Many comets are blue-green in color due to Swan band radiation. This was thought to be caused by cyanogen gas many comets emit. Today we know this isn't really true. The color is due to fluorescence of carbon particles rather than the cyanogen gas itself. But comets do emit cyanogen gas. When it was announced that in 1910 we'd pass through the tail of Halley's comet and it emitted cyanogen gas, same as used in gas chambers there was panic. My grandfather worked in a theater in NYC at the time. Suddenly in January the Great Comet of 1910 appeared and most thought it Halley and they were about to die. So he and my grandmother made sugar pills in their hotel room and sold them in the theater lobby for $10 each. Admission was only 75 cents so this was a small fortune. They were guaranteed to protect you from the gas. My grandmother worked 19 hours a day making pills and they sold some $300,000 worth -- after the theater and magic act he worked for got their cut. That was about 50,000 pills all handmade by my grandmother and a couple maids they hired. They then retired to a house full of servants in Omaha. In 1913 the Easter Sunday tornado lifted their 4 story mansion off its foundation and carried it a block setting it down on another mansion. Then a third was deposited on them. They were 10 days in the mess before rescue as no one was considered alive in the area. They were the only survivors from that 2 block area. Near death, they somehow survived. My mother was 2 at the time. She was apparently the result of their celebration over selling so many pills. Anyway, they rebuilt but being underinsured it cut into their fortune. My mom only had 3 servants after that to wait on her, not 6. Oh yes, those 6 died as they were in the basement. My mom and my grandparents were on the stairs between the third and second floor heading for the basement but luckily didn't make it. The basement was exposed when the mansion flew away and yet another house crushed those in it. My mom's luxury life suddenly ended with the '29 crash. My grandfather was sent back into the workforce leaving them with no servants and barely a roof over their head. Easy come easy go. Much like comets.

The comet is much larger in this photo than you'd have seen in a scope or binoculars. This was taken July 11, 2007. The photo has been reduced and cropped. Image scale is 2" of arc per pixel, half my normal scale. The nucleus of the comet is hidden in the bright spot in the center and is only a mile or so across. Just a microscopic dot at this scale.

The stars are lines because I had the mount tracking the comet rather than the stars. It is moving rapidly against the stars and rather close to us as well. The color frames show up as the stars are colored red green and blue. I used two of each after I took 20 luminosity images. Each is a one minute exposure. The gaps in the white trails are due to the time it takes to download a frame to the computer -- about 10 seconds. The bigger gap is because I took the shots in two 10 minute groups and wasn't around to restart it immediately. Then I had to set up for color making for other gaps in the stars. The comet is moving southwest so the stars appear to move up and to the right, northeast.

Image is at 2" per pixel.

14" LX200R @ f/10, L=20x1', RGB=2x1', STL-11000XM, Paramount ME