I will, I promise, quit talking about Comet Lulin very soon. You can't really see it anymore, as it begins its lonely multi-million year journey back to the Oort Cloud, so there's not much left to say. But it was such a pretty one, with all that green and those two tails and such, I have to post one more thing. This is a video stolen from the ever-reliable Bad Astronomy site, a time-lapse of rock and ice and gas pouring off the head of Comet Lulin. It looks like a smoking matchhead to me. Makes me want to light up a cigarette.
Eric recently asked me what made the comet green, and I looked it up to give him an answer (he called me Mr. Wizard, gently assuaging my ego, so I couldn't say no). It's cyanogen gas, a poison related to cyanide. So the "smoke" in the video coming off the comet actually contains a deadly gas. It's pretty common in comets. There have been scares in the past that going through a comet's tail would kill us all - notably in 1909 when Halley's Comet came around - because of the cyanogen.