Comets are very peculiar objects. In fact, they're nothing more but large, dirty snowballs that follow very strange orbits around our sun. Most of them don't even have a fixed orbit at all. They come to us from the edge of our solar system, make a swift pass near the sun and then disappear into the depths of space again forever. As they approach the sun, the radiation and solar wind make the ice and dust evaporate, creating the well-known tails. Currently we have registered over 5.000 comets but scientists guess that the number of comets hiding in the so-called Oort cloud, a suspected cloud of icy bodies at the theoretical edge of our solar system and even far into interstellar space, would reach 1 trillion.
On average there's a comet visible to the naked eye roughly once a year, but most of them won't blow you out of your socks. They're just small and incredibly faint blobs in the sky. The Panstarrs comet which is currently transiting our evening skies and became the subject of this drawing, can only be seen with a good pair of binoculars under a dark sky. But every once and a while comets do make a lasting impression. The most famous one is of course Halley's comet which pays us a visit once every 75 years and is due to return in... 2061. As I remember, its appearance in 1986 was a bit disappointing but let's hope that our children'll have a better opportunity to see it.
Comets are also responsible for a phenomenon that's probably even more spectacular. Their tail leaves a long trail behind of dust and rocky particles. When the Earth subsequently passes through this trail, the particles fall into our atmosphere and burn up in a big flash. You've guessed it! They cause the great meteor showers that we can see every year! The most famous of those are the Perseids which reach their peak around the 12th of August and are debris of the comet Swift-Tuttle. But also other meteo showers can be quite spectacular such as the Leonids, Geminids and Quadrantids. During these showers it's easily possible to see a meteor - popularly named a "falling star" - every minute, or sometimes even more.
During my observation of Panstarrs I immediately noticed its slightly elongated form, but I couldn't make out a real tail. Also its small but bright nucleus really stood out. Unfortunately there was a lot of wind yesterday which made the observation difficult and if that wasn't bad enough also the local football team decided to practice. The football field's located about a mile off and twohundred metres down in the valley but the bright lights still managed to spoil my southern sky. But here it is...
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