are always trying to buy more. Sometimes we all need a mini black hole to slow down time for us.
On a personal note, this year has been one full of changes for me, from job loss to full time school and training, and now I will begin student teaching. I am grateful to those of you who have expressed support for the work I do in astronomy outreach, both by writing and by teaching in the planetarium. It is the one thing I hold on to through all the changes, and if I could keep the warm feelings I get from sharing astronomy in a bottle, I would, but since the only way to really “keep” moments of time is to share them, I will continue to do so as long as I can.
Until next week, my friends, enjoy the view.
Tuesday, December 19, 2006
Circle of Stars
12/24/06 – 12/30/06
by C.Zaitz
What a lovely time of year to see the stars. It’s always been said that winter stargazing is the best stargazing of all. The sky is dark right after dinner, and is lazy to get bright again the next morning, giving us the longest nights of the year. With our mild winter so far, it’s not such a task to spend a few minutes looking heaven-ward.
What’s up there to see? Looking south, you’ll see the “wreath” - seven stars that form a ring in the winter sky. Some call it the “winter circle.” It’s so sparkly bright, I like to think of it as a wreath of candles sparkling all night long. Four of these seven stars are in the top ten list of bright stars of all time.
Let’s start with the Bull’s eye. Though it’s only the 13th brightest in the sky, it’s a noticeable star. Aldebaran is the name of the pink-tinged eye of Taurus, the Bull. Since we’re starting our circle with this star, let’s be sure we know which one it is. Use the three stars of Orion’s belt, from east to west, to make an arrow that points up to it. It’s the top star of a V-shape of stars, outlining the face of Taurus. From there, you can look back at Orion’s foot, a bright blue-white star called Rigel, from the Arabic ar-rijl, “the foot.” That’s one hot foot! Rigel is much hotter than our own sun, and the 7th brightest in the sky. Now we are going clockwise around the circle, and the next stop is the most serious one of all. It’s Sirius, the number one brightest star in the whole night sky. Sirius is also nick-named “the dog star” due to its position as the wet, shiny nose of Canis Major, the big dog. Now we are east of Orion, and can look up from Sirius to another bright star in a dog constellation. This time it’s the little dog, Canis Minor. The star’s name is Procyon, which means “before the dog” referring to the fact that Procyon rises slightly before Sirius, the dog star. It’s the 8th brightest star in the sky.
We are halfway around, and the next two stars are the Twins. Castor and Pollux, the twin boys of the god Zeus disguised as a swan, and Leda. The two stars are inseparable, just as the twins were during their life, so the stories go. At the top of the circle is a bright star called Capella. It’s very high up in the sky, and it is the 6th brightest star in the sky. Its name means “she-goat.” It is part of a constellation named “Auriga” which sounds a little like Orion, who is just below him. Auriga is a Charioteer, but he is holding baby goats in his arms, known as “the kids.” They are a cute little triangle of faint stars near Capella, who must then be the Momma goat.
And then there’s the famous star Betelgeuse, though it lies more toward the middle of the circle. It is the 10th brightest star in the sky. As the shoulder (or more literally, “armpit”) of Orion, it shouldn’t be forgotten in our winter stargazing.
I hope you enjoy the embracing wreath of winter stars, as you enjoy the embraces of family and friends this holiday. Joy and peace to you all!
Until next week, my friends, enjoy the view.
Here's a website with a good depiction of the Winter Circle.
by C.Zaitz
What a lovely time of year to see the stars. It’s always been said that winter stargazing is the best stargazing of all. The sky is dark right after dinner, and is lazy to get bright again the next morning, giving us the longest nights of the year. With our mild winter so far, it’s not such a task to spend a few minutes looking heaven-ward.
What’s up there to see? Looking south, you’ll see the “wreath” - seven stars that form a ring in the winter sky. Some call it the “winter circle.” It’s so sparkly bright, I like to think of it as a wreath of candles sparkling all night long. Four of these seven stars are in the top ten list of bright stars of all time.
