Log, Mar 31, 2006

44 people. The operation of the Observatory has begun to swing from its winter mode to its summer mode. This isn't so much what is the sky and what the equipment needs to run but a change in the way people visit us. During the summer we get two crowds, the early crowd which seems to be people who want to look at a few things and then take the kids home followed by a group of more ambitious viewers. Such was the case tonight.

Early on, I displayed a bunch of crowd pleasers. The Moon was a thin (9%) sliver of brightness against a nearly complete disk of blue gray semi-light. This effect is called the "new Moon in the old Moon's arms". What it really is, is an alignment of the Sun, the Moon and the Earth such that sunlight hits the Earth (mainly the Pacific Ocean), bounces off the Moon and returns yet again to be seen by anyone looking up. Later in the lunar cycle, light from the Earth misses the Moon entirely. Thus we do not have something like "a first quarter Moon in the last quarter Moon's arms". That is lucky because that last phrase is truly an ugly term!

Mars was popular with the kids who all looked to see if they could find the whitish area where the polar snows were. Little detail could be seen, and in truth the viewing at this point in the night was poor. M42 was somewhat better, but the star images were enlarged by atmospheric conditions here on Earth. Still for those of us who knew how to look for it, we could see not only the four brilliant new stars but the fainter E star. The F and G stars were simply not visible. I went to Saturn as soon as it was low enough to clear the Dome's shutter. It was the source of many "wows!" and other exclamations of approval. At least five of Saturn's moons were easily seen, and a few of us could make out a very dim sixth moon (Mimas). The very dimmest of the potentially visible moons (Phoebe and Hyperion) were not visible at all. I had to explain that several fairly bright "moons" were actually background stars. However I think several kids still believe they saw nine or more of Saturn's sixty

Spring brings the Virgo-Coma Bernices Super Cluster of galaxies, sometimes called the "Realm of the Galaxies" into center stage. These galaxies were surprisingly mediocre tonight for a moonless night. Even bright galaxies like the incredibly huge elliptical galaxy M87 (Virgo A) was competing for The Smudge of the Week Award. I tried M5 and M13. They were a bit better but usually M13 is great and tonight it was ho-hum.

After the crowds were gone, several visitors who had set up an 8 inch scope up outside came in. They wanted to Schwassmann-Wachmann, a comet which is breaking apart as it nears Earth. Ernie had some coordinates for the comets which were not exactly the coordinates I usually use, and it took some diddling (and a bit of dumb luck) for me to figure out how to enter these coordinates into the telescope's computer memory. We got a view of this unusual comet biggest piece.

Frosty Drew will be closed Friday April 7th. I will be overseas this weekend.

-Les Coleman

Leslie Coleman
Leslie Coleman
Entry Date:
Mar 31, 2006
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Leslie Coleman's Log
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