9/2/07 – 9/8/07
C. Zaitz
I’ve been thinking about quantum mechanics lately. QM is a branch of physics that deals with the universe on the scale of the very small. On a daily basis, we don’t enter the realm of quantum mechanics, but more and more, scientists are finding that the properties of the very small scale inform the universe on a very big scale. And it’s a quite different universe on the small scale.
On the scale of the tiny, basic laws of “classical” physics break down. We are used to measuring things and describing their positions with numbers. In the realm of atoms, measuring things becomes impossible. You may have heard of Heisenberg’s Uncertainty Principle, the idea that you cannot know both the position and the momentum of an electron orbiting the nucleus of an atom. You can know where an electron is likely to be, but you can’t pinpoint it. The act of doing so would destroy the information you were trying to get. Once you “stop” the electron to study it, you have changed its momentum. And you cannot get around this fact. The measuring and the measured thing are entangled, you cannot separate them. We can intuit that perhaps more easily than other aspects of QM. In art, we say that “negative space” is as important as the object in space. There is a direct and entangled relationship between the object and the space around it. Change the object, and you automatically change the space surrounding it.
It turns out that objects, rather than just being objects, are better described as a series of relationships. You might not be able to know exactly where one particle is, but if it is entangled with another particle having an opposite position, you can know that whatever you do to one particle will always affect its entangled particle. So if one egg is sunny side up and its entangled partner is sunny side down, you can flip one egg and automatically and always flip the other too. This is called “entangled states.”
In quantum mechanics, we have to give up absolutes and accept probabilities. Perhaps that’s why we never notice quantum mechanics in our daily lives. QM says there is a real possibility that all of the atoms in your body could pass right through the atoms of a wall, allowing you to walk right though it. Does that mean Kung-Fu masters can really walk through walls? No, because on the scale of a human being, the probability of that happening is incredibly small, almost non-existent. But on the scale of the atom, it can happen. In fact it does happen, and furthermore, we rely on it happening. It’s called “quantum tunneling” and it’s the basis for our modern electronics and microchips.
Science and philosophy come together in quantum mechanics. We often say that the age of determinism in science, where A causes B through a direct line of events, has been replaced with the age of probability. Einstein hated this idea. His aversion to it shows up in his famous quote, “God does not play dice with the Universe.” Even today many people reject the underlying philosophical ramifications of QM while using its principles and products in every day life. But I find the QM idea of probabilities, relationships and entangled states to be an active and connecting philosophy. And we’ve only begun to explore it.
Until next week, my friends, enjoy the view
Tuesday, August 28, 2007
Wednesday, August 22, 2007
Dark Ages
8/26/07 – 9/1/07
by C. Zaitz
When we think of the “dark ages” in western history, especially in science, we often think of folks believing the earth was flat and that the stars were little lights attached to a crystal sphere which circled the earth. In reality, just like today, people probably didn’t spend too much time thinking about how the stars were attached to the heavens, since they were busy trying to survive on meager meals and trying to avoid diseases. But there are always a few folks with either the time, or the light headedness from lack of food, who think about the heavens. All was not dark in the dark ages.
If we can get beyond the strong terms of contrast used throughout history like black and white, light and dark, we can begin to see the time period in Europe we generally regard as the “dark ages” more realistically. Between the years 500-1000 AD, or the early Middle Ages, people didn’t stop working, they made things, they communicated, and they thought. The problem with the dark ages, historians say, is that there is very little recorded information. Without recorded events, the time period becomes “dark” to historians. Unfortunately, writers from later times have shaped the way we think about the so-called dark ages, comparing them with what came before, the glorious Roman Empire, and what came after, the High Middle Ages and the Enlightenment. However, it isn’t completely accurate to say that no advancements to civilization came during that period. By the middle ages, most people believed that the earth was a very small part of an immense universe. Folks knew the earth was round, and though the science of the sky was intricately tied to prognostication and astrology, there was a considerable bank of knowledge about the planets and stars.
But in these times, people had to deal with an ongoing scarcity of food, hardships of weather, and now it seems scientists have found evidence that crop failure and a series of very cold summers may have been caused by some catastrophic event, such as volcanic eruption or asteroid collision. The first appearance of the Bubonic Plague came around this time, and before it was done centuries later, it had killed perhaps one half or more of the entire population of Europe. No wonder they didn’t record their history.
I wonder if the folks in the sixth century would have done anything different had they known the plague would kill every other person. I wonder what they would have done to prevent it. Eerily, the same things that may have prevented folks from recording their history then are predicted to happen to humanity again. Are we prepared? There are folks who look to the skies and tell us that we should begin to colonize other planets, but most of us aren’t listening. We are just trying to get through the day with modern day plagues of disease and lack of food and shelter many people worldwide suffer from.
I hope that the visionaries who want to travel to other planets, and the rest of us who support them, will make it happen in our lifetimes. I hope we learn from our history, and that we can keep a light on in the darkness that we all sometimes face.
Until next week, my friends, enjoy the view.
by C. Zaitz
When we think of the “dark ages” in western history, especially in science, we often think of folks believing the earth was flat and that the stars were little lights attached to a crystal sphere which circled the earth. In reality, just like today, people probably didn’t spend too much time thinking about how the stars were attached to the heavens, since they were busy trying to survive on meager meals and trying to avoid diseases. But there are always a few folks with either the time, or the light headedness from lack of food, who think about the heavens. All was not dark in the dark ages.
If we can get beyond the strong terms of contrast used throughout history like black and white, light and dark, we can begin to see the time period in Europe we generally regard as the “dark ages” more realistically. Between the years 500-1000 AD, or the early Middle Ages, people didn’t stop working, they made things, they communicated, and they thought. The problem with the dark ages, historians say, is that there is very little recorded information. Without recorded events, the time period becomes “dark” to historians. Unfortunately, writers from later times have shaped the way we think about the so-called dark ages, comparing them with what came before, the glorious Roman Empire, and what came after, the High Middle Ages and the Enlightenment. However, it isn’t completely accurate to say that no advancements to civilization came during that period. By the middle ages, most people believed that the earth was a very small part of an immense universe. Folks knew the earth was round, and though the science of the sky was intricately tied to prognostication and astrology, there was a considerable bank of knowledge about the planets and stars.
But in these times, people had to deal with an ongoing scarcity of food, hardships of weather, and now it seems scientists have found evidence that crop failure and a series of very cold summers may have been caused by some catastrophic event, such as volcanic eruption or asteroid collision. The first appearance of the Bubonic Plague came around this time, and before it was done centuries later, it had killed perhaps one half or more of the entire population of Europe. No wonder they didn’t record their history.
I wonder if the folks in the sixth century would have done anything different had they known the plague would kill every other person. I wonder what they would have done to prevent it. Eerily, the same things that may have prevented folks from recording their history then are predicted to happen to humanity again. Are we prepared? There are folks who look to the skies and tell us that we should begin to colonize other planets, but most of us aren’t listening. We are just trying to get through the day with modern day plagues of disease and lack of food and shelter many people worldwide suffer from.
I hope that the visionaries who want to travel to other planets, and the rest of us who support them, will make it happen in our lifetimes. I hope we learn from our history, and that we can keep a light on in the darkness that we all sometimes face.
Until next week, my friends, enjoy the view.
Tuesday, August 21, 2007
Wednesday, August 15, 2007
Disappointment
8/19/07 – 8/26/07
by C. Zaitz
Sometimes when a person takes their first look through a telescope, they get a feeling of, “is that all there is? Where are the colors? Why is it so small and faint?” Ah, you were expecting Hubble Space Telescope photographic quality. How disappointing! Hubble Space Telescope photos are works of art, created from information traveling by radio frequencies over hundreds, thousands, and in the case of the Hubble Deep Field image, billions of light years.
The images are breathtaking. Who can forget the famous “Pillars of Creation,” the image of the Eagle Nebula whose elongated fingers of gas and dust may harbor baby star systems. Or the Deep Field, an image made by opening the Hubble’s photographic eyeball and having it stare at a tiny area of space for a very, very long time. But how do these images get back to earth? Actually, they come to us in black and white, as a series of zeroes and ones, strung along in complicated patterns like strands of DNA. Once they get to earth, computers assemble the information into black and white images. So how did they get so colorful?
Astronomers, or should I say artists, add it later. They use a computer program like Photoshop to color in the gases and clouds with tints they assign. But color is a hard thing to define. We each perceive it differently. Some people have a very keen sense of color, and some are color blind, meaning that the colors they see are different from what most of us see. My dad often confuses red and green, because, he says, red is a very dull color. Most of us don’t see it that way. In the the Pillars of Creation, both hydrogen and sulfur were detected as a red color in the clouds of gas. Astronomers changed the hydrogen to green so it could be distinguished from the sulfur. What we got was a gorgeous, colorful, if not accurate image that filled our imaginations. But what does accurate mean when it comes to color? It’s difficult to define an exact color because it is mostly perception. So how far from red can we stray before it becomes green? Or does it really matter? Dad thought they were still the same color!
How often have I said, “here’s Betelgeuse, a red star,” or, “this is Rigel, a blue star.” No wonder people get disappointed when they are expecting the star to be the color of Bozo’s nose in the sky. I could say, “Betelgeuse radiates light mostly in the infrared and red end of the spectrum, so it’s considered a “red star,” but it is so far away that the very little bit of light we get from it is only slightly tinged orangey-red.” But that’s pretty long-winded! So we oversimplify.
The Hubble pictures are so inspiring that I don’t think the colors are an issue. The only problem comes when people expect to see those kinds of images through a telescope. If you are expecting your view through a friend’s telescope to look like the poster you saw in the mall, you’ll be disappointed. But if you have patience and look with eyes and mind ready to see detail and to absorb what you are looking at, you’re bound to avoid disappointment.
Until next week, my friends, enjoy the view.
by C. Zaitz
Sometimes when a person takes their first look through a telescope, they get a feeling of, “is that all there is? Where are the colors? Why is it so small and faint?” Ah, you were expecting Hubble Space Telescope photographic quality. How disappointing! Hubble Space Telescope photos are works of art, created from information traveling by radio frequencies over hundreds, thousands, and in the case of the Hubble Deep Field image, billions of light years.
The images are breathtaking. Who can forget the famous “Pillars of Creation,” the image of the Eagle Nebula whose elongated fingers of gas and dust may harbor baby star systems. Or the Deep Field, an image made by opening the Hubble’s photographic eyeball and having it stare at a tiny area of space for a very, very long time. But how do these images get back to earth? Actually, they come to us in black and white, as a series of zeroes and ones, strung along in complicated patterns like strands of DNA. Once they get to earth, computers assemble the information into black and white images. So how did they get so colorful?
Astronomers, or should I say artists, add it later. They use a computer program like Photoshop to color in the gases and clouds with tints they assign. But color is a hard thing to define. We each perceive it differently. Some people have a very keen sense of color, and some are color blind, meaning that the colors they see are different from what most of us see. My dad often confuses red and green, because, he says, red is a very dull color. Most of us don’t see it that way. In the the Pillars of Creation, both hydrogen and sulfur were detected as a red color in the clouds of gas. Astronomers changed the hydrogen to green so it could be distinguished from the sulfur. What we got was a gorgeous, colorful, if not accurate image that filled our imaginations. But what does accurate mean when it comes to color? It’s difficult to define an exact color because it is mostly perception. So how far from red can we stray before it becomes green? Or does it really matter? Dad thought they were still the same color!
How often have I said, “here’s Betelgeuse, a red star,” or, “this is Rigel, a blue star.” No wonder people get disappointed when they are expecting the star to be the color of Bozo’s nose in the sky. I could say, “Betelgeuse radiates light mostly in the infrared and red end of the spectrum, so it’s considered a “red star,” but it is so far away that the very little bit of light we get from it is only slightly tinged orangey-red.” But that’s pretty long-winded! So we oversimplify.