Let’s start with the Bull’s eye. Though it’s only the 13th brightest in the sky, it’s a noticeable star. Aldebaran is the name of the pink-tinged eye of Taurus, the Bull. Since we’re starting our circle with this star, let’s be sure we know which one it is. Use the three stars of Orion’s belt, from east to west, to make an arrow that points up to it. It’s the top star of a V-shape of stars, outlining the face of Taurus. From there, you can look back at Orion’s foot, a bright blue-white star called Rigel, from the Arabic ar-rijl, “the foot.” That’s one hot foot! Rigel is much hotter than our own sun, and the 7th brightest in the sky. Now we are going clockwise around the circle, and the next stop is the most serious one of all. It’s Sirius, the number one brightest star in the whole night sky. Sirius is also nick-named “the dog star” due to its position as the wet, shiny nose of Canis Major, the big dog. Now we are east of Orion, and can look up from Sirius to another bright star in a dog constellation. This time it’s the little dog, Canis Minor. The star’s name is Procyon, which means “before the dog” referring to the fact that Procyon rises slightly before Sirius, the dog star. It’s the 8th brightest star in the sky.
We are halfway around, and the next two stars are the Twins. Castor and Pollux, the twin boys of the god Zeus disguised as a swan, and Leda. The two stars are inseparable, just as the twins were during their life, so the stories go. At the top of the circle is a bright star called Capella. It’s very high up in the sky, and it is the 6th brightest star in the sky. Its name means “she-goat.” It is part of a constellation named “Auriga” which sounds a little like Orion, who is just below him. Auriga is a Charioteer, but he is holding baby goats in his arms, known as “the kids.” They are a cute little triangle of faint stars near Capella, who must then be the Momma goat.
And then there’s the famous star Betelgeuse, though it lies more toward the middle of the circle. It is the 10th brightest star in the sky. As the shoulder (or more literally, “armpit”) of Orion, it shouldn’t be forgotten in our winter stargazing.
I hope you enjoy the embracing wreath of winter stars, as you enjoy the embraces of family and friends this holiday. Joy and peace to you all!
Until next week, my friends, enjoy the view.
Here's a website with a good depiction of the Winter Circle.
Wednesday, December 13, 2006
Light of the World
12/17/06 – 12/23/06
by C. Zaitz
I’ll admit it right now, I think I’m in the throes of SAD, the seasonal affect disorder, or at the very least, I’m pining after sunlight. Usually I love to see all the lights and decorations at this time of year. I have strings of “stars” hanging in my porch, twinkling on and off, and my neighbors have decorated with strings and strings of colored lights, wicker light-covered deer that appear to graze, and those blow-up Santas and snow-globe scenes. Perhaps I’ve grown cynical, but sometimes it all seems like too much.
Light can be good, but too much of anything can be bad. We live in a place where bigger seems to be better, where we want more of everything. I have a neighbor who has pretty much covered every square inch of her front yard with some glowing bit of plastic or twinkling light. Sure, it makes your mouth gape, but a little of the surprise and wonder is tinged with horror, as we remember the energy dials clicking and our hard earned money flying right up to the sky. So this year, I’m wondering if we can all spend a moment or two thinking about the ways we can avoid wasting resources. At the risk of sounding like Scrooge crossed with the Grinch, I wish we could tone down the outer displays and work on our inner lights, spreading around cheer and goodwill in a more personal way.
That’s a tall order, especially for someone like me who is pining for cheer and light. But think of the benefits of being able to walk out on your front porch with your kids and point to the Pleiades, that beautiful little cluster of stars that hangs on the edge of visibility in our light polluted skies. Or to be able to see Polaris, the North Star, and talk about who might be standing under the North Star at this time of year, working hard for all the good little girls and boys. Polaris is not a very bright star, and can be washed out by our street lights. It is the end star of the Little Dipper, but most of the stars of the Little Dipper are also washed out by light pollution.
