Thursday, February 26, 2009

An Evening With Comet Lulin

There is nothing like something exciting happening in the sky to bring out bad weather. In reality, the weather hasn't been bad, just cloudy, and not really solid overcast, but just enough to spoil any real chance of imaging the bright comet that currently graces our sky.

So blue sky finally broke through today, and even though it was a "school night" I had to go out and image. The comet is very nearly closest to the earth at about 40 million miles and also at opposition to the sun, so it is observable all night long. It is also moving very quickly - about 5 degrees per day, providing a good chance to do some sequences showing it's motion.

Melinda had to work tonight, but Ed, a friend visiting from Saskatchewan, joined me for the trip out near Kitt Peak. We arrived after dark, and I hurried to set up the 14" Celestron and Hyperstar for imaging. After that was finally going, I set up a second camera on a portable mount with telephoto lens. So here are the quick and dirty results - no stacking, no tricks other than some brightness and contrast adjustments. The first one is with the 200mm telephoto - 4 minutes exposure at F/3.2 on the Canon XSi. It shows a pretty wide field with the star Rho Leonis to the upper right, north is up. The closer view is with the 14" Celestron + Hyperstar = about 660mm focal length at F/1.9. It is a 1 minute exposure with the Canon 20Da camera. I've got a few frames to play with stacking to reduce noise, or make some short movie sequences, but I've only got a minute before going off to sleep, so this is what you get.

Recent reports describe the comet as a Q-tip, but Ed thought it looked like a lit match, and I might have to agree with him. Lulin was visible to the unaided eye, but wasn't blindingly so. The view through the 9X63 binoculars closely resembled the telephoto view, though color was hard for me to detect. Over the course of a couple hours, I thought I could definitely see it getting closer to Rho, so naked eye detection of motion was easy too. By the way, there are some spectacular images at Get out and see it first hand if you get a chance - I'll likely be doing the same!

1 comment:

Shannon and Alex said...

Seriously. Completely cloudy here. Good thing I have an astronomer/photographer uncle on hand who blogs.