The Hubble pictures are so inspiring that I don’t think the colors are an issue. The only problem comes when people expect to see those kinds of images through a telescope. If you are expecting your view through a friend’s telescope to look like the poster you saw in the mall, you’ll be disappointed. But if you have patience and look with eyes and mind ready to see detail and to absorb what you are looking at, you’re bound to avoid disappointment.
Until next week, my friends, enjoy the view.
Wednesday, August 08, 2007
It's Just a Theory...
8/12/07 – 8/18/07
by C. Zaitz
If science is based on “theories,” how do we know they are true? After all, a theory isn’t necessarily truth or law, is it?
All scientific theories begin as a hypothesis, or a possible answer to a question we ask. For the question, “Why don’t we fall off the earth if it’s round?” we could invent some pretty cool explanations. For example, we have seen how magnets on earth attract each other, and we know that iron can be magnetic. If earth is a big magnet, maybe it pulls the iron in our blood toward it. But then we remember that feathers and leaves also fall to earth and they have no iron in them. Oops, back to the drawing board with our hypothesis.
We will have to gather observations and do experiments to come up with another hypothesis. We have to design experiments that will test exactly what we want to test without introducing too much error. And we have to accept the answers we get, even if they don’t agree with our hypothesis. The key to scientific theories is that they need to be falsifiable. That means that we must be able to test to see if a hypothesis fails. If it does, we have to refine it or chuck it completely. If we make all reasonable tests and it holds up, it may become a theory.
In the late 17th century when Sir Isaac Newton began to think about what made apples fall and held the moon in orbit, he didn’t have a word for the force he was trying to describe. He wasn’t trying to prove a theory; he was trying to find a reasonable hypothesis to explain his observations. He needed a mathematical way to describe how objects move, so he developed calculus. With that tool, he was able to find an equation that worked in every case he tried. Finally he came up with a name for what he was describing, from the Latin, “gravitas,” meaning weight or heaviness. Today we call them the Laws of Gravitation, but they are really theories that have held up over time and trials. But new technology brings new tests.
By the beginning of the 20th century, Albert Einstein was able to test the laws of gravity around a massive object, the Sun, and found that the “laws” needed to be modified. By the time he was done, he had changed the way we think about gravity. No longer do we imagine it as an invisible magnet, but more like a fabric in which we are all embedded. Our movements are shaped by this fabric, which itself is shaped by mass. We follow its curves like golf balls on a putt putt course. Einstein called it spacetime, and scientists are still unraveling the implications today.
The word theory deserves more “gravity” than it is usually given. In order for a hypothesis to be scientific and to become a theory, it has to be tested. That’s why religious or “new age” ideas are often not considered to be in the realm of science. I believe it’s important for us to understand how science works. Otherwise we might never have known how gravity works, and therefore never be able to fly a rocket to the moon. Scientific theories are the only things that let us do that.
Until next week, my friends, enjoy the view.
by C. Zaitz
If science is based on “theories,” how do we know they are true? After all, a theory isn’t necessarily truth or law, is it?
All scientific theories begin as a hypothesis, or a possible answer to a question we ask. For the question, “Why don’t we fall off the earth if it’s round?” we could invent some pretty cool explanations. For example, we have seen how magnets on earth attract each other, and we know that iron can be magnetic. If earth is a big magnet, maybe it pulls the iron in our blood toward it. But then we remember that feathers and leaves also fall to earth and they have no iron in them. Oops, back to the drawing board with our hypothesis.
We will have to gather observations and do experiments to come up with another hypothesis. We have to design experiments that will test exactly what we want to test without introducing too much error. And we have to accept the answers we get, even if they don’t agree with our hypothesis. The key to scientific theories is that they need to be falsifiable. That means that we must be able to test to see if a hypothesis fails. If it does, we have to refine it or chuck it completely. If we make all reasonable tests and it holds up, it may become a theory.
In the late 17th century when Sir Isaac Newton began to think about what made apples fall and held the moon in orbit, he didn’t have a word for the force he was trying to describe. He wasn’t trying to prove a theory; he was trying to find a reasonable hypothesis to explain his observations. He needed a mathematical way to describe how objects move, so he developed calculus. With that tool, he was able to find an equation that worked in every case he tried. Finally he came up with a name for what he was describing, from the Latin, “gravitas,” meaning weight or heaviness. Today we call them the Laws of Gravitation, but they are really theories that have held up over time and trials. But new technology brings new tests.
By the beginning of the 20th century, Albert Einstein was able to test the laws of gravity around a massive object, the Sun, and found that the “laws” needed to be modified. By the time he was done, he had changed the way we think about gravity. No longer do we imagine it as an invisible magnet, but more like a fabric in which we are all embedded. Our movements are shaped by this fabric, which itself is shaped by mass. We follow its curves like golf balls on a putt putt course. Einstein called it spacetime, and scientists are still unraveling the implications today.
The word theory deserves more “gravity” than it is usually given. In order for a hypothesis to be scientific and to become a theory, it has to be tested. That’s why religious or “new age” ideas are often not considered to be in the realm of science. I believe it’s important for us to understand how science works. Otherwise we might never have known how gravity works, and therefore never be able to fly a rocket to the moon. Scientific theories are the only things that let us do that.
Until next week, my friends, enjoy the view.
Wednesday, August 01, 2007
Fiery Skies of August
8/5/07 – 8/11/07
by C. Zaitz
Every August, the earth passes through a part of its orbit where a vast cloud of debris awaits. The debris consists of tiny particles, many no larger than a mote of dust or grain of sand, left behind by a comet. As earth plows through the cloud, the tiny bits of rock are jammed into the thick atmosphere and create spectacular plasma trails as they incinerate. These are the Perseid meteors, and the nights of August 11th and 12th will be the peak this year.
I find it odd that particles so very tiny can make such a fiery fuss in the sky. So do other scientists, and it hasn’t been completely clear what is actually making the light. Scientist study the light from meteors to find out if it comes from ionized gas as the meteorite interacts with the air and melts and sublimates, or if it’s from the compressed and heated air that the meteorite creates as it slams in at over 40 miles per second. It may be both, but meteor spectra tell us that most of the light contains ionized bits of meteorite, making the first explanation more plausible as the main cause.
This year, the event of the Perseid meteor shower is predicted to be good. The moon will not be around to outshine the sometimes faint streaks of light, and if you can find a spot where the sky is not tainted by artificial lights, the chances are great for you to see several meteors a minute. Perseids can go off in any direction, but if you trace the streak back to the source, you will be somewhere near the constellation Perseus. Though the average sighting may be one per minute, often you will see a “clumping effect” where you may see 3-5 in a minute but then experience a lull.
The very best time to see them is always between midnight and sunrise, but that’s inconvenient for most of us. Luckily, anytime after twilight is fine, though if you can stay up, the view will get dramatically better towards morning. You don’t have to know where Perseus is, which is handy since he’s not the most spectacular of all constellations. Look toward the northeast in the early evening, and higher in the north more overhead as night turns to morning. All you really need is a fairly dark sky, perhaps a lawnchair, and some patience.
Meteor showers are one of the most fun things to watch in astronomy. You do not need the aid of binoculars or a telescope to enjoy a meteor shower, but you can try to photograph them if you’re a gambler or just very patient! You can stay out late with friends and count them or just try to be the first to see the biggest and brightest one of the night. It’s always fun to hear someone shout “There’s one” and have everyone sigh because by the time someone says those words, the meteor is usually gone. Meteor showers are social events, and a great way to watch the sky with your loved ones and friends. I encourage you to take your children or parents out for the evening and enjoy the natural show of the Perseid meteor shower.
Until next week, my friends, enjoy the view.
by C. Zaitz
Every August, the earth passes through a part of its orbit where a vast cloud of debris awaits. The debris consists of tiny particles, many no larger than a mote of dust or grain of sand, left behind by a comet. As earth plows through the cloud, the tiny bits of rock are jammed into the thick atmosphere and create spectacular plasma trails as they incinerate. These are the Perseid meteors, and the nights of August 11th and 12th will be the peak this year.
I find it odd that particles so very tiny can make such a fiery fuss in the sky. So do other scientists, and it hasn’t been completely clear what is actually making the light. Scientist study the light from meteors to find out if it comes from ionized gas as the meteorite interacts with the air and melts and sublimates, or if it’s from the compressed and heated air that the meteorite creates as it slams in at over 40 miles per second. It may be both, but meteor spectra tell us that most of the light contains ionized bits of meteorite, making the first explanation more plausible as the main cause.
This year, the event of the Perseid meteor shower is predicted to be good. The moon will not be around to outshine the sometimes faint streaks of light, and if you can find a spot where the sky is not tainted by artificial lights, the chances are great for you to see several meteors a minute. Perseids can go off in any direction, but if you trace the streak back to the source, you will be somewhere near the constellation Perseus. Though the average sighting may be one per minute, often you will see a “clumping effect” where you may see 3-5 in a minute but then experience a lull.
The very best time to see them is always between midnight and sunrise, but that’s inconvenient for most of us. Luckily, anytime after twilight is fine, though if you can stay up, the view will get dramatically better towards morning. You don’t have to know where Perseus is, which is handy since he’s not the most spectacular of all constellations. Look toward the northeast in the early evening, and higher in the north more overhead as night turns to morning. All you really need is a fairly dark sky, perhaps a lawnchair, and some patience.
Meteor showers are one of the most fun things to watch in astronomy. You do not need the aid of binoculars or a telescope to enjoy a meteor shower, but you can try to photograph them if you’re a gambler or just very patient! You can stay out late with friends and count them or just try to be the first to see the biggest and brightest one of the night. It’s always fun to hear someone shout “There’s one” and have everyone sigh because by the time someone says those words, the meteor is usually gone. Meteor showers are social events, and a great way to watch the sky with your loved ones and friends. I encourage you to take your children or parents out for the evening and enjoy the natural show of the Perseid meteor shower.
Until next week, my friends, enjoy the view.
Wednesday, July 25, 2007
Colonists
7/22/07 - 7/29/07
by C. Zaitz
This year marks the 400th anniversary of the first permanent English settlement in the Americas. Jamestown, Virginia is known as the birthplace of the country, where the first boatload of eager colonists landed. They arrived in May, and I can imagine that the summer was filled with building, hunting, cooking and fending off human and animal enemies. By July I imagine that the colonists were wondering what they had been thinking, coming to a new world so far from home. They must have been hot, hungry, riddled with mosquito bites and maybe a few arrow wounds. But enough of them survived the terrible famines and attacks from the Spanish and Natives to build homes, churches and official buildings, to flourish and become farmers and businessmen.
400 years later, we can wonder what happened to that colonizing spirit. When you first heard that we’d gone to the moon, didn’t you think Mars was next? What happened? Yes, space travel is very dangerous, expensive and time consuming, but was not also crossing the Atlantic to the New World?
Old colonizing risks: Running out of food and water. Disease and pestilence. Getting speared by someone already living there. Death.
New colonizing risks: Running out of food, air and water. Disease and pestilence. Getting lasered by someone already living there. Death.
So why haven’t we planned a mission to Mars? Are the risks any greater? Are the costs heavier? If we really wanted to travel to Mars, we would. America has not been frugal when its will was strong. Why do we not establish a mission to Mars, to walk the rusty sands and build a human presence on that nearby planet? Perhaps we need an outside menace to motivate us. The mission to the moon was a response to immediate threat of Soviet superiority. Without that threat, it’s not obvious that we would have endured the expense and the risk. But being motivated by threat is not the best case scenario, since the threats that would motivate us to travel to other planets usually involves the destruction of our own planet.