I’m not suggesting we turn off all our lights; that would be sad. But perhaps we can resist the urge to “outdo” our neighbors and find other ways to show our Christmas spirit. Here’s something you can share with your neighbors as you are coming in from your long days of working, shopping, and surviving. See if you can find Orion’s belt in the sky, use a finger to draw a line up from the lowest star, straight across the three stars and beyond, until you find another bright star in a V-shaped group. This star is named Aldebaran. It’s the eye of Taurus, the Bull. On Taurus’ back ride the Pleiades (usually pronounced PLEE-a-dees), the little cluster of stars I mentioned. If you have a pair of binoculars, take the time to look through them. I predict you will be delighted. They are prettier than any diamonds in the jewelry store, and they have a lot of history and mythology associated with them. Sharing that with your family can be priceless!
I wish you all a very merry and cheery holiday season, with or without lights, but mostly I wish you peace and happiness.
Until next week, my friends, enjoy the view.
by C. Zaitz
I’ll admit it right now, I think I’m in the throes of SAD, the seasonal affect disorder, or at the very least, I’m pining after sunlight. Usually I love to see all the lights and decorations at this time of year. I have strings of “stars” hanging in my porch, twinkling on and off, and my neighbors have decorated with strings and strings of colored lights, wicker light-covered deer that appear to graze, and those blow-up Santas and snow-globe scenes. Perhaps I’ve grown cynical, but sometimes it all seems like too much.
Light can be good, but too much of anything can be bad. We live in a place where bigger seems to be better, where we want more of everything. I have a neighbor who has pretty much covered every square inch of her front yard with some glowing bit of plastic or twinkling light. Sure, it makes your mouth gape, but a little of the surprise and wonder is tinged with horror, as we remember the energy dials clicking and our hard earned money flying right up to the sky. So this year, I’m wondering if we can all spend a moment or two thinking about the ways we can avoid wasting resources. At the risk of sounding like Scrooge crossed with the Grinch, I wish we could tone down the outer displays and work on our inner lights, spreading around cheer and goodwill in a more personal way.
That’s a tall order, especially for someone like me who is pining for cheer and light. But think of the benefits of being able to walk out on your front porch with your kids and point to the Pleiades, that beautiful little cluster of stars that hangs on the edge of visibility in our light polluted skies. Or to be able to see Polaris, the North Star, and talk about who might be standing under the North Star at this time of year, working hard for all the good little girls and boys. Polaris is not a very bright star, and can be washed out by our street lights. It is the end star of the Little Dipper, but most of the stars of the Little Dipper are also washed out by light pollution.
I’m not suggesting we turn off all our lights; that would be sad. But perhaps we can resist the urge to “outdo” our neighbors and find other ways to show our Christmas spirit. Here’s something you can share with your neighbors as you are coming in from your long days of working, shopping, and surviving. See if you can find Orion’s belt in the sky, use a finger to draw a line up from the lowest star, straight across the three stars and beyond, until you find another bright star in a V-shaped group. This star is named Aldebaran. It’s the eye of Taurus, the Bull. On Taurus’ back ride the Pleiades (usually pronounced PLEE-a-dees), the little cluster of stars I mentioned. If you have a pair of binoculars, take the time to look through them. I predict you will be delighted. They are prettier than any diamonds in the jewelry store, and they have a lot of history and mythology associated with them. Sharing that with your family can be priceless!
I wish you all a very merry and cheery holiday season, with or without lights, but mostly I wish you peace and happiness.
Until next week, my friends, enjoy the view.
Wednesday, December 06, 2006
The Elusive Green Stars
12/10/06 – 12/16/06
by C. Zaitz
Stars come in different colors. We’ve all heard about “red giants” and “white dwarfs”, blue hot stars and orange cool stars. But what about green stars? Where are all the green stars? Our streets and houses are lit up this time of year with lights of red, blue, purple, green, orange and yellow. The stars come in those colors too, all but green. So what’s wrong with green stars?
Green is a great color. It's my mom’s favorite color, so I usually buy her clothes with green in them to make her happy. Green is the color of life, of plants and trees. Grass bleeds green when you cut it, and to me the color even "smells" like freshly cut grass. Green is the color of ”go” and avocados, girl scouts and money. Green is great. But not in stars. Our sun radiates energy mostly in the green part of the spectrum, so technically it would be a green star, if stars could look green. But they can’t. Why not?
