Thursday, May 8, 2008

M104 and Iris?

This is my first attempt at posting a sketch. I did this the evening of 4 May 2008 in my usual fashion: with whatever pencil/pen was handy on the back of a piece of scratch paper, usually one of my charts printed from Ciel. I've decided this isn't the best approach. At any rate, this was done from my rural Rolla Missouri location under dark, no moon or clouds, sky about 10:00 pm CDT using my 8" Orion XT dob with a 25mm ep. I scanned it using Microsoft photo editor at 75 dpi grey scale, used Paint to erase all the bleedthru's from the back of my scratch paper and replaced my miserable hand-drawn circle with a machine drawn one. I actually had a compass drawn circle of decent size handy but it was too faint to see. At least my hand-drawn one was a decent enough size. My previous sketches were squeezed into little postage stamp miniatures.
My motivation for posting this turned out to be a bit of serendipity. I was reading some of the new posts at cloudynights and ran across a sketch of M104 with a note that the asteroid Iris was in the FOV. I checked it out with Ciel and, sure enough, there was Iris. Then I remembered, or thought I remembered, that I had seen M104 recently. Turned out it was the same night but several hours later as the cloudynights poster was in Europe. I checked my sketch and there is was! I'm still not possitive which one is Iris, possibly either the top one in the group of three to the east of M104 or the one above that. I need to revisit M104 when the clouds part and see which one if any moved. There are a few 10th mag stars in the sketch including the group of three but I may have missed mag 10 Iris. It should be to the NNW of M104 about 15' by tonight (5-8).
M104 was fairly dim but I was able to make out the dark lane a bit below center using my 10mm ep. I estimated its size at about 3' which is less than half the 8' given by Ciel. Perhaps I wasn't seeing the dimmer edges. There was at least one brighter speck in the center of M104.
May 4 was a good clear night with no wind and not too cold. I was able to snag M68, M59, M60, and NGC4647 as well as M104. M68 had a bit of texture with several bright specks in my 10mm. I used a black t-shirt as a hood to block out some stray light from my neighbor's yard light about 0.25 mi away. M59 and M60 both fit nicely in the field of my 25mm. NGC4647 was visible as a second bright patch just to the west of M60 in my 10mm. M60 had just a hint of some bright specks in the center with some dark texture.

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