But it’s not all gloom and doom. Economic incentive seems to be what drives us today, rather than fear of asteroid collision, irreversible global warming, or even nuclear holocaust. Some say our governments should pool resources and offer incentives to private companies to innovate. Private companies can often get the job done with less bureaucracy, more efficiency, and less waste than governments. That requires widespread cooperation, however, and economic motivation. Companies need to know what they will gain from the endeavor. On the other hand, did the Jamestown colonists really know what they were getting into before they left England? They surely weren’t making a profit during the first years of starvation.
I don’t think our will is weak. We are fascinated by space travel, by UFOs and aliens. Maybe we are just yearning for proof that it can be done. Whatever our ultimate motivation, I hope that it includes our will to survive and our curiosity to know the universe. And I hope we don’t wait too long to get started. Who knows where we’ll be in 400 more years. I hope it doesn’t take a threat of Jupiterian superiority to get us motivated, because by then, it may be too late.
Until next week, my friends, enjoy the view.
by C. Zaitz
This year marks the 400th anniversary of the first permanent English settlement in the Americas. Jamestown, Virginia is known as the birthplace of the country, where the first boatload of eager colonists landed. They arrived in May, and I can imagine that the summer was filled with building, hunting, cooking and fending off human and animal enemies. By July I imagine that the colonists were wondering what they had been thinking, coming to a new world so far from home. They must have been hot, hungry, riddled with mosquito bites and maybe a few arrow wounds. But enough of them survived the terrible famines and attacks from the Spanish and Natives to build homes, churches and official buildings, to flourish and become farmers and businessmen.
400 years later, we can wonder what happened to that colonizing spirit. When you first heard that we’d gone to the moon, didn’t you think Mars was next? What happened? Yes, space travel is very dangerous, expensive and time consuming, but was not also crossing the Atlantic to the New World?
Old colonizing risks: Running out of food and water. Disease and pestilence. Getting speared by someone already living there. Death.
New colonizing risks: Running out of food, air and water. Disease and pestilence. Getting lasered by someone already living there. Death.
So why haven’t we planned a mission to Mars? Are the risks any greater? Are the costs heavier? If we really wanted to travel to Mars, we would. America has not been frugal when its will was strong. Why do we not establish a mission to Mars, to walk the rusty sands and build a human presence on that nearby planet? Perhaps we need an outside menace to motivate us. The mission to the moon was a response to immediate threat of Soviet superiority. Without that threat, it’s not obvious that we would have endured the expense and the risk. But being motivated by threat is not the best case scenario, since the threats that would motivate us to travel to other planets usually involves the destruction of our own planet.
But it’s not all gloom and doom. Economic incentive seems to be what drives us today, rather than fear of asteroid collision, irreversible global warming, or even nuclear holocaust. Some say our governments should pool resources and offer incentives to private companies to innovate. Private companies can often get the job done with less bureaucracy, more efficiency, and less waste than governments. That requires widespread cooperation, however, and economic motivation. Companies need to know what they will gain from the endeavor. On the other hand, did the Jamestown colonists really know what they were getting into before they left England? They surely weren’t making a profit during the first years of starvation.
I don’t think our will is weak. We are fascinated by space travel, by UFOs and aliens. Maybe we are just yearning for proof that it can be done. Whatever our ultimate motivation, I hope that it includes our will to survive and our curiosity to know the universe. And I hope we don’t wait too long to get started. Who knows where we’ll be in 400 more years. I hope it doesn’t take a threat of Jupiterian superiority to get us motivated, because by then, it may be too late.
Until next week, my friends, enjoy the view.
Tuesday, July 17, 2007
Night Watchmen
7/15/07 - 7/21/07
by C. Zaitz
There are a lot of things floating above us, circling the planet all day long, all night long. While we are all sleeping, there are flocks of satellites gliding silently overhead. If you’ve been out this summer even for ten minutes of star gazing, you’ve seen them. I love it when you can see more than one at a time. They look like a flotilla of space ships, and I imagine a future where they are just commuters coming to and from work.
Meanwhile I looked into what is really up there. Mostly, it’s derelict satellites, parts of old rockets, debris from collisions and even frozen space sewage. It seems the astronauts launch it out into space to get rid of it. Unfortunately, the bags of waste have the same orbit as they do, so it is not unheard of that someone might meet up with it in a future orbit.
There are many different types of orbits for satellites. The International Space Station and most of our weather satellites are in LEO’s, or low earth orbits. They are speeding along at nearly 20,000 mph because they are so “close” to earth, at only 200-500 miles. They circle the earth every 90 minutes. If they went any slower, earth’s gravity would overcome them and they would tumble to earth, burning streaks of incinerated satellite parts as they fell.
A common LEO, especially for satellites that need to see the whole earth over time, is a polar orbit. As the satellite travels from pole to pole, the earth rotates underneath. Over time, the satellite will have passed over the entire planet, just by maintaining its orbit. They can map the entire earth. Remote sensing and long term weather satellites are often in these polar orbits. These are very common to see. I saw three the other night, all at slightly different speeds, but traveling along the same trajectory like silent watchmen.
A GEO is a much higher orbit. GEOs are geosynchronous orbits, meaning they are up so high and going just the right speed so that they appear to be stationary over a certain spot on earth. You can imagine what use these orbits would be, especially if you were curious about a certain spot on earth. Unfortunately, at 22,000 miles up, the view is not as sharp as a lower orbiting satellite's. Their advantage is that they have a large coverage area. We use them for relaying a signal for communication or broadcasting. Our telecommunications satellites are in GEO orbits. The problem with this kind of orbit is that the satellite must be directly over the equator to maintain the orbit. That leaves out the polar regions, and those folks want their satellite TV, just like we do. So we have another orbit, a highly elliptical one, which can come close to earth at one point, even a polar region, and then wander father out.
If you’d like to know exactly when satellites are passing over your head, you can go to the Heavens Above website and enter your town. You’ll be surprised at what you can see. And it’s just the tip of the iceberg of the night watchmen. You’ll be surprised at who’s seeing you!
Until next week, my friends, enjoy the view.
by C. Zaitz
There are a lot of things floating above us, circling the planet all day long, all night long. While we are all sleeping, there are flocks of satellites gliding silently overhead. If you’ve been out this summer even for ten minutes of star gazing, you’ve seen them. I love it when you can see more than one at a time. They look like a flotilla of space ships, and I imagine a future where they are just commuters coming to and from work.
Meanwhile I looked into what is really up there. Mostly, it’s derelict satellites, parts of old rockets, debris from collisions and even frozen space sewage. It seems the astronauts launch it out into space to get rid of it. Unfortunately, the bags of waste have the same orbit as they do, so it is not unheard of that someone might meet up with it in a future orbit.
There are many different types of orbits for satellites. The International Space Station and most of our weather satellites are in LEO’s, or low earth orbits. They are speeding along at nearly 20,000 mph because they are so “close” to earth, at only 200-500 miles. They circle the earth every 90 minutes. If they went any slower, earth’s gravity would overcome them and they would tumble to earth, burning streaks of incinerated satellite parts as they fell.
A common LEO, especially for satellites that need to see the whole earth over time, is a polar orbit. As the satellite travels from pole to pole, the earth rotates underneath. Over time, the satellite will have passed over the entire planet, just by maintaining its orbit. They can map the entire earth. Remote sensing and long term weather satellites are often in these polar orbits. These are very common to see. I saw three the other night, all at slightly different speeds, but traveling along the same trajectory like silent watchmen.
A GEO is a much higher orbit. GEOs are geosynchronous orbits, meaning they are up so high and going just the right speed so that they appear to be stationary over a certain spot on earth. You can imagine what use these orbits would be, especially if you were curious about a certain spot on earth. Unfortunately, at 22,000 miles up, the view is not as sharp as a lower orbiting satellite's. Their advantage is that they have a large coverage area. We use them for relaying a signal for communication or broadcasting. Our telecommunications satellites are in GEO orbits. The problem with this kind of orbit is that the satellite must be directly over the equator to maintain the orbit. That leaves out the polar regions, and those folks want their satellite TV, just like we do. So we have another orbit, a highly elliptical one, which can come close to earth at one point, even a polar region, and then wander father out.
If you’d like to know exactly when satellites are passing over your head, you can go to the Heavens Above website and enter your town. You’ll be surprised at what you can see. And it’s just the tip of the iceberg of the night watchmen. You’ll be surprised at who’s seeing you!
Until next week, my friends, enjoy the view.
Tuesday, July 03, 2007
The Heavens
7/8/07 – 7/14/07
by C. Zaitz
I have a collection of old astronomy books. Sometimes the author will refer to the sky as “the Heavens.” What a lovely way to think of the regions above our heads. It gives the sense of the vastness and beauty of the sky, but the term does tend to lump everything together. “The Heavens” is a more encompassing term than saying the singular “heaven” but it doesn’t truly capture the layered and complex nature of what lies above.
For example, during the day, the sky is all around us, and we rarely ever look at it, just as we rarely look at the ceiling in our house. But the sky is much more interesting, even on a bland day, than the ceiling. The sky has magnificent layers of intrigue, layers of depth and color. Blue skies aren’t just blue, and grey skies are even more colorful. My favorite, of course, is the black sky of night, when all the subtle, distant and concentrated light from the stars can penetrate the atmosphere and be seen here on earth.
But sometimes when you look up, you see what looks like “heaven” from what we’ve seen in paintings and drawings. We can see rays of light coming down from the frothy, fluffy gold-edged clouds with a bright sun lighting them from behind. It’s a beautiful scene, which is probably why it was chosen to represent heaven. Those rays have a technical name. They are called crepuscular rays, which certainly isn’t as poetic a term as “heavenly rays,” but describes the rays of light that seem to spread out from behind back lit clouds, especially at twilight. Crepuscular means, “twilight,” though the effect can happen anytime there are enough particles of dust or vapor in the air to scatter light well. The cause of these rays is a combination of light and shadow. The light is always there when the sun is out, but the shadow created by an object like a cloud that gives the light a “ray” appearance.
From our perspective, the parallel rays from the sun actually look like they diverge from behind the cloud, giving them that spread out “ray from heaven” look, as if a heavenly body shone a great golden flashlight to illuminate our little patch of earth. It’s the same trick of perspective that the brain plays to make parallel railroad tracks look like they converge at a distance.
There certainly are other beautiful effects of light and shadow, scattering and perspective to be seen in the sky, but I think crepuscular rays are some of the most evocative. Perhaps it’s because they do seem to be flooding the earth with golden light, almost like a curtain opening up onto earth’s stage, as directed by something bigger than ourselves. Next time you see them, you’ll know that they are caused by natural circumstances, but you can always let those pretty rays take your gaze up into the sky. I assure you there will always be something interesting to see in “the heavens.”
Until next week, my friends, enjoy the view.
by C. Zaitz
I have a collection of old astronomy books. Sometimes the author will refer to the sky as “the Heavens.” What a lovely way to think of the regions above our heads. It gives the sense of the vastness and beauty of the sky, but the term does tend to lump everything together. “The Heavens” is a more encompassing term than saying the singular “heaven” but it doesn’t truly capture the layered and complex nature of what lies above.
For example, during the day, the sky is all around us, and we rarely ever look at it, just as we rarely look at the ceiling in our house. But the sky is much more interesting, even on a bland day, than the ceiling. The sky has magnificent layers of intrigue, layers of depth and color. Blue skies aren’t just blue, and grey skies are even more colorful. My favorite, of course, is the black sky of night, when all the subtle, distant and concentrated light from the stars can penetrate the atmosphere and be seen here on earth.