Remember Roy G. Biv? Scientists have done away with color indigo for the most part, so it could be shortened to Roy Gbv, but that’s not as memorable, and hard to pronounce. Roy is the red end of the spectrum, and Biv is the blue end. Green is right in the middle of the light spectrum, and that is the problem. We can easily see when a star’s energy peaks in the red end of the spectrum. Most of the light we can see is reddish, so these cooler stars often appear red, even to the naked eye. The star Betelgeuse in the right shoulder of Orion is a classic red giant star. Very hot stars can peak in the blue end of the spectrum, giving them a bluish-white cast. The star diagonal from Betelgeuse in Orion’s left foot is called Rigel, and it is a very large, hot, bluish star. When you compare the tint of these two stars in the sky, it’s pretty easy to see the difference. However, since green is smack dab in the middle of the spectrum, when a star sends out most of its radiation in that wavelength, it is also sending out almost as much in the adjacent wavelengths. So all the colors- the reds, greens and blues- all mix together and make white. If we looked at our sun from above the atmosphere it would look white. In the sky it often appears yellow, or even red near the horizon. This is not because the sun has changed color. It is because the air is scattering blue light to make the sky blue, and the color that’s left when you take light blue out of white is yellow. Later on, as the light from the sun has to pass through a lot of atmosphere at sunset, most of the blue light has been scattered out of the sunlight, and only the long reddish wavelengths are left, giving us really rich sunsets.
If you want to see pretty Betelgeuse and bright Rigel, wait a little while after sunset, and you will see the three bright stars of Orion’s Belt. They are, from east to west, Alnitak, Alnilam, and Mintaka. Betelgeuse is above Alnitak, and Rigel is below Mintaka. All three stars in the belt are white-blue stars, very hot and very big. You can look for a green star among the thousands up there, but unless you’re wearing green-tinted glasses, you won’t find one!
Until next week, my friends, enjoy the view.
by C. Zaitz
Stars come in different colors. We’ve all heard about “red giants” and “white dwarfs”, blue hot stars and orange cool stars. But what about green stars? Where are all the green stars? Our streets and houses are lit up this time of year with lights of red, blue, purple, green, orange and yellow. The stars come in those colors too, all but green. So what’s wrong with green stars?
Green is a great color. It's my mom’s favorite color, so I usually buy her clothes with green in them to make her happy. Green is the color of life, of plants and trees. Grass bleeds green when you cut it, and to me the color even "smells" like freshly cut grass. Green is the color of ”go” and avocados, girl scouts and money. Green is great. But not in stars. Our sun radiates energy mostly in the green part of the spectrum, so technically it would be a green star, if stars could look green. But they can’t. Why not?
Remember Roy G. Biv? Scientists have done away with color indigo for the most part, so it could be shortened to Roy Gbv, but that’s not as memorable, and hard to pronounce. Roy is the red end of the spectrum, and Biv is the blue end. Green is right in the middle of the light spectrum, and that is the problem. We can easily see when a star’s energy peaks in the red end of the spectrum. Most of the light we can see is reddish, so these cooler stars often appear red, even to the naked eye. The star Betelgeuse in the right shoulder of Orion is a classic red giant star. Very hot stars can peak in the blue end of the spectrum, giving them a bluish-white cast. The star diagonal from Betelgeuse in Orion’s left foot is called Rigel, and it is a very large, hot, bluish star. When you compare the tint of these two stars in the sky, it’s pretty easy to see the difference. However, since green is smack dab in the middle of the spectrum, when a star sends out most of its radiation in that wavelength, it is also sending out almost as much in the adjacent wavelengths. So all the colors- the reds, greens and blues- all mix together and make white. If we looked at our sun from above the atmosphere it would look white. In the sky it often appears yellow, or even red near the horizon. This is not because the sun has changed color. It is because the air is scattering blue light to make the sky blue, and the color that’s left when you take light blue out of white is yellow. Later on, as the light from the sun has to pass through a lot of atmosphere at sunset, most of the blue light has been scattered out of the sunlight, and only the long reddish wavelengths are left, giving us really rich sunsets.
