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Tuesday, July 21, 2009

A new Jupiter impact and a deep sky pair

It's been a while since I posted, and indeed, I haven't been able to observe much lately, mostly due to the weather. I did get out to the West Virginia mountains this past weekend. On Sunday night, I got a good look at Jupiter in my 10-inch with excellent seeing conditions. I hadn't heard about the impact of an object in the south polar region, and that's not an area of the planet I usually scrutinize for detail. I did notice in passing that both temperate/polar areas were exceptionally bland. In fact, the north temperate belt was only a barely perceptible thin dim line in one area, and the STB was totally invisible. Only fine scale detail was visible in both equatorial belts- no major features.

This time, and the last time I was out in May, I observed a nice pair of deep sky objects in Scutum. How often do you find a globular cluster and a planetary nebula in the same field of view? Yes, I know- Pease 1 in M15, but come on- that's not exactly one that jumps out at you! Try going just 2-1/2 degrees SSE from M11, The Wild Duck Cluster, and you'll find 8.1 mag globular cluster NGC 6712. Just 23-1/2 arcminutes away in position angle 110 is planetary nebula IC 1295. The planetary is a large one at 90 arcseconds, and although Jay McNeil's list has it at 15.0 mag, it's clearly a lot brighter. It's easily visible without a filter in my 10-inch. A narrow band filter shows a little bit of annularity to it. The globular partially resolves in my scope, making this an interesting pair for observation even if they weren't so close to each other. I didn't find many images of this pair on the web, so it would make a nice target for astro-imagers.

If you've got at least an 8-inch scope and are up for a challenge, there is also a very small 14.2 mag planetary only about 5 arcminutes from IC 1295. This is Kohoutek 4-8 (plotted on my software as PLN 25-4.1). It is visible in Chris Schur's image if you click on one of the higher resolution images. Find the little arc of five stars about 1/5 of the way from IC 1295 to NGC 6712. It is the middle star in the arc. Looks like a star, so you can blink it with an O-III filter to be sure. I did not try for it in my 10-inch, though I might next time out as it's pretty bright. You just need to have an image or very detailed chart to guide you to the right one.