But sometimes when you look up, you see what looks like “heaven” from what we’ve seen in paintings and drawings. We can see rays of light coming down from the frothy, fluffy gold-edged clouds with a bright sun lighting them from behind. It’s a beautiful scene, which is probably why it was chosen to represent heaven. Those rays have a technical name. They are called crepuscular rays, which certainly isn’t as poetic a term as “heavenly rays,” but describes the rays of light that seem to spread out from behind back lit clouds, especially at twilight. Crepuscular means, “twilight,” though the effect can happen anytime there are enough particles of dust or vapor in the air to scatter light well. The cause of these rays is a combination of light and shadow. The light is always there when the sun is out, but the shadow created by an object like a cloud that gives the light a “ray” appearance.
From our perspective, the parallel rays from the sun actually look like they diverge from behind the cloud, giving them that spread out “ray from heaven” look, as if a heavenly body shone a great golden flashlight to illuminate our little patch of earth. It’s the same trick of perspective that the brain plays to make parallel railroad tracks look like they converge at a distance.
There certainly are other beautiful effects of light and shadow, scattering and perspective to be seen in the sky, but I think crepuscular rays are some of the most evocative. Perhaps it’s because they do seem to be flooding the earth with golden light, almost like a curtain opening up onto earth’s stage, as directed by something bigger than ourselves. Next time you see them, you’ll know that they are caused by natural circumstances, but you can always let those pretty rays take your gaze up into the sky. I assure you there will always be something interesting to see in “the heavens.”
Until next week, my friends, enjoy the view.
Wednesday, June 27, 2007
Summer Vacations
7/1/07 – 7/7/07
By C. Zaitz
‘Tis the season to get away. Whether it is vacation travel time, visiting relatives time, or maybe just taking a vacation in your mind time, most folks like to change locations in the summer. I’m often asked about how the sky changes when you travel. The answer is: it depends on where you’re going! If you are traveling mostly due east or west, you don’t have to worry. You’ll see pretty much the same sky you will “here,” at pretty much the same time of the evening, give or take some minutes depending on how close you are to the edge of your time zone. For example, if you travel to Chicago from Detroit, you’ll notice a large difference in actual sunset time. Chicago is on the eastern edge of the Central zone, and we are on the western edge of the Eastern. We gain an hour by traveling to Chicago, so though physically the two cities aren’t that far apart, Detroit has sunset around 9pm EDT, and Chicago sees it at 8:15pm CDT.
If you’re traveling north or south of “here” (wherever you are), you’ll start to see some differences. From Michigan and pretty much anywhere in the US, the solar system objects make a path across the southern sky as they seem to travel east to west. The further south you go, the higher they will be in the sky. As you travel close to the equator, they will be above your head. As you go south of the equator, you’ll notice the parade of planets across the northern sky, but they’ll still be in the same order. Currently Venus is closest to the western horizon at sunset, followed by Saturn, with Jupiter bringing up the rear furthest toward the east. They will still seem to travel east to west, so the only difference is that you’ll be looking north, rather than south to see them.
The constellations do vary with latitude, but not that much within the US. If you travel north of here, you won’t add any new constellations to your repertoire; we see all the northern ones throughout the year already. If you go significantly south, perhaps beyond Miami, you will see sights never seen from our latitude. This is the realm of the hopelessly obscure constellations. If you thought Cancer (the crab) and Monoceros (the unicorn) were hard to find, try finding Antlia (the pump) or Norma (the carpenter’s square). I may be biased, but I think most of the groovy constellations are in the northern skies. That’s no excuse to stay home this summer, though!
I think the main difference you’ll find as you travel is the view of the sky in general. There aren’t too many places left that are unpolluted by street lights, but when you travel, chances are greater that you may find a few of them. I think that the mind actually sighs when it sees the vast number of stars of the Milky Way in a velvety black summer night sky. That’s when it begins to get rid of the hassles and worries of the long cold months and begins to finally get a change of perspective. And for me, that’s when the vacation really begins!
Until next week, my friends, enjoy the view.
By C. Zaitz
‘Tis the season to get away. Whether it is vacation travel time, visiting relatives time, or maybe just taking a vacation in your mind time, most folks like to change locations in the summer. I’m often asked about how the sky changes when you travel. The answer is: it depends on where you’re going! If you are traveling mostly due east or west, you don’t have to worry. You’ll see pretty much the same sky you will “here,” at pretty much the same time of the evening, give or take some minutes depending on how close you are to the edge of your time zone. For example, if you travel to Chicago from Detroit, you’ll notice a large difference in actual sunset time. Chicago is on the eastern edge of the Central zone, and we are on the western edge of the Eastern. We gain an hour by traveling to Chicago, so though physically the two cities aren’t that far apart, Detroit has sunset around 9pm EDT, and Chicago sees it at 8:15pm CDT.
If you’re traveling north or south of “here” (wherever you are), you’ll start to see some differences. From Michigan and pretty much anywhere in the US, the solar system objects make a path across the southern sky as they seem to travel east to west. The further south you go, the higher they will be in the sky. As you travel close to the equator, they will be above your head. As you go south of the equator, you’ll notice the parade of planets across the northern sky, but they’ll still be in the same order. Currently Venus is closest to the western horizon at sunset, followed by Saturn, with Jupiter bringing up the rear furthest toward the east. They will still seem to travel east to west, so the only difference is that you’ll be looking north, rather than south to see them.
The constellations do vary with latitude, but not that much within the US. If you travel north of here, you won’t add any new constellations to your repertoire; we see all the northern ones throughout the year already. If you go significantly south, perhaps beyond Miami, you will see sights never seen from our latitude. This is the realm of the hopelessly obscure constellations. If you thought Cancer (the crab) and Monoceros (the unicorn) were hard to find, try finding Antlia (the pump) or Norma (the carpenter’s square). I may be biased, but I think most of the groovy constellations are in the northern skies. That’s no excuse to stay home this summer, though!
I think the main difference you’ll find as you travel is the view of the sky in general. There aren’t too many places left that are unpolluted by street lights, but when you travel, chances are greater that you may find a few of them. I think that the mind actually sighs when it sees the vast number of stars of the Milky Way in a velvety black summer night sky. That’s when it begins to get rid of the hassles and worries of the long cold months and begins to finally get a change of perspective. And for me, that’s when the vacation really begins!
Until next week, my friends, enjoy the view.
Wednesday, June 20, 2007
Not Just a Pretty Sky
6/24/07 – 6/30/07
C. Zaitz
I am in the habit of telling people to look in the sky to see various things like planets or the moon. Then I will invariably say “it’s so pretty, just look east, blah blah etc.” Recently I was called on to clarify my statement. “So just what do you mean by pretty? What colors? What should we expect to see?” “Um, well, uh, it’s just pretty,” was all I could say.
I know people want to know what to expect, but describing beauty in the sky is tough, since it’s in the eye of the beholder. I’m always tilting upward to check out the sky, even during the day. I find beauty in the cloud formations, in the gradation of blue to white in a daytime sky, in the windblown condensation trails left behind by high flying jets. But such visceral experiences are hard to put it into words. Words are for the explanation of what a contrail is, but when I’m just enjoying it, I fall silent. I think that’s a pretty common human experience.
Recently the crescent moon, Venus, Saturn and a bright star Regulus were in alignment in the western sky. My parents were visiting so I showed them the line of objects and extended it over to Jupiter, also along the ecliptic, or plane of the solar system as seen from earth. But rather than going into the whole explanation of what we were seeing, I just pointed to them and named them. I know that some people would rather just enjoy the view rather than knowing what they were looking at and why.
On the other hand, sometimes knowing is good. In the past, and even still today, there are folks who would rather make a leap of the imagination and say that the alignment meant something, such as an omen or a foreshadowing. It is unusual it is to have such an alignment of bright objects in the sky. Unusual because it doesn’t happen every night, or even every month, but it is to be expected from time to time, since the planets do all travel the same highway, the ecliptic. For me there’s no need to assign a special significance to it other than “it’s really pretty when it happens.”
The other night I went out on a hot, humid night to gaze at the setting moon and Venus, and they were both tinted orangey red. Immediately I thought “how beautiful, a blood red crescent moon.” It occurred to me that some people in the world might think that something was wrong, that maybe the moon had exploded or was on fire. The truth was not that exciting. It was reddish because there was a lot of water vapor in the air. That’s why it felt so humid. It is the same light extinction that happens when the sun is low along the horizon making gorgeous sunsets on humid days. Knowing it allowed me to appreciate the science and the art at the same time.
There’s definitely a time and place for just looking, but we shouldn’t forget the depth behind the beauty; there are reasons for why things are the way they are. For me, knowing the reasons adds another dimension to the view, but doesn’t make it any less “pretty.” And it helps scare away the ghosts of superstition.
Until next week, my friends, enjoy the view.
C. Zaitz
I am in the habit of telling people to look in the sky to see various things like planets or the moon. Then I will invariably say “it’s so pretty, just look east, blah blah etc.” Recently I was called on to clarify my statement. “So just what do you mean by pretty? What colors? What should we expect to see?” “Um, well, uh, it’s just pretty,” was all I could say.
I know people want to know what to expect, but describing beauty in the sky is tough, since it’s in the eye of the beholder. I’m always tilting upward to check out the sky, even during the day. I find beauty in the cloud formations, in the gradation of blue to white in a daytime sky, in the windblown condensation trails left behind by high flying jets. But such visceral experiences are hard to put it into words. Words are for the explanation of what a contrail is, but when I’m just enjoying it, I fall silent. I think that’s a pretty common human experience.
Recently the crescent moon, Venus, Saturn and a bright star Regulus were in alignment in the western sky. My parents were visiting so I showed them the line of objects and extended it over to Jupiter, also along the ecliptic, or plane of the solar system as seen from earth. But rather than going into the whole explanation of what we were seeing, I just pointed to them and named them. I know that some people would rather just enjoy the view rather than knowing what they were looking at and why.
On the other hand, sometimes knowing is good. In the past, and even still today, there are folks who would rather make a leap of the imagination and say that the alignment meant something, such as an omen or a foreshadowing. It is unusual it is to have such an alignment of bright objects in the sky. Unusual because it doesn’t happen every night, or even every month, but it is to be expected from time to time, since the planets do all travel the same highway, the ecliptic. For me there’s no need to assign a special significance to it other than “it’s really pretty when it happens.”
The other night I went out on a hot, humid night to gaze at the setting moon and Venus, and they were both tinted orangey red. Immediately I thought “how beautiful, a blood red crescent moon.” It occurred to me that some people in the world might think that something was wrong, that maybe the moon had exploded or was on fire. The truth was not that exciting. It was reddish because there was a lot of water vapor in the air. That’s why it felt so humid. It is the same light extinction that happens when the sun is low along the horizon making gorgeous sunsets on humid days. Knowing it allowed me to appreciate the science and the art at the same time.
There’s definitely a time and place for just looking, but we shouldn’t forget the depth behind the beauty; there are reasons for why things are the way they are. For me, knowing the reasons adds another dimension to the view, but doesn’t make it any less “pretty.” And it helps scare away the ghosts of superstition.
Until next week, my friends, enjoy the view.
Thursday, June 14, 2007
Close Encounters
6/17/07 – 6/23/07
by C. Zaitz
Every summer, an email floats around the internet about Mars. The email tells us that no one alive will ever see this again. It’s a once in a lifetime event. Don’t miss it. Then the email says that Mars is as close as it will be for 5,000 or maybe even 60,000 years. However, the same email comes back every year, and most of it is hype. Technically, earth and Mars were closest to each other in August of 2003, but every time earth passes Mars, we have a close encounter. Human eyes can’t discern the difference between when Mars is 35 million miles from us or 40 million miles. It would be like looking at a baseball 400 miles away. You can’t really tell if it’s 50 miles closer with the unaided eye because it’s so small compared to its distance.