If you want to see pretty Betelgeuse and bright Rigel, wait a little while after sunset, and you will see the three bright stars of Orion’s Belt. They are, from east to west, Alnitak, Alnilam, and Mintaka. Betelgeuse is above Alnitak, and Rigel is below Mintaka. All three stars in the belt are white-blue stars, very hot and very big. You can look for a green star among the thousands up there, but unless you’re wearing green-tinted glasses, you won’t find one!
Until next week, my friends, enjoy the view.
Wednesday, November 29, 2006
What's on the Radio?
12/3/06 – 12/9/06
by C. Zaitz
We’ve all seen the dish. They have popped up like mushrooms all over the place. Even colleges and universities have them. However, some dishes that look like TV satellite dishes may actually be radio telescopes. They collect radio waves from the universe. I know that sounds funny, as if you could hear the universe on your radio, but I should clarify. Radio waves are very different from the sounds coming from your radio.
When we point big dishes up to the sky, even a satellite TV dish, we are collecting electromagnetic radiation in the form of radio waves. These are very long waves that can pass through our bodies without as much as a tingle. One wave can be as long as a city block, or as short as your shoe size. The radio station you listen to has to change electronic signals into carrier waves, which travel through the air. When these waves, which are flying all over the place harmlessly, get to the tuner in your radio, they are changed back into a signal that is amplified and modified. These signals produce vibrations on a speaker in your radio. It’s the sound pressure waves from the speaker going in and out quickly that reach your ear and your brain interprets as Mozart or Green Day. Pretty cool.
Sound waves cannot travel in space, since they need a medium (air) to vibrate in order to travel. The beauty of radio waves is that all they need is the original energy source that set them off. They can travel from one end of the universe to the other. Sure, they’ll lose some energy if they travel a long way, but we can still collect them if we have a big enough dish. That’s why we build giant radio dishes. One of the most famous ones was built in an old meteor crater in Arecibo, Puerto Rico. Nature hollowed out a big hole for us, and we stuck a dish in it and collect radio waves from all sorts of interesting objects.
Another cool thing about radio waves is that they can penetrate clouds and dust. Many other wavelengths, like much of the infrared and ultraviolet waves, as well as gamma and X-rays, are blocked by our atmosphere. But radio waves can go through clouds, even clouds of dust in space. Light can’t do that, so our picture of the universe in radio waves can sometimes be clearer than optical images. So what do we look at in radio waves?
The sun is a great producer of radio waves. In radio wavelengths, we see sunspots and solar flares that we might not see in visible light. Beyond the sun, there are stars and galaxies that produce radio waves. In fact, some objects emit more energy in radio waves than in light, so radio astronomy has opened up a new window on the universe. Galaxies that emitted strongly in the radio spectrum were the first clues to finding black holes and quasars. The Cosmic Background Radiation, the lynchpin in the theory of the Big Bang, was discovered by radio technology back in the 1960’s. Radio astronomy is still going strong today, and since radio dishes are relatively inexpensive and easy to build, even some schools and amateur astronomy clubs have them. So the next time your hear about a radio telescope, you’ll know that they are looking at, not listening to, the universe!
Until next week, my friends, enjoy the view.
by C. Zaitz
We’ve all seen the dish. They have popped up like mushrooms all over the place. Even colleges and universities have them. However, some dishes that look like TV satellite dishes may actually be radio telescopes. They collect radio waves from the universe. I know that sounds funny, as if you could hear the universe on your radio, but I should clarify. Radio waves are very different from the sounds coming from your radio.
When we point big dishes up to the sky, even a satellite TV dish, we are collecting electromagnetic radiation in the form of radio waves. These are very long waves that can pass through our bodies without as much as a tingle. One wave can be as long as a city block, or as short as your shoe size. The radio station you listen to has to change electronic signals into carrier waves, which travel through the air. When these waves, which are flying all over the place harmlessly, get to the tuner in your radio, they are changed back into a signal that is amplified and modified. These signals produce vibrations on a speaker in your radio. It’s the sound pressure waves from the speaker going in and out quickly that reach your ear and your brain interprets as Mozart or Green Day. Pretty cool.
