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.

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.

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.

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.