Currently, Mars isn’t even a player in the night sky. But there are three planets that are. Jupiter, for one. If you’re looking for close encounters, it happens that we are closer to Jupiter this month than at other times in the year, and it is definitely showing off brightly all night long. “Closest” simply means that we are on the same side of the sun as Jupiter. Imagine a Nascar track with earth on an inside lane and Jupiter further toward the outside edge. Because we are going faster and have less space to travel, we pass Jupiter. As we pass, we are closer than we are at other times. It’s happening now, and it’s a great time to use your binoculars to see Jupiter and its largest moons. If you want a fun project with kids, you can even watch it from night to night and see how the moons move around Jupiter, just like the famous astronomer Galileo did. Use a sketch pad and draw the configuration. Kids (and adults) can actually see something changing in the sky, and you never know what will spark a life-long interest in science. Galileo’s sketches changed the way people thought, and forever put to rest the idea that the earth was the center of everything.
Saturn is also up in the evening sky, but sets an hour or two after dark. Saturn is even more astounding when you see it through a telescope. Often we are jaded by seeing full color giant images of planets and space objects from the Hubble Space Telescope. But there is something special about seeing Saturn through a small telescope. You can’t see color, and it looks tiny, but you can see the rings and even a moon. It’s nearly twice as far away as Jupiter, but it is so distinctive that you really know you’re looking at a planet, not just a bright light. I highly recommend it this summer, especially with kids.
The third bright planet up in the early evening is Venus. She’s been especially showy lately, high in the west during evening twilight, and shining more brightly than airplane headlights. Her reflective clouds send a lot of sunlight our way, and because you can see her at sunset, she’s the planet you’ll notice most. At the end of June, she’ll be close to Saturn, and this will be the prettiest close encounter of all. Just look to the west as it gets dark enough to see them, around 9:45-10 pm.
Until next week, my friends, enjoy the view.
by C. Zaitz
Every summer, an email floats around the internet about Mars. The email tells us that no one alive will ever see this again. It’s a once in a lifetime event. Don’t miss it. Then the email says that Mars is as close as it will be for 5,000 or maybe even 60,000 years. However, the same email comes back every year, and most of it is hype. Technically, earth and Mars were closest to each other in August of 2003, but every time earth passes Mars, we have a close encounter. Human eyes can’t discern the difference between when Mars is 35 million miles from us or 40 million miles. It would be like looking at a baseball 400 miles away. You can’t really tell if it’s 50 miles closer with the unaided eye because it’s so small compared to its distance.
Currently, Mars isn’t even a player in the night sky. But there are three planets that are. Jupiter, for one. If you’re looking for close encounters, it happens that we are closer to Jupiter this month than at other times in the year, and it is definitely showing off brightly all night long. “Closest” simply means that we are on the same side of the sun as Jupiter. Imagine a Nascar track with earth on an inside lane and Jupiter further toward the outside edge. Because we are going faster and have less space to travel, we pass Jupiter. As we pass, we are closer than we are at other times. It’s happening now, and it’s a great time to use your binoculars to see Jupiter and its largest moons. If you want a fun project with kids, you can even watch it from night to night and see how the moons move around Jupiter, just like the famous astronomer Galileo did. Use a sketch pad and draw the configuration. Kids (and adults) can actually see something changing in the sky, and you never know what will spark a life-long interest in science. Galileo’s sketches changed the way people thought, and forever put to rest the idea that the earth was the center of everything.
Saturn is also up in the evening sky, but sets an hour or two after dark. Saturn is even more astounding when you see it through a telescope. Often we are jaded by seeing full color giant images of planets and space objects from the Hubble Space Telescope. But there is something special about seeing Saturn through a small telescope. You can’t see color, and it looks tiny, but you can see the rings and even a moon. It’s nearly twice as far away as Jupiter, but it is so distinctive that you really know you’re looking at a planet, not just a bright light. I highly recommend it this summer, especially with kids.
The third bright planet up in the early evening is Venus. She’s been especially showy lately, high in the west during evening twilight, and shining more brightly than airplane headlights. Her reflective clouds send a lot of sunlight our way, and because you can see her at sunset, she’s the planet you’ll notice most. At the end of June, she’ll be close to Saturn, and this will be the prettiest close encounter of all. Just look to the west as it gets dark enough to see them, around 9:45-10 pm.
Until next week, my friends, enjoy the view.
Wednesday, June 06, 2007
Crowning Glory
6/10/07 - 6/16/07
I happen to have a rather large collection of jewelry. Big piles of it. Drawers of it. Most of it is costume jewelry, just shiny cut glass, but that’s the stuff I love. I’ve been collecting it since kindergarten. I remember playing with a small wooden dresser at school and opening a drawer that contained a shiny necklace. I’m pretty sure I didn’t know what rhinestones were and thought I had found the crown jewels, so I promptly plopped the thing on my head, a gesture that pronounced me princess of the kindergarten class. Silly, but my fascination with rhinestones never wore off.
It was about that time that I fell in love with the sky. Was it the sparkly nature of it that drew me? Perhaps, but what I didn’t know then but to my great pleasure learned later, is that there is a sparkly crown in the sky. It’s called Corona Borealis and it crowns the sky in late spring and summer. Corona is Latin for crown, and borealis refers to the fact it’s in the northern sky, not to be confused with Corona Australis, the much less impressive Southern Crown. The northern circlet is made of seven stars, none of which are especially bright. The brightest is called Gemma, aptly named as the shiniest gem star. It’s not directly in the center, but fairly close to it.
Corona Borealis is found high in the sky, close between Hercules and Bootes. Once you find it, you may get a little thrill of seeing princess Ariadne’s crown in the sky. She was the daughter of King Minos of Crete and Pasiphae. Thanks to her mother, Ariadne was also half-sister to the Minotaur, the half bull, half human creature that lived in the labyrinth of Crete. The labyrinth was a riotous collection of maze-like hallways, a perfect home for hiding the human-flesh eating Minotaur. Pasiphae had known he was a terrible beast even as a baby, but hadn’t the heart to kill him, so he grew to be a terrible menace. To pacify the monster, each year King Minos chose seven male and seven female Athenian youths to sacrifice to the creature. One year the son of the king of Athens, Theseus, decided to put an end to this annual gruesome slaughter. He joined the group of sacrificial victims and went to meet the Minotaur.
Meanwhile, Ariadne had caught a glimpse of the handsome Theseus and instantly fell in love with him. She decided to help him by giving him a sword and a ball of thread. The sword’s purpose was obvious, but the thread was what saved Theseus from being hopelessly lost in the labyrinth. Theseus did slay the Minotaur, and was able to rescue himself and other victims by following the thread back through the labyrinth to safety. Theseus rewarded Ariadne briefly for her help by taking her to the island of Naxos, but there he abandoned her. She managed to catch the eye of Dionysus, the god of wine, who felt sorry for her and married her. He is the one who gave her the crown now seen in the evening sky.
Now we can all enjoy having a crown above our heads. Sure, it’s made of stars, not diamonds, but as with my pretty rhinestone necklace, you can make of it what you will. And now you can think of the story of Ariadne and Theseus and join the kingdom of people who have done so since early times.
Until next week, my friends, enjoy the view.
I happen to have a rather large collection of jewelry. Big piles of it. Drawers of it. Most of it is costume jewelry, just shiny cut glass, but that’s the stuff I love. I’ve been collecting it since kindergarten. I remember playing with a small wooden dresser at school and opening a drawer that contained a shiny necklace. I’m pretty sure I didn’t know what rhinestones were and thought I had found the crown jewels, so I promptly plopped the thing on my head, a gesture that pronounced me princess of the kindergarten class. Silly, but my fascination with rhinestones never wore off.
It was about that time that I fell in love with the sky. Was it the sparkly nature of it that drew me? Perhaps, but what I didn’t know then but to my great pleasure learned later, is that there is a sparkly crown in the sky. It’s called Corona Borealis and it crowns the sky in late spring and summer. Corona is Latin for crown, and borealis refers to the fact it’s in the northern sky, not to be confused with Corona Australis, the much less impressive Southern Crown. The northern circlet is made of seven stars, none of which are especially bright. The brightest is called Gemma, aptly named as the shiniest gem star. It’s not directly in the center, but fairly close to it.
Corona Borealis is found high in the sky, close between Hercules and Bootes. Once you find it, you may get a little thrill of seeing princess Ariadne’s crown in the sky. She was the daughter of King Minos of Crete and Pasiphae. Thanks to her mother, Ariadne was also half-sister to the Minotaur, the half bull, half human creature that lived in the labyrinth of Crete. The labyrinth was a riotous collection of maze-like hallways, a perfect home for hiding the human-flesh eating Minotaur. Pasiphae had known he was a terrible beast even as a baby, but hadn’t the heart to kill him, so he grew to be a terrible menace. To pacify the monster, each year King Minos chose seven male and seven female Athenian youths to sacrifice to the creature. One year the son of the king of Athens, Theseus, decided to put an end to this annual gruesome slaughter. He joined the group of sacrificial victims and went to meet the Minotaur.
Meanwhile, Ariadne had caught a glimpse of the handsome Theseus and instantly fell in love with him. She decided to help him by giving him a sword and a ball of thread. The sword’s purpose was obvious, but the thread was what saved Theseus from being hopelessly lost in the labyrinth. Theseus did slay the Minotaur, and was able to rescue himself and other victims by following the thread back through the labyrinth to safety. Theseus rewarded Ariadne briefly for her help by taking her to the island of Naxos, but there he abandoned her. She managed to catch the eye of Dionysus, the god of wine, who felt sorry for her and married her. He is the one who gave her the crown now seen in the evening sky.
Now we can all enjoy having a crown above our heads. Sure, it’s made of stars, not diamonds, but as with my pretty rhinestone necklace, you can make of it what you will. And now you can think of the story of Ariadne and Theseus and join the kingdom of people who have done so since early times.
Until next week, my friends, enjoy the view.
Tuesday, May 29, 2007
Messier Sky
6/3/07 – 6/9/07
by C. Zaitz
It is my opinion that summertime is the very best time for evening sky watching, whether you are a casual looker, an interested observer or a hard-core “Messier object” junkie. I’ve been all three at various times, but summer is the time when we can spend more quality time outside at night, gazing upward, finding your “fix” in the stars. Beyond knowing the constellations, if you really want to get to know the universe, finding Messier objects is a good way to do it. (Messier doesn’t refer to the chaos of the sky, it’s the last name of French astronomer Charles Messi “ay.”)
Monsieur Messier was an observational astronomer at the end of the 18th century who was very interested in finding new comets. This was a popular past time for an astronomer seeking to be immortalized by getting a comet named after him. However, Messier was annoyed with the countless fuzzy clouds in space that were easily confused with fuzzy comets. Messier catalogued over 100 “nebulae,” which were thought to be some sort of cloud within the galaxy. He hoped to save himself and other comet hunters the confusion of wondering if the faint fuzzy was indeed a fame-inducing object, or merely another “cloud.”
The existence of other galaxies beyond the Milky Way was not known until William Herschel and others continued cataloguing the fuzzy objects. The Herschel General Catalogue of Nebulae, listing over 5,000 objects, gave way to the New General Catalogue (NGC) in 1888, which contained nearly 8,000. Soon their true nature became clear- these clouds were not of the Milky Way at all, but each a separate “island universe” like our own. And Messier’s catalogue of galaxies, nebulae and supernovae remnants gave him more fame than any comet would have. Amateur astronomers world-over know of Messier and his wonderful catalogue of deep space objects. The NGC does not immortalize its author, but contains Messier objects as well as many more interesting destinations for the observer with time and telescope on hand.