Sound waves cannot travel in space, since they need a medium (air) to vibrate in order to travel. The beauty of radio waves is that all they need is the original energy source that set them off. They can travel from one end of the universe to the other. Sure, they’ll lose some energy if they travel a long way, but we can still collect them if we have a big enough dish. That’s why we build giant radio dishes. One of the most famous ones was built in an old meteor crater in Arecibo, Puerto Rico. Nature hollowed out a big hole for us, and we stuck a dish in it and collect radio waves from all sorts of interesting objects.
Another cool thing about radio waves is that they can penetrate clouds and dust. Many other wavelengths, like much of the infrared and ultraviolet waves, as well as gamma and X-rays, are blocked by our atmosphere. But radio waves can go through clouds, even clouds of dust in space. Light can’t do that, so our picture of the universe in radio waves can sometimes be clearer than optical images. So what do we look at in radio waves?
The sun is a great producer of radio waves. In radio wavelengths, we see sunspots and solar flares that we might not see in visible light. Beyond the sun, there are stars and galaxies that produce radio waves. In fact, some objects emit more energy in radio waves than in light, so radio astronomy has opened up a new window on the universe. Galaxies that emitted strongly in the radio spectrum were the first clues to finding black holes and quasars. The Cosmic Background Radiation, the lynchpin in the theory of the Big Bang, was discovered by radio technology back in the 1960’s. Radio astronomy is still going strong today, and since radio dishes are relatively inexpensive and easy to build, even some schools and amateur astronomy clubs have them. So the next time your hear about a radio telescope, you’ll know that they are looking at, not listening to, the universe!
Until next week, my friends, enjoy the view.
Wednesday, November 22, 2006
How’s the Weather?
11/26/06 – 12/2/06
by C. Zaitz
It’s the time of year when people start wondering about El Nino and what kind of winter we’re going to have. When I was younger, I would roll my eyes when my parents would ask, "how's the weather." Now, because I’m six hours due west of them, it’s fun to see how long it takes our weather to get to Rochester, New York. Weather tends to move from northwest to east in the United States. What Canada brings us, we send along to them, with a little Ontario “lake effect snow” for excitement.
If we lived on the western side of Michigan, we’d get lake effect snow as well. ”Lake effect” happens as air moves over a large body of water and picks up warmth and water vapor. As the air moves onto land, it cools off. Cooler air can’t hold as much humidity as warmer air, so it precipitates out and falls as snow. Our weather in Metro Detroit has to cross the whole Michigan Mitten before it reaches us, and by then it’s had time to dry out. Our snow fall is much more reasonable than snowfall in Traverse City, since it’s the lee shore of the lakes that gets the brunt of lake effect snow, sometimes spectacularly. I remember some awesome snowstorms and school closings growing up.
Nowadays there’s talk about El Nino. Simply put, it’s a combination of ocean and air changes that effect climate in a far-reaching area. If the Pacific Ocean has a higher than normal near-surface temperature for an extended period of time, it causes climate changes not only across North America, but around the globe. The combination of the warmer ocean along with changes it produces in air currents cause circulation to change, trade winds to alter, and weather reflects the changes.
The west coast may get more rain, and the Midwest can be drier during an El Nino period. But in Michigan, we get a milder winter. I’m not complaining. By now you’ve probably guessed I’m not a fan of snow, storms, or clouds. After growing up with lake effect snow and bad sinuses, I long for hot, dry and sunny. I’d be happy if I never had to blow my nose again. But it seems with El Nino and the effects of global warming, Michigan just might be the place to be. Folks in California may be under water, along with the east coast. The Midwest will be on fire, but in Michigan, we’re sitting pretty. Michigan may be the new Georgia.
I don’t mean to make light of a serious situation, but the more we learn about the earth’s climate systems, the more we should be ready for changes. We have already seen rising global temperatures over the past decade, and carbon dioxide levels in the atmosphere currently surpass any we’ve seen in the last 650,000 years. If a lot of volcanoes happen to erupt in the next decades, we’re sunk! It won’t be a giant asteroid that does us in, it will be our proclivity for spouting CO2 into the air. Google “Venus” if you want to see what happens next.
