Five
Newbies And An Old Friend
On
the night of May 5th I was able to make it to the
observatory for a little over an hour's worth of imaging. On my list
of Messier objects left to image (18 remaining), I imaged 5 of the
18. The Old Friend was M13, the globular cluster in Hercules that,
with M22, are probably the most impressive clusters in the night sky.
I really enjoy them. Unfortunately, Georgia is in the midst of daily
smog alerts, so the sky is anything but transparent, and that shows
up in the images, or at least in the difficulty is processing the
images to reduce the skyglow from the scattered ground based light.
At the least, these were more interesting to process for that reason.
This
group also includes M40, which has been describes as Messier's one
mistake. M40 is a double star in Ursa Major (the Big Dipper).
According to Wikipedia, Johannes Hevelius described a nebulosity in
the area of M40, which Messier looked for. Not finding any, Messier
cataloged the double star instead. Speculation is that the nebulosity
that Hevelius saw was NGC 4290, which is a dim galaxy that could be
seen in larger telescopes, but perhaps not in Messier's. When I image
star clusters or, in this case, a double star, I always take as short
an exposure as I can, usually 10 seconds. This is the case for the
image showing the double star, which, by the way, is just an optical
double, meaning the stars are actually very far from each other and
not gravitationaly connected (orbiting each other). The second image
is a one minute image which shows not only NGC4290, but NGC4284 as
well. The effects of the light pollution are also evident, showing up
as the “fog” or gray background in the image. This is the very
well known property of light pollution; it essentially removes the
black sky, substituting gray and thereby significantly reducing
contrast between the dim nebulae and the sky. The result is that the
nebulae almost disappears; visually, it actually does disappear.
The
rest of the images are as noted under the image. Just the “usual”;
galaxies and star clusters. Even though “usual”, I still marvel
at God's handy work. All made from the same star stuff, but all
different, individual; just like people.
M40 (2 stars near center). Actually NGC4290 IS faintly visible in this 10 Second exposure. |
M13. Old Friend. In Hercules, just rising in the east when taken 1 Min exp. |
M83. Galaxy also in Hydra. 1 Min exp. Low in southern sky and in heavy light pollution. |
M101. Galaxy in Ursa Major. 1 Min exp. This would be in the North, light pollution not as bad. |
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