The summer skies hold many Messier objects, known by their “M” number. Many of them have very pretty nicknames. For example, M57 is the Ring Nebula, M101 is the Pinwheel Galaxy and M104 is the Sombrero Galaxy. Other nick names are not so lovely; such as the Blackeye galaxy (M64), the Crab Nebula (M1), and the Dumbbell Nebula (M27). Cute name or not, one of the most beautiful sights to see in the late spring and summer is M13, the lovely globular cluster of stars in Hercules. A globular cluster is a tightly packed group of older stars. In M13 there are estimated to be over a million stars in a sphere of space about 100 light years across. You can see the Hercules cluster with binoculars, but it truly is best seen through a telescope.
M57, the Ring Nebula in Lyra is also a pretty sight in a telescope. It is the first planetary nebula ever discovered. It looks like an ethereal smoke ring in the black sky, but it is the outer shells of a dying star, suffering the same fate as will our sun, in some 5 billion years.
There are many more such objects within view of a typical amateur telescope, and summer amateur group star parties are the best way to see these sights, and to get to know those folks who can help you discover the universe of Messier deep space objects.
Until next week, my friends, enjoy the view.
by C. Zaitz
It is my opinion that summertime is the very best time for evening sky watching, whether you are a casual looker, an interested observer or a hard-core “Messier object” junkie. I’ve been all three at various times, but summer is the time when we can spend more quality time outside at night, gazing upward, finding your “fix” in the stars. Beyond knowing the constellations, if you really want to get to know the universe, finding Messier objects is a good way to do it. (Messier doesn’t refer to the chaos of the sky, it’s the last name of French astronomer Charles Messi “ay.”)
Monsieur Messier was an observational astronomer at the end of the 18th century who was very interested in finding new comets. This was a popular past time for an astronomer seeking to be immortalized by getting a comet named after him. However, Messier was annoyed with the countless fuzzy clouds in space that were easily confused with fuzzy comets. Messier catalogued over 100 “nebulae,” which were thought to be some sort of cloud within the galaxy. He hoped to save himself and other comet hunters the confusion of wondering if the faint fuzzy was indeed a fame-inducing object, or merely another “cloud.”
The existence of other galaxies beyond the Milky Way was not known until William Herschel and others continued cataloguing the fuzzy objects. The Herschel General Catalogue of Nebulae, listing over 5,000 objects, gave way to the New General Catalogue (NGC) in 1888, which contained nearly 8,000. Soon their true nature became clear- these clouds were not of the Milky Way at all, but each a separate “island universe” like our own. And Messier’s catalogue of galaxies, nebulae and supernovae remnants gave him more fame than any comet would have. Amateur astronomers world-over know of Messier and his wonderful catalogue of deep space objects. The NGC does not immortalize its author, but contains Messier objects as well as many more interesting destinations for the observer with time and telescope on hand.
The summer skies hold many Messier objects, known by their “M” number. Many of them have very pretty nicknames. For example, M57 is the Ring Nebula, M101 is the Pinwheel Galaxy and M104 is the Sombrero Galaxy. Other nick names are not so lovely; such as the Blackeye galaxy (M64), the Crab Nebula (M1), and the Dumbbell Nebula (M27). Cute name or not, one of the most beautiful sights to see in the late spring and summer is M13, the lovely globular cluster of stars in Hercules. A globular cluster is a tightly packed group of older stars. In M13 there are estimated to be over a million stars in a sphere of space about 100 light years across. You can see the Hercules cluster with binoculars, but it truly is best seen through a telescope.
M57, the Ring Nebula in Lyra is also a pretty sight in a telescope. It is the first planetary nebula ever discovered. It looks like an ethereal smoke ring in the black sky, but it is the outer shells of a dying star, suffering the same fate as will our sun, in some 5 billion years.
There are many more such objects within view of a typical amateur telescope, and summer amateur group star parties are the best way to see these sights, and to get to know those folks who can help you discover the universe of Messier deep space objects.
Until next week, my friends, enjoy the view.
Wednesday, May 23, 2007
Magnetism
5/27/07 – 6/2/07
by C. Zaitz
The earth is cooling. It had to. When it formed some 4.6 billion years ago, it was way too hot for any life to form. In fact, it’s taken a lot of time to cool enough for rhinos and beavers and gazelles to be able to roam freely without burning their hooves and paws and giant feet. Much of earth’s history has been spent cooling and changing into the planet we know and love. Unfortunately, earth doesn’t know and love us. It keeps changing, whether or not the life forms occupying its surface can survive it or not. It cares not whether its atmosphere grows thick or thin, whether its waters are pure, or if its movements will disrupt the parasites on its edge.
We know that huge volcanic eruptions and earthquakes can cause widespread destruction. They are caused by the movement of the plates of crust and mantle. Deeper within the earth lies the mechanism for creating an invisible shield, a barrier against the killing radiation from the sun. The earth has a fairly strong magnetic field, created and maintained by the movements of its liquid metallic outer core. The field extends out into space like a giant protective web. We have learned about the nature of our magnetic field from looking at the bottom of the ocean at the mid-Atlantic ridge. As magma flows out from the crack between two separating tectonic plates, little bits of magnetic material align in the direction of earth’s magnetic field. It hardens and the magnetic record is solidified. We can read the ocean floor like a book, and it’s telling us that over time the magnetic field of the earth changes. Sometimes it is aligned as it is now, but other times it’s completely switched. The north magnetic pole is sometimes in the southern hemisphere! What’s nerve-wracking is that while it’s switching, it can weaken and be non-existent for awhile. Our mid-Atlantic story book is telling us that it may be time for another switch. Or even more harrowing, as the earth cools and the outer core solidifies, the magnetic field may disappear forever.
Though we don’t often notice the effects of the magnetic field in our daily lives, it does provide an invisible barrier from the harsher radiation from the sun. We’re all familiar with the northern lights, which are caused by high energy solar radiation interacting with our atmosphere, spiraling in along the magnetic field lines near the poles. But what we’re not aware of is the daily bombardment of high energy particles from the sun that are deflected away from us. Without our magnetic field, we would be exposed to much more radiation than we’re used to, and it could be very harmful to all life forms on earth.
Between earth’s mantle and the cold, stark emptiness of outer space, lie the layers of geology that hold our history. Creatures have come and gone in the 3 billion year history of life on earth. It started with single celled organisms and has proliferated in the multifarious beings of today. But the creatures that were around 100 million years ago are not necessarily the ones we see now. Life has changed, often in big sweeping changes caused by the earth itself. Our magnetic field may be an important part of the plot of how life on earth changes, and we may be in store for the next chapter in the book. I hope it has a happy ending!
Until next week, my friends, enjoy the view.
by C. Zaitz
The earth is cooling. It had to. When it formed some 4.6 billion years ago, it was way too hot for any life to form. In fact, it’s taken a lot of time to cool enough for rhinos and beavers and gazelles to be able to roam freely without burning their hooves and paws and giant feet. Much of earth’s history has been spent cooling and changing into the planet we know and love. Unfortunately, earth doesn’t know and love us. It keeps changing, whether or not the life forms occupying its surface can survive it or not. It cares not whether its atmosphere grows thick or thin, whether its waters are pure, or if its movements will disrupt the parasites on its edge.
We know that huge volcanic eruptions and earthquakes can cause widespread destruction. They are caused by the movement of the plates of crust and mantle. Deeper within the earth lies the mechanism for creating an invisible shield, a barrier against the killing radiation from the sun. The earth has a fairly strong magnetic field, created and maintained by the movements of its liquid metallic outer core. The field extends out into space like a giant protective web. We have learned about the nature of our magnetic field from looking at the bottom of the ocean at the mid-Atlantic ridge. As magma flows out from the crack between two separating tectonic plates, little bits of magnetic material align in the direction of earth’s magnetic field. It hardens and the magnetic record is solidified. We can read the ocean floor like a book, and it’s telling us that over time the magnetic field of the earth changes. Sometimes it is aligned as it is now, but other times it’s completely switched. The north magnetic pole is sometimes in the southern hemisphere! What’s nerve-wracking is that while it’s switching, it can weaken and be non-existent for awhile. Our mid-Atlantic story book is telling us that it may be time for another switch. Or even more harrowing, as the earth cools and the outer core solidifies, the magnetic field may disappear forever.
Though we don’t often notice the effects of the magnetic field in our daily lives, it does provide an invisible barrier from the harsher radiation from the sun. We’re all familiar with the northern lights, which are caused by high energy solar radiation interacting with our atmosphere, spiraling in along the magnetic field lines near the poles. But what we’re not aware of is the daily bombardment of high energy particles from the sun that are deflected away from us. Without our magnetic field, we would be exposed to much more radiation than we’re used to, and it could be very harmful to all life forms on earth.
Between earth’s mantle and the cold, stark emptiness of outer space, lie the layers of geology that hold our history. Creatures have come and gone in the 3 billion year history of life on earth. It started with single celled organisms and has proliferated in the multifarious beings of today. But the creatures that were around 100 million years ago are not necessarily the ones we see now. Life has changed, often in big sweeping changes caused by the earth itself. Our magnetic field may be an important part of the plot of how life on earth changes, and we may be in store for the next chapter in the book. I hope it has a happy ending!
Until next week, my friends, enjoy the view.
Tuesday, May 15, 2007
The Short and the Long
5/21/07 – 5/27/07
by C. Zaitz
I just had one of those milestone birthdays- you know, the ones that are supposed to be more special than the rest because the number is getting so high that you have to celebrate just being alive. It made me think of the age of things. Biologically, things happen on a pretty short time scale. 70-80 years is not that long when you take into consideration how long rocks live. In astronomy we talk about ages of stars, in geology we talk about the ages of rocks and planets. In human lifescales, those numbers are incomprehensible. We have no feeling for how long it takes a rock to form, much less a star. It seems like eternity to wait for your tomatoes to ripen or for your hair to grow out after a bad cut!
Though humans have a relatively short lifespan, we are still around long enough to watch things grow and develop, die and transform. Plants and animals live in our time scale, though we marvel at the 2,000 year old sequoias and ancient cedars. But things we think of as everlasting, like rocks or stars, are not eternal. All rocks move through a cycle, from being sand sediments on the surface, to being metamorphised as the pressure of layers upon layers of rock change its character, to suffering the igneous fate of melted rocks, turning into magma and reforming on the surface as lava basalt, only to be worn away again as sand and sediment. Eons pass and the dirt just keeps changing form, nothing destroyed or created, but morphing from one form to another.
The same thing happens with stars. Our sun was once diffuse gas and dust, our own planet not more than a breath of cosmic debris, sprinkled with rare elements fused in the death throes of an ancestor star. Gravity and pressure brought everything around, and our solar system will go for at least as long as it already has, some 4.5 billion years. Then it will die, only to form something new in the next “billenia.” Will it be something completely different? A double star or part of a new open cluster of stars? Or maybe a familiar life-harboring solar system?
We happen to be living in a very particular time when we as a species can begin to understand all the cycles of life and death around us. How unique and incredible for us. It’s not surprising we’re so curious about the universe, since we see our own selves reflected in the life cycles, in the growing and dying of everything around us. I think we study these cycles to try to understand what happens when we, too, die. Will we be born again in some “next cycle?”
From an old southern banjo tune:
Little birdie, little birdie,
come sing to me your song.
I've a short while to be here,
and a long time to be gone.
Little birdie, little birdie,
What makes you fly so high?
It’s because I am a true little bird
and I do not fare to die.
I guess I like to think that nothing really goes away. We all get older and will all die, but even black holes give up their dead eventually. Nothing seems to be destroyed, and it all comes back around again, sometimes in the near future, like perennial flowers, and sometimes in the long run, like planets with life.