Speaking of Venus, she’s going to make her return to the evening twilight in December, so keep your eyes peeled for her bright orb to appear near the sunset as the month wears on.
Until next week, my friends, enjoy the view.
by C. Zaitz
It’s the time of year when people start wondering about El Nino and what kind of winter we’re going to have. When I was younger, I would roll my eyes when my parents would ask, "how's the weather." Now, because I’m six hours due west of them, it’s fun to see how long it takes our weather to get to Rochester, New York. Weather tends to move from northwest to east in the United States. What Canada brings us, we send along to them, with a little Ontario “lake effect snow” for excitement.
If we lived on the western side of Michigan, we’d get lake effect snow as well. ”Lake effect” happens as air moves over a large body of water and picks up warmth and water vapor. As the air moves onto land, it cools off. Cooler air can’t hold as much humidity as warmer air, so it precipitates out and falls as snow. Our weather in Metro Detroit has to cross the whole Michigan Mitten before it reaches us, and by then it’s had time to dry out. Our snow fall is much more reasonable than snowfall in Traverse City, since it’s the lee shore of the lakes that gets the brunt of lake effect snow, sometimes spectacularly. I remember some awesome snowstorms and school closings growing up.
Nowadays there’s talk about El Nino. Simply put, it’s a combination of ocean and air changes that effect climate in a far-reaching area. If the Pacific Ocean has a higher than normal near-surface temperature for an extended period of time, it causes climate changes not only across North America, but around the globe. The combination of the warmer ocean along with changes it produces in air currents cause circulation to change, trade winds to alter, and weather reflects the changes.
The west coast may get more rain, and the Midwest can be drier during an El Nino period. But in Michigan, we get a milder winter. I’m not complaining. By now you’ve probably guessed I’m not a fan of snow, storms, or clouds. After growing up with lake effect snow and bad sinuses, I long for hot, dry and sunny. I’d be happy if I never had to blow my nose again. But it seems with El Nino and the effects of global warming, Michigan just might be the place to be. Folks in California may be under water, along with the east coast. The Midwest will be on fire, but in Michigan, we’re sitting pretty. Michigan may be the new Georgia.
I don’t mean to make light of a serious situation, but the more we learn about the earth’s climate systems, the more we should be ready for changes. We have already seen rising global temperatures over the past decade, and carbon dioxide levels in the atmosphere currently surpass any we’ve seen in the last 650,000 years. If a lot of volcanoes happen to erupt in the next decades, we’re sunk! It won’t be a giant asteroid that does us in, it will be our proclivity for spouting CO2 into the air. Google “Venus” if you want to see what happens next.
Speaking of Venus, she’s going to make her return to the evening twilight in December, so keep your eyes peeled for her bright orb to appear near the sunset as the month wears on.
Until next week, my friends, enjoy the view.
Wednesday, November 15, 2006
In the Twinkle of a Star
11/19/06 – 11/26/06
by C. Zaitz
Have you ever wondered why the stars twinkle? We all know the song by heart, but it never really tells us why they twinkle, twinkle. The song wonders what they are, the little twinkling stars. I don’t want to ruin the song for anyone, but there are answers to both questions.
We don’t have to go very far to study a star. There’s one about 8 minutes away (going at the speed of light, of course). Traveling 70 mph, it would take us 1,328,571 hours, or 55,357 days, or 152 years!
Luckily we don’t have to go there. We can collect information from the sun just by standing outside with a telescope or other device to collect its light. The information we gather tells us the story of the Sun. It’s a middle-aged star, fusing hydrogen atoms in its core to produce enough energy and light to keep its planets warm and cozy. Well, not all its planets, just the lucky closer ones.
All stars are giant collections of atoms, mostly hydrogen. Stars are so mammoth that the great pressures near their centers allow for normally repulsive forces to be overcome and for atoms to fuse into new elements like oxygen and carbon. In fact, without the stars’ atom-fusing abilities, we’d have been a pretty boring universe of hydrogen and helium with a sprinkling of lithium for spice. No mercury, gold or silver. They came later, from stars.
