GREEN COMET: Comet Lovejoy (C/2007 E2) is not quite bright enough to see with the unaided eye, but the sea-green comet is a lovely sight through backyard telescopes. Using a 6-inch refractor, John Chumack took this picture two nights ago:
"Several little galaxies are visible in the background," notes Chumack. "Look below the comet's tail."
Comet Lovejoy enjoys minor fame for the method of its discovery. Australian Terry Lovejoy found it two months ago using no telescope, only a digital camera (a Canon 350D). The comet's gaseous head, glowing about as brightly as an 8th magnitude star, is one and a half times wider than Jupiter. This comet is big! It is green because it contains cyanogen (CN), a poisonous gas, and diatomic carbon (C2). Both substances glow green when illuminated by sunlight in space via a process called resonant fluorescence.
You can find Comet Lovejoy this week gliding through the constellation Draco, high in the northern sky after sunset. A good night is May 14th when Lovejoy passes right by the 2nd magnitude star eta Draconis. The star will guide you to the comet.
[link to www.spaceweather.com
Cyanogen is a chemical compound (CN)2. The CN entity behaves like a halogen. Cyanogen molecules consist of two CN groups (analogous to diatomic halogen molecules, such as F2, Cl2, Br2, or I2). The two cyano groups are bonded together at their carbon atoms: N≡C−C≡N. The word “cyanogen” may refer to a single cyano group in some molecules that are considered derivatives of cyanogen. Cyanogen chloride (NCCl), for example, is considered (for the purposes of naming) to be cyanogen with one cyano group replaced with a chlorine atom.
At room temperature cyanogen is a colorless gas with a pungent odor. Its melting point is −27.9°C (−18.2°F) & its boiling point is −20.1°C (−4.2°F). Its density is approximately twice that of air at the same temperature and pressure. Like most cyanides, it is very toxic, as it undergoes reduction to cyanide, which binds more strongly than oxygen to the cytochrome c oxidase complex, thus interrupting the mitochondrial electron transfer chain. [link to en.wikipedia.org
cyanides, it is very toxic, as it undergoes reduction to (( cyanide ))