Until next week, my friends, enjoy the view.
by C. Zaitz
I just had one of those milestone birthdays- you know, the ones that are supposed to be more special than the rest because the number is getting so high that you have to celebrate just being alive. It made me think of the age of things. Biologically, things happen on a pretty short time scale. 70-80 years is not that long when you take into consideration how long rocks live. In astronomy we talk about ages of stars, in geology we talk about the ages of rocks and planets. In human lifescales, those numbers are incomprehensible. We have no feeling for how long it takes a rock to form, much less a star. It seems like eternity to wait for your tomatoes to ripen or for your hair to grow out after a bad cut!
Though humans have a relatively short lifespan, we are still around long enough to watch things grow and develop, die and transform. Plants and animals live in our time scale, though we marvel at the 2,000 year old sequoias and ancient cedars. But things we think of as everlasting, like rocks or stars, are not eternal. All rocks move through a cycle, from being sand sediments on the surface, to being metamorphised as the pressure of layers upon layers of rock change its character, to suffering the igneous fate of melted rocks, turning into magma and reforming on the surface as lava basalt, only to be worn away again as sand and sediment. Eons pass and the dirt just keeps changing form, nothing destroyed or created, but morphing from one form to another.
The same thing happens with stars. Our sun was once diffuse gas and dust, our own planet not more than a breath of cosmic debris, sprinkled with rare elements fused in the death throes of an ancestor star. Gravity and pressure brought everything around, and our solar system will go for at least as long as it already has, some 4.5 billion years. Then it will die, only to form something new in the next “billenia.” Will it be something completely different? A double star or part of a new open cluster of stars? Or maybe a familiar life-harboring solar system?
We happen to be living in a very particular time when we as a species can begin to understand all the cycles of life and death around us. How unique and incredible for us. It’s not surprising we’re so curious about the universe, since we see our own selves reflected in the life cycles, in the growing and dying of everything around us. I think we study these cycles to try to understand what happens when we, too, die. Will we be born again in some “next cycle?”
From an old southern banjo tune:
Little birdie, little birdie,
come sing to me your song.
I've a short while to be here,
and a long time to be gone.
Little birdie, little birdie,
What makes you fly so high?
It’s because I am a true little bird
and I do not fare to die.
I guess I like to think that nothing really goes away. We all get older and will all die, but even black holes give up their dead eventually. Nothing seems to be destroyed, and it all comes back around again, sometimes in the near future, like perennial flowers, and sometimes in the long run, like planets with life.
Until next week, my friends, enjoy the view.
Wednesday, May 09, 2007
A Weighty Subject
5/13/07 – 5/20/07
by C. Zaitz
My husband recently lost about 35 pounds due to having a very overactive thyroid gland. After an intense potion of radiation, it calmed down, so we started going back to the gym for workouts. He picked up a 35 pound weight and gave it to me to feel how much weight he’d lost. It seemed very heavy, but he carried it around for years. I started to think about weight and how we measure it, and how hard it is to lose it.
Weight is a combination of how much gravity pulls down on us, and how much “us” there is. Often in everyday life we confuse “mass” and “weight.” Mass is an intrinsic property of something, measured in pounds or kilograms. It’s how much “stuff” there is. If our mass was 150 kg on earth, it would still be 150 kg on the moon. But we wouldn’t weigh as much there, because the moon has much less gravity than earth. To get our weight, we would have to multiply our mass by how much gravity our “ground” has. Since we all live on earth and have nearly the same amount of gravity tugging on us, we forget the fact that weight and mass are different things.
Interestingly, if there were no floor or surface to stand on, you wouldn’t feel weight at all. If the floor wasn’t “pushing” back on you as hard as gravity is pulling you toward the center of the earth, you would just fall in, feeling no weight at all. This is “free fall” or “weightlessness.” It’s hard to do on earth, but the astronauts in orbit are very familiar with it. The astronauts and the space station might not have any “weight” in orbit, but they certainly have mass, which takes energy to move. That’s why it takes a lot of fuel to move stuff around even in “weightlessness.”
The fun comes when we figure out how much we’d weigh on other planets. Which would you choose, big planet or small? A 150 pound person would weigh 57 pounds on Mars. On the moon, you’d weigh a mere 25 pounds. But things get weird when you go to one of the giant, gassy planets. You’d think a mammoth planet like Saturn, a planet that could engulf earth 760 times, would have an enormous amount gravity. It does, but the farther you get from the center, the force of gravity lessens exponentially. Saturn has about 95 times more mass than earth, but its radius is 9.4 times that of earth. The math works out that on the “surface” or visible gassy outer atmosphere of Saturn, you would weigh approximately what you do on earth. The same is true of Neptune and Uranus. Jupiter is the most massive planet, 318 times more than earth, but its radius is over 11 times earth’s. Its surface gravity turns out to be about 2.5 times that of earth’s. Our 150 pound person would only weigh 375 pounds on Jupiter. Not bad for the biggest planet of them all. On Saturn, this same person would weigh a svelte 137 pounds. So you can actually “lose” weight by going to Saturn. Not to mention the weight you’d lose by eating freeze-dried peas for the three years it would take to get there.
If you’d like to check your own weight on the planets, you can go to: http://www.exploratorium.edu/ronh/weight/index.html to plan your weight loss/gain itinerary.
Until next week, my friends, enjoy the view.
by C. Zaitz
My husband recently lost about 35 pounds due to having a very overactive thyroid gland. After an intense potion of radiation, it calmed down, so we started going back to the gym for workouts. He picked up a 35 pound weight and gave it to me to feel how much weight he’d lost. It seemed very heavy, but he carried it around for years. I started to think about weight and how we measure it, and how hard it is to lose it.
Weight is a combination of how much gravity pulls down on us, and how much “us” there is. Often in everyday life we confuse “mass” and “weight.” Mass is an intrinsic property of something, measured in pounds or kilograms. It’s how much “stuff” there is. If our mass was 150 kg on earth, it would still be 150 kg on the moon. But we wouldn’t weigh as much there, because the moon has much less gravity than earth. To get our weight, we would have to multiply our mass by how much gravity our “ground” has. Since we all live on earth and have nearly the same amount of gravity tugging on us, we forget the fact that weight and mass are different things.
Interestingly, if there were no floor or surface to stand on, you wouldn’t feel weight at all. If the floor wasn’t “pushing” back on you as hard as gravity is pulling you toward the center of the earth, you would just fall in, feeling no weight at all. This is “free fall” or “weightlessness.” It’s hard to do on earth, but the astronauts in orbit are very familiar with it. The astronauts and the space station might not have any “weight” in orbit, but they certainly have mass, which takes energy to move. That’s why it takes a lot of fuel to move stuff around even in “weightlessness.”
The fun comes when we figure out how much we’d weigh on other planets. Which would you choose, big planet or small? A 150 pound person would weigh 57 pounds on Mars. On the moon, you’d weigh a mere 25 pounds. But things get weird when you go to one of the giant, gassy planets. You’d think a mammoth planet like Saturn, a planet that could engulf earth 760 times, would have an enormous amount gravity. It does, but the farther you get from the center, the force of gravity lessens exponentially. Saturn has about 95 times more mass than earth, but its radius is 9.4 times that of earth. The math works out that on the “surface” or visible gassy outer atmosphere of Saturn, you would weigh approximately what you do on earth. The same is true of Neptune and Uranus. Jupiter is the most massive planet, 318 times more than earth, but its radius is over 11 times earth’s. Its surface gravity turns out to be about 2.5 times that of earth’s. Our 150 pound person would only weigh 375 pounds on Jupiter. Not bad for the biggest planet of them all. On Saturn, this same person would weigh a svelte 137 pounds. So you can actually “lose” weight by going to Saturn. Not to mention the weight you’d lose by eating freeze-dried peas for the three years it would take to get there.
If you’d like to check your own weight on the planets, you can go to: http://www.exploratorium.edu/ronh/weight/index.html to plan your weight loss/gain itinerary.
Until next week, my friends, enjoy the view.
Wednesday, May 02, 2007
Saturn in Leo
5/6/07 – 5/12/07
by C. Zaitz
Sometimes I take comfort in the thought that, as crazy as life gets here on earth, the planets are making their planetary journeys ‘round the sun in their own time. Each planet has its own pace, and the slowest, calmest naked-eye planet is Saturn. Right now Saturn is passing in front of the constellation Leo. Some folks say that this fact can be life altering.
For fun I looked up what astrologers have to say about the planet Saturn being “in” Leo. Because Saturn orbits so slowly, it spends more than two years in any one of the zodiac constellations. Saturn was the god of change, of destroying the old to make way for the new, so astrologers say. In his modern personification, he’s a teacher, and his tests are often difficult and life changing.
Astrologically, people born when the sun was “in” Leo tend to be leaders, and very involved with ego. So to have such a “destructive” planet in Leo seems to spell disaster for the top cats. But astrologers also say that if you are willing, Saturn’s life-changing presence can open up new doors and clean your inner house. That’s a lot of deep advice from the distant gas planet and the even more distant, boiling hot gas stars that make up the constellation of Leo. Recently I showed Leo to some 4th graders. They said that Leo looks like a smiley face or a pony or a balloon. This is not a very distinguished description of Leo, but nevertheless, kind of true. In general, constellations like Hercules or Sagittarius look nothing like a giant hero or a centaur. So to assign such lofty characteristics to a group of stars scattered through space is amusing to me. Of course, it’s crafty humans that come up with the characteristics, the shapes and the connections. And it’s searching humans that read their horoscopes and make connections with their own lives. It’s kind of interesting that not only do planets reflect sunlight back to us, but they reflect our own hopes and dreams, problems and possible solutions, back to us from afar.
As far as Saturn being “in” a constellation, right now is about 8 times the distance from the earth to the sun. It takes light about and hour and half to reach us from Saturn. Stars are much farther away. The brightest star in Leo, Regulus, is nearly 80 light years away from us. The planet actually moves “in front of” the stars of the constellation as it orbits, but it sounds more mysterious and inviting to say Saturn is “in” Leo, especially if you call that part of the sky a “house.”
If you want to see Saturn in Leo, look toward the south after sunset, about halfway up the sky, and look for the “sickle” or the backwards question mark shape of stars. That is the front part of Leo, if we imagine the round sickle blade as his head and golden mane. Saturn will be just to the right or west of the sickle. This spring, Saturn’s rings are prettily displayed for anyone with a telescope. Whether or not Saturn brings life altering events for you, you can still let the beauty of the reflected light dazzle your eyes and your mind. And that can be life altering as well, especially if it moves you to use the credit card to buy a new telescope!
Until next week, my friends, enjoy the view.
by C. Zaitz
Sometimes I take comfort in the thought that, as crazy as life gets here on earth, the planets are making their planetary journeys ‘round the sun in their own time. Each planet has its own pace, and the slowest, calmest naked-eye planet is Saturn. Right now Saturn is passing in front of the constellation Leo. Some folks say that this fact can be life altering.
For fun I looked up what astrologers have to say about the planet Saturn being “in” Leo. Because Saturn orbits so slowly, it spends more than two years in any one of the zodiac constellations. Saturn was the god of change, of destroying the old to make way for the new, so astrologers say. In his modern personification, he’s a teacher, and his tests are often difficult and life changing.
Astrologically, people born when the sun was “in” Leo tend to be leaders, and very involved with ego. So to have such a “destructive” planet in Leo seems to spell disaster for the top cats. But astrologers also say that if you are willing, Saturn’s life-changing presence can open up new doors and clean your inner house. That’s a lot of deep advice from the distant gas planet and the even more distant, boiling hot gas stars that make up the constellation of Leo. Recently I showed Leo to some 4th graders. They said that Leo looks like a smiley face or a pony or a balloon. This is not a very distinguished description of Leo, but nevertheless, kind of true. In general, constellations like Hercules or Sagittarius look nothing like a giant hero or a centaur. So to assign such lofty characteristics to a group of stars scattered through space is amusing to me. Of course, it’s crafty humans that come up with the characteristics, the shapes and the connections. And it’s searching humans that read their horoscopes and make connections with their own lives. It’s kind of interesting that not only do planets reflect sunlight back to us, but they reflect our own hopes and dreams, problems and possible solutions, back to us from afar.
