Even the best laid plans sometimes go right ;-)

Shortly after 7 am yesterday I sent out a notice to the group planning to visit that night saying “this is going to be an iffy day - right now I expect it to be mostly clear this morning, cloud up this afternoon, then clear up again around 7 or 8 at night.”

My forecast was based on what the Clear Sky Clock was saying. Darned that thing is good! As I wrote the message it was clear – but by mid morning it was clouding up. Since this was to be their first visit, they said they would come no matter what the weather so they could at least learn to use the telescopes and binoculars. At 8:30 when they arrived there was a cold wind, and 90 percent cloud cover. We spent the last half hour of twilight learning how to use the telescopes. Then as they got to the point where they understood how to aim them, one of the children said they thought they could see stars in the finder scopes.

I looked up and sure enough, a few holes were developing. Fortuitously, one of the holes was high in the west where Saturn was shining all by itself. I told the group to see if they could find that “star” with the telescopes and a few minutes later I was rewarded by an excited question: “is THAT Saturn.”

You bet it is. And while it’s one of the coolest things to see in the entire sky, I think of how much more fun it is to point a telescope for the first time and discover you’ve hit gold dust – ringed gold dust, that is. As others gathered round the telescope Cara was using, I encouraged them to use the other scopes to find it themselves. Soon each of the three small Dobs was pointed at Saturn and this small group of two adults and three children were learning about how different eyepieces give different powers and how that bright little “star” next to Saturn was really its largest moon, Titan.

Meanwhile, darned if the clouds weren’t clearing out altogether and I gave the Clear Sky Clock a silent blessing for once again being correct. I was able to put to use the clipboards I had prepared with observing instructions, questions, and space for making little drawings.

I had hoped that some time during the evening they would get a peek at Saturn, but my real plan was to help them explore the idea that stars tend to hang out with other stars, so I gave them the Mizar challenge. What’s that? When you look at Mizar, the star in the middle of the Big Dipper’s handle, how many stars do you see? Try it first with the naked eye, then with binoculars, then with the telescope. Draw the final result. Mizar, of course, is a wonderful multiple star system. Later, using the 15-inch, we looked at M13, a globular cluster, and M51, a pair of galaxies in collision.

Here’s what I hope the group got out of the entire experience – including a serendipitous little side trip to Jupiter.:

1. The major purpose of an astronomical telescope is to gather more light than our eyes can see. This means the telescope helps us see things that are very faint and very far away. Magnifying what we see is important, but not nearly as important as gathering light.
2. Saturn, with its rings, is really beautiful. Jupite , with its dancing moons and color bands, is big!
3. Stars are huge and only appear small because they are very far away. Most of the brighter stars we see with our naked eye are about 100-to-1,000 light years away.
4. Stars can be “singles” like our Sun – but frequently they are doubles or triples. Sometimes they are like little families, all held together by their gravity and traveling together through space.
5. Some stars gather together in globular clusters. Scientists think most of these are very old stars – at least twice as old as our sun. One of the biggest and brightest globular clusters is M13 in the constellation Hercules. It is about 25,000 light years from us and contains about half a million stars.
6. Stars – whether alone or in globular clusters – gather together in huge collections called galaxies. Our galaxy is the Milky Way and contains about 100 billion stars. With the big telescope we looked at two galaxies in collision. It’s called “M51” or “The Whirlpool.”
7. Numbers in astronomy are so huge they are hard to really understand. It’s easy to say “million” or “billion,” but hard to understand how different those numbers are. One way is to remember two simple numbers- 11 and 33. If you counted every second for 11 days you would reach one million. But it would take you nearly 33 years to count one billion seconds.
8. Your bare fist, held at arms length, covers about 10 degrees of sky. Witht his you can make rough measurements thathelp you find things.

If I had to pick out a favorite moment from last night, it was when Cara discovered that the “star” she had found was really Saturn! But I was delighted with how well they all did in using the big binoculars and telescopes to find Mizar and Alcor. That was not easy. When something is as high in the sky as Mizar was at that moment, it’s much more difficult to successfully point the telescopes and binoculars, but they all did it.

I really didn’t think we would see Jupiter because it is low in the south and my tree line to the south is high. But as the last person looked at M13, I noticed Jupiter had reached a small gap between trees, so I pointed the telescope at it without telling anyone what they would see. I asked each to go to the scope, take a good look, but outside of “oohs and ahhs” not to say anything. To me Jupiter was obviously Jupiter and this was an unusually knowledgeable group who seemed to have done their homework before arriving. Without my caution I expected each to blurt out something about Jupiter. Still, after everyone had taken a look I asked what it was they had seen. Most didn’t seem to know, Some thought it was a big star. One said a planet. Finally someone came up with Jupiter.

Yep,it was Jupiter, and you could easily see three of the bright moons Galileo had discovered nearly 400 years ago. But what was neat was one of the childfren went back for a second look and I asked her if she could see the moons. She surprised me by saying she could see one almost touching the planet. I took a quick peek. Well I’ll be darned! There was Io popping out from behind the planet! What wonderful timing. So when they first looked they saw three moons. When they all took a second look, they saw four, nicely illustrating how rapidly the moons change position – one of the fascinations of watching Jupiter with a small telescope.

What we saw looked like this:

“I” is for “Io” and that’s the moon that popped out as we watched. The other moons we saw are Callisto, Europa, and Gannymede. (The image is taken from the Jupiter moon simulator at Sky and Telescope’s web site.)

Bottom line. I’m used to making detailed plans in preparation for visitors. I’m also used to only covering about half the ground I intend to cover and having to change my plans somewhere in the middle of the evening. Tonight started out like everything was going to go wrong – instead, everything went right with at least one unanticipated highlight – the little hide-and-go-seek routine pulled by Io.