dimanche 31 août 2008

Crater 6

Crater, was the Cup that Corvus used to bring water back to Apollo. The Cup has been connected with many other legends as well. Crater the Cup is one of those constellations that is remarkable simply because it is so unremarkable. It contains a quiet corner of sky. There are no good observing targets for beginners. The stars in Crater are no brighter than magnitude 3.56. Most of the galaxies in the constellation are magnitude 12 and dimmer.
Crater the Cup is perched on the back of Hydra, the water snake. Also sitting on Hydra's back and right behind the Cup is Corvus the Crow. In mythology, Crater was the cup from which Apollo drank. Apollo was a well-known Greek god whose job it was to carry the sun across the sky each day. As you can imagine, it was a hot and laborious task. Apollo asked his pet crow, Corvus, to fetch him some water to drink because he was tired and overheated. But Corvus was not a good pet and did not do as Apollo wished. Corvus flew away on his mission and while gone he saw a tree with berries. He spent a couple days eating the berries before finally returning with the water. He also brought along a water snake, making up a story that the water snake attacked him and this was the reason for his delay. Apollo didn't believe his lie and placed him in the sky by the cup. Now it's payback time for Corvus the Crow, who always has the cup in his sights but can never drink from it himself.
Crater can be found below the head of Virgo and below the tail of Leo. Its brightest star is Delta Crateris at magnitude 3.56. Delta Crateris lies 195 light-years distant. Gamma Crateris is a magnitude 4.05 star lying 89 light-years away. Slightly dimmer is Alkes, or