I am way behind processing and posting images taken at Dogstar Observatory. The work of taking astronomical images is like keeping a high performance race car in top condition. It is mostly an engineering challenge keeping all the myriad electronic, mechanical and software products working together. Processing and publishing images is more like artistic expression. Each finished image involves processing as many as one hundred individual images taken in the various colors (red, green and blue typically) and then using complex and user unfriendly software to turn them into something nice to look at. All of this, of course, is just an excuse for my tardiness in getting images on the Dogstar web pages. Occasional I go back into the files and see if there is something interesting to look out that does not require much processing. While going through my files from the winter and spring I came across this interesting single (i.e. black and white) image of some of the Milky Way’s neighbors taken this past May. Its part of the Virgo cluster (since it appears to be in the constellation by the name) and sometimes goes by the name Markarian’s chain. The galaxies in this image (M86, M84, M98, M101, NGC 4477, NGC 4473 and others) are just a tiny part of the Virgo cluster which contains over 1300 galaxies. Each of the galaxies contain on the order of 200 billion stars.
The streak through the image is not a scratch (although there really is nothing to scratch with digital photograph) but rather its a satellite. Like one of the thousands of weather, mobile phone or spy satellites that orbit close to the earth. If you look closely you can see that the trail brightens and dims indicating its probably tumbling in its orbit.