November 6th, 2007

Comet 17P/Holmes

Astro-images of the day: Comet 17P/Holmes

I just finished editing these photos that I took all by myself with my new CCD camera and tmseay's Celestron 8" SCT telescope with clock drive! These are the first astrophotos that I've taken in years... well, more accurately, in decades! And my first digital astro-photos ever. I'm so excited. They're not great, but I'm only just learning how to use the camera. Plus, I didn't spend the time necessary to properly align the telescope for long exposures.

Okay, onto the photos. This first one gives a good idea of what you would see through a telescope with your naked eye (only it's actually prettier in person - odd for astro-images!):

Comet 17P/Holmes photo by Chris McKitterick, 4:17am US Central time, November 6, 2007.
Equipment: Celestron 8" Schmidt-Cassegrain at prime-focus using Meade Deep Sky Imager CCD camera; 15-second exposure.

With your naked eye, what you see looks much like a jellyfish without tentacles: Very smooth curve on the left side swooping around to the "back" (bottom-right), where it gets diffuse - the starts of a tail, methinks! Anyhow, the jellyfish has a sort of bubble-within-a-bubble shape, the outer bubble not quite as bright as the inner, so you can see it glowing within. At the core blazes the comet, itself, very bright in this image (not quite as much with the unaided eyeball).

I watched it with my Orion XT10" Dobsonian reflector, as well, and found that its short F/ratio (F/4.7 vs. the Celestron's F/10) liked a 15mm eyepiece best. The view through that 'scope was just amazing, with the shells much more contrasty. But without a clock-drive, I simply wouldn't be able to take a photo (the Earth spins too fast, magnified by the 'scope's magnification). I can't tell you how much I'm now looking forward to when my new Meade 12" SCT with GPS precision drive! arrives in a month or so, because then I'll be able to take super-long exposures! Ooh, I'm getting so excited!

I also took a few more photos of various objects including Mars and the Orion Nebula, but they didn't turn out very well. That clock-drive precision-issue again. It was such a geeky experience to be sitting outside with two chairs - one for the laptop and one for me - with USB cable coiling up from the laptop to the CCD camera and extension cord running from the 'scope's base all the way to a plug on the back of the house. I sat there looking at my computer screen (dimmed way down, of course), adjusting the image up-down and side-to-side in real-time while setting exposure (and having to wait that many seconds to see if the image was going to turn out) and centering the object and so on... lots to learn! The setup looks a lot like this, only with an orange telescope:

I began my education by using Mars because it was so bright that I could use Live mode rather than waiting for an exposure to show up. But it was so much fun, despite the 20°F (with wind chill) weather. Oh, and my fingers only now have warmed up; at some point not long after these shots, my fingers could no longer accurately type on the keyboard because they had lost all feeling (ever tried typing on a laptop while wearing gloves?).

Here's another goofed-up shot that I think looks cool. Same comet! Wacky results from a beginner with a CCD camera and too many photo-options!

Comet 17P/Holmes photo by Chris McKitterick, 4:21am US Central time, November 6, 2007.
Equipment: Celestron 8" Schmidt-Cassegrain at prime-focus using Meade Deep Sky Imager CCD camera; exposure unknown!

Oh, and here's where you can find the comet right now. It's really easy to find with your naked eye any time, say, an hour or two after sunset to very late in the night (obviously). The comet is as bright as the two nearest stars in Perseus, and more diffuse. In a binocular or low-power 'scope (like the finders on mine), it's clearly a ball of gas and dust rather than a star):

Click the image to see the story.

PS: Mars looks gorgeous right now! It's the brightest thing in the sky, and using my 10" telescope with a dash of patience, I caught glimpses of dark surface detail every so often. Oh, and it's in almost-full gibbous phase.

More photos as I take 'em!


30% off today only at the KU Bookstores!

Geez, I almost forgot to remind y'all!

Because the KU football team stomped all over the Nebraska team last weekend (something like 1357 to 6), you get 30% off of KU merchandise, school and art supplies, and general books on the following Tuesday - that's today!

Click the image to see the sale details.

The fine print:
Discount will be applied manually after checkout. Sale valid at all KU Bookstores - Kansas Union, Burge Union, Edwards Campus, Oread Books, and the Art and Design Shop. Offer does not include textbooks, electronics and sale items. Offer not valid with other discounts or offers.