As far as Saturn being “in” a constellation, right now is about 8 times the distance from the earth to the sun. It takes light about and hour and half to reach us from Saturn. Stars are much farther away. The brightest star in Leo, Regulus, is nearly 80 light years away from us. The planet actually moves “in front of” the stars of the constellation as it orbits, but it sounds more mysterious and inviting to say Saturn is “in” Leo, especially if you call that part of the sky a “house.”
If you want to see Saturn in Leo, look toward the south after sunset, about halfway up the sky, and look for the “sickle” or the backwards question mark shape of stars. That is the front part of Leo, if we imagine the round sickle blade as his head and golden mane. Saturn will be just to the right or west of the sickle. This spring, Saturn’s rings are prettily displayed for anyone with a telescope. Whether or not Saturn brings life altering events for you, you can still let the beauty of the reflected light dazzle your eyes and your mind. And that can be life altering as well, especially if it moves you to use the credit card to buy a new telescope!
Until next week, my friends, enjoy the view.
Wednesday, April 25, 2007
Goldilocks Planets
4/29/07 – 5/5/07
by C. Zaitz
The news is that astronomers have found a new planet orbiting a distant star. Astronomers have been finding planets in distant solar systems for decades, but usually the planets they discover are huge, more like Jupiter on steroids than anything earth-like. With better telescopes and more research, we are beginning to see the smaller planets. One in particular is being heralded as a “Goldilocks” planet, not too big, not too small, nor too cold, nor too hot. A “just right” planet that could possibly harbor liquid water, pretty sunsets, or even life. At least that’s the theory.
Sometimes we refer to our neighboring planets as having the “Goldilocks syndrome.” Mars and Venus are our cosmic neighbors, and together, we three planets all orbit within a distance from the sun called the “habitable zone,” where the amount of solar radiation reaching the surface is conducive for reasonable temperatures. So why did earth alone develop life, so prolifically and thoroughly that not even cataclysmic events could completely wipe it out? And what went wrong with our neighbors?
Venus is a study in what can go wrong with a nice planet. Venus and earth have plenty in common. They are very close in size, composition and their distance from the sun. However, Venus ended up with a very big problem: a runaway greenhouse effect. The effect of atmosphere trapping solar radiation and making a planet warmer than it should be is common- earth and Mars also have it. However, perhaps because it gets more solar radiation or because it had more carbon dioxide in its atmosphere, Venus is in a vicious cycle where its thick clouds trap nearly all the sunlight coming in. It simply cannot cool itself off. As we raise the level of certain gasses in our own atmosphere, we run the risk of having our greenhouse effect go astray. The current warming trend of our planet is a giant red flag that we are indeed starting a process that we would not be able to stop, much less reverse.
Mars, due to its further distance from the sun or its diminutive size, has too little atmosphere, and thus too little greenhouse effect. It is too cold on the surface of Mars for water to exist in liquid form, so it ended up a dry, cold desert-like planet. We know that Mars once was warmer and are convinced that water used to flow, but unless the conditions are just right, a planet goes awry and climate changes ensue.
The newly discovered Goldilocks planet is orbiting a red dwarf star called Gliese 581, about 20 light years away. The planet is heavier than earth, with a rocky surface and most likely liquid water. That’s a lot of information about this planet, since the data they gathered is mostly about how Gliese 581 wobbles. From this wobble, astronomers can glean information about what is going around the star to make it wobble. They infer size, distance, and even composition from the wobble. They have surmised that Gliese’s planet may be very much like earth, perhaps a “just right” place where water and life could exist. However, as we look at our neighboring planets, we see a lot of variation in a planet’s fate. It will be interesting to learn more about these extra-solar planets. Even if we don’t find life, perhaps we will find answers to how planets behave, giving us insight to our own problems and possible solutions.
Until next week, my friends, enjoy the view.
by C. Zaitz
The news is that astronomers have found a new planet orbiting a distant star. Astronomers have been finding planets in distant solar systems for decades, but usually the planets they discover are huge, more like Jupiter on steroids than anything earth-like. With better telescopes and more research, we are beginning to see the smaller planets. One in particular is being heralded as a “Goldilocks” planet, not too big, not too small, nor too cold, nor too hot. A “just right” planet that could possibly harbor liquid water, pretty sunsets, or even life. At least that’s the theory.
Sometimes we refer to our neighboring planets as having the “Goldilocks syndrome.” Mars and Venus are our cosmic neighbors, and together, we three planets all orbit within a distance from the sun called the “habitable zone,” where the amount of solar radiation reaching the surface is conducive for reasonable temperatures. So why did earth alone develop life, so prolifically and thoroughly that not even cataclysmic events could completely wipe it out? And what went wrong with our neighbors?
Venus is a study in what can go wrong with a nice planet. Venus and earth have plenty in common. They are very close in size, composition and their distance from the sun. However, Venus ended up with a very big problem: a runaway greenhouse effect. The effect of atmosphere trapping solar radiation and making a planet warmer than it should be is common- earth and Mars also have it. However, perhaps because it gets more solar radiation or because it had more carbon dioxide in its atmosphere, Venus is in a vicious cycle where its thick clouds trap nearly all the sunlight coming in. It simply cannot cool itself off. As we raise the level of certain gasses in our own atmosphere, we run the risk of having our greenhouse effect go astray. The current warming trend of our planet is a giant red flag that we are indeed starting a process that we would not be able to stop, much less reverse.
Mars, due to its further distance from the sun or its diminutive size, has too little atmosphere, and thus too little greenhouse effect. It is too cold on the surface of Mars for water to exist in liquid form, so it ended up a dry, cold desert-like planet. We know that Mars once was warmer and are convinced that water used to flow, but unless the conditions are just right, a planet goes awry and climate changes ensue.
The newly discovered Goldilocks planet is orbiting a red dwarf star called Gliese 581, about 20 light years away. The planet is heavier than earth, with a rocky surface and most likely liquid water. That’s a lot of information about this planet, since the data they gathered is mostly about how Gliese 581 wobbles. From this wobble, astronomers can glean information about what is going around the star to make it wobble. They infer size, distance, and even composition from the wobble. They have surmised that Gliese’s planet may be very much like earth, perhaps a “just right” place where water and life could exist. However, as we look at our neighboring planets, we see a lot of variation in a planet’s fate. It will be interesting to learn more about these extra-solar planets. Even if we don’t find life, perhaps we will find answers to how planets behave, giving us insight to our own problems and possible solutions.
Until next week, my friends, enjoy the view.
Tuesday, April 24, 2007
Super Massive Black Holes
4/22/07 – 4/28/07
by C. Zaitz
One of the more eyebrow-raising bits of gossip heard in astronomy circles is that most galaxies, even our own, contain a super massive black hole at their cores. A super massive black hole is much heavier than a garden variety stellar black hole, which can weigh as little as one and a half suns or as much as 14 suns. That may not sound spectacular, but a black hole with the mass of 10 suns could fit into the city of Detroit. The mass of a black hole is directly related to its size, so the heavier it is, the bigger it is. But how massive is super massive?
The monster black holes we find in the centers of galaxies tend to range in mass from a hundred thousands suns to tens of billions of suns. Some scientists suggest that they started out the same way stellar-sized holes do, but over long periods of time grew larger and larger from consuming the available material in the center of the galaxy. It seems more likely that these black holes, like the one in the middle of our galaxy, formed from a large cloud of collapsing gas, creating a massive central star, some hundreds of thousands of solar masses, which then collapsed (with no supernova) to form a gigantic black hole. Since that time it has been eating everything close enough to be drawn in. Don’t worry, though; we are very, very far from the center of our galaxy, and not in the least affected by it.
We noted that the mass of the hole is directly related to its size, but it turns out that the density of a black hole is inversely related to its mass. The bigger the original star, the less dense it needs to be to become a black hole. Super massive black holes can actually be about as dense as water, since they are so very massive. And the event horizon, the place beyond which we lose sight of you as you swirl in, is so far from the singularity at the center that a trip into the super massive black hole would take enough time to allow you to ponder your fate. In fact, scientists think that the tidal forces normally so very strong near a black hole, strong enough to “spaghettify” you (your atoms are ripped into a long strand of you as you twirl into the hole) are not so strong near the really massive black holes. So your trip into it might be somewhat non-eventful, if not pleasant. That is, if you were to be so foolish to be near such a black hole. Lest we forget, there are many dangerous things about black holes, not the least of which is the torrent of X-rays and gamma rays flooding out of the accretion disk. This is the plate of material feeding into the black hole, and it really does look like a big, gassy plate, serving up the special of the day.
If you’d like to try to see the black hole at the center of our galaxy, you will have to imagine it, for it’s shrouded by millions of stars, clouds of gas and dark nebula forming a curtain in front of it. Even if there was no curtain, you’d still be hard pressed to see it, since no light can escape their gravitational pull, making them earn their nefarious reputations of the invisible gas-eating monsters in space.
Until next week, my friends, enjoy the view.
by C. Zaitz
One of the more eyebrow-raising bits of gossip heard in astronomy circles is that most galaxies, even our own, contain a super massive black hole at their cores. A super massive black hole is much heavier than a garden variety stellar black hole, which can weigh as little as one and a half suns or as much as 14 suns. That may not sound spectacular, but a black hole with the mass of 10 suns could fit into the city of Detroit. The mass of a black hole is directly related to its size, so the heavier it is, the bigger it is. But how massive is super massive?
The monster black holes we find in the centers of galaxies tend to range in mass from a hundred thousands suns to tens of billions of suns. Some scientists suggest that they started out the same way stellar-sized holes do, but over long periods of time grew larger and larger from consuming the available material in the center of the galaxy. It seems more likely that these black holes, like the one in the middle of our galaxy, formed from a large cloud of collapsing gas, creating a massive central star, some hundreds of thousands of solar masses, which then collapsed (with no supernova) to form a gigantic black hole. Since that time it has been eating everything close enough to be drawn in. Don’t worry, though; we are very, very far from the center of our galaxy, and not in the least affected by it.
We noted that the mass of the hole is directly related to its size, but it turns out that the density of a black hole is inversely related to its mass. The bigger the original star, the less dense it needs to be to become a black hole. Super massive black holes can actually be about as dense as water, since they are so very massive. And the event horizon, the place beyond which we lose sight of you as you swirl in, is so far from the singularity at the center that a trip into the super massive black hole would take enough time to allow you to ponder your fate. In fact, scientists think that the tidal forces normally so very strong near a black hole, strong enough to “spaghettify” you (your atoms are ripped into a long strand of you as you twirl into the hole) are not so strong near the really massive black holes. So your trip into it might be somewhat non-eventful, if not pleasant. That is, if you were to be so foolish to be near such a black hole. Lest we forget, there are many dangerous things about black holes, not the least of which is the torrent of X-rays and gamma rays flooding out of the accretion disk. This is the plate of material feeding into the black hole, and it really does look like a big, gassy plate, serving up the special of the day.
If you’d like to try to see the black hole at the center of our galaxy, you will have to imagine it, for it’s shrouded by millions of stars, clouds of gas and dark nebula forming a curtain in front of it. Even if there was no curtain, you’d still be hard pressed to see it, since no light can escape their gravitational pull, making them earn their nefarious reputations of the invisible gas-eating monsters in space.
Until next week, my friends, enjoy the view.
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