So when you look up at the stars, you can think of them as giant element-producing ovens, getting very hot from churning out planet-making elements like silicon and nitrogen, stuff that ends up as sand and air. Think of that next time you’re on the beach, looking at the pretty sunset. It all came from some star, ancestor to our own sun.
While we’re at the beach, we can also figure out why stars twinkle. Just look into the water. See how the pebbles on the bottom seem to jump and hop around as the waves wash over them? The water is the medium that the light must travel through to get to our eyes. Light likes to go straight in a vacuum, but will change speed or direction in thicker stuff, like air or water, especially if they are moving. The water at the beach is moving a lot, so the pebbles seem to jump around madly. The air is also moving and therefore “bending” light, but not as much, since it is much less dense than water.
However, there is much more air above us than below us. There is a veritable ocean of air above us, and we must look through this “ocean” to see the stars. The starlight may have been traveling in the vacuum of space for millions of years, steady and true, all the way to earth. But when it gets to our atmosphere, it gets jostled, nudged and pushed around by moving air currents. By the time we get to see it, starlight can be jumping around like a drop of water on a hot frying pan. In winter, the atmosphere is often more turbulent, so you will see lots of twinkling and winking of starlight. It’s annoying in a telescope, but can be very pretty to the naked eye. So while you’re humming the song, you can enjoy the very distant stars twinkling and making someone a new beach!
Until next week, my friends, enjoy the view.
by C. Zaitz
Have you ever wondered why the stars twinkle? We all know the song by heart, but it never really tells us why they twinkle, twinkle. The song wonders what they are, the little twinkling stars. I don’t want to ruin the song for anyone, but there are answers to both questions.
We don’t have to go very far to study a star. There’s one about 8 minutes away (going at the speed of light, of course). Traveling 70 mph, it would take us 1,328,571 hours, or 55,357 days, or 152 years!
Luckily we don’t have to go there. We can collect information from the sun just by standing outside with a telescope or other device to collect its light. The information we gather tells us the story of the Sun. It’s a middle-aged star, fusing hydrogen atoms in its core to produce enough energy and light to keep its planets warm and cozy. Well, not all its planets, just the lucky closer ones.
All stars are giant collections of atoms, mostly hydrogen. Stars are so mammoth that the great pressures near their centers allow for normally repulsive forces to be overcome and for atoms to fuse into new elements like oxygen and carbon. In fact, without the stars’ atom-fusing abilities, we’d have been a pretty boring universe of hydrogen and helium with a sprinkling of lithium for spice. No mercury, gold or silver. They came later, from stars.
So when you look up at the stars, you can think of them as giant element-producing ovens, getting very hot from churning out planet-making elements like silicon and nitrogen, stuff that ends up as sand and air. Think of that next time you’re on the beach, looking at the pretty sunset. It all came from some star, ancestor to our own sun.
While we’re at the beach, we can also figure out why stars twinkle. Just look into the water. See how the pebbles on the bottom seem to jump and hop around as the waves wash over them? The water is the medium that the light must travel through to get to our eyes. Light likes to go straight in a vacuum, but will change speed or direction in thicker stuff, like air or water, especially if they are moving. The water at the beach is moving a lot, so the pebbles seem to jump around madly. The air is also moving and therefore “bending” light, but not as much, since it is much less dense than water.
However, there is much more air above us than below us. There is a veritable ocean of air above us, and we must look through this “ocean” to see the stars. The starlight may have been traveling in the vacuum of space for millions of years, steady and true, all the way to earth. But when it gets to our atmosphere, it gets jostled, nudged and pushed around by moving air currents. By the time we get to see it, starlight can be jumping around like a drop of water on a hot frying pan. In winter, the atmosphere is often more turbulent, so you will see lots of twinkling and winking of starlight. It’s annoying in a telescope, but can be very pretty to the naked eye. So while you’re humming the song, you can enjoy the very distant stars twinkling and making someone a new beach!
Until next week, my friends, enjoy the view.
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