- Alice's Astro Info - https://alicesastroinfo.com -

Comet Holmes (a.k.a. 17P)

Don’t miss Comet Holmes – visible tonight, and possibly all of November. It’s starting to dim down though, so go outside and check it out as soon as a clear night comes along.

This is a photo my husband and I took last night (November 5, 2007) through our little 4-5 inch Celestron NexStar telescope. It’s not very bright, but you can see the off-center bright spot in the middle.

Finding the Comet:

To find it, you’ll look for the constellation Perseus. At about 8pm tonight, look east. You’ll see a fairly bright star above the horizon. That’s Capella. Look above it. Before you get to the next brightish star there will be a smudge. You’ll think it’s a star. It looks like someone just tried to erase a star with a bad eraser that left a mark behind. That’s the comet.

You can see it from the city, with streetlights shining in your eyes – but the darker it is around you, the better it will be. If you have binoculars or a telescope, use them to see more detail.

What the Scientists Think:

A fascinating thing happened to 17P (the name assigned to the comet by scientists): two weeks ago it was invisible to the casual observer. You needed a pretty good telescope to find it. Then, on October 24th it suddenly became a lot brighter. Now, all eyes are on it, without any ‘scopes or binoc’s. Turns out, this is an exploding comet!

You can see in the images (and in binoculars) an expanding cloud around the center of the comet. This is a dust cloud that the comet spit off when it exploded. According to Sky and Telescope, this isn’t the first time this comet has exploded: when Mr. Holmes discovered this comet (115 years ago) it was exploding. Then it exploded again! This is the third time in recorded history that this comet has become so spectacular.

I don’t think it’s so strange for a comet to explode – they’re constantly off-gassing (small explosions of released gas) because of they’re made of ices that heat up and sublime as they approach the Sun. This comet just seems more volatile than most. Keep an eye out though: science may say something different about this comet when we learn more.

Take this chance to look at one of the five most exciting comets of the decade! Go out tonight! Keep looking up.

Want More?
Where to find it: http://www.skyandtelescope.com/observing/home/10862521.html
The best photos: http://www.cometography.com/pcomets/017p.html
Make a comet at home: http://www.noao.edu/education/crecipe.html
(QFC is a local place that sells dry ice)