Cosmic Coathanger

Cosmic Coathanger

Cosmic Coathanger

Bad Astronomy
The entire universe in blog form
Dec. 23 2008 5:00 PM

Cosmic Coathanger

Today's Astronomy Picture of the Day has one of my favorite asterisms in the whole sky: the Coat Hanger Cluster, aka Brocchi's Cluster or Collinder 399. The image they posted is gorgeous, but copyrighted, so go there to see the nice high-res version. But to give you a low-res idea, here's a shot that's on Wikipedia:

Phil Plait Phil Plait

Phil Plait writes Slate’s Bad Astronomy blog and is an astronomer, public speaker, science evangelizer, and author of Death From the Skies!  

Coat Hanger cluster, aka Brocchi’s cluster, aka Collinder 399
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I love this object, because - let's face it -- it's a coat hanger! It also holds a special place for me because I spotted it by accident when I was but a lad and using my telescope to sweep the summer skies. I remember looking through the finder 'scope, which had a wide-ish field of view, and suddenly a clump of brighter stars moved past my sight. I maneuvered the lumbering 'scope back a little bit, and there it was. I laughed and laughed; it was a perfect coat hanger in the sky! The stars making it up are a bit brighter than the background stars, and the asterism (a collection of unrelated stars making a pattern) was so obvious and so perfect I couldn't believe it.

This was before the internet, so I wasn't able to go online and look it up. I sometimes wonder what it's like to be an amateur astronomer just starting out now, being able to sit and within seconds find information on almost anything you're likely to see floating among the constellations. And now, of course, even small telescopes are computerized, so you can type in a name and whizzzzzz! The 'scope will slew right over to the object. That's very cool, and quite a time saver (no small consideration when it's cold).

But it also means that someone today might miss out on the Coat Hanger, and that would be too bad. There are dozens, hundreds, of such things in the sky, and I can't possibly write about all of them. But if you own a small telescope, I think the very best thing you can do is dress warmly, go outside, and just have fun. You have a magnificent tool in your hands that people centuries ago would have cheerfully gone to war over, and all you have to do is go outside.

So go outside. Look up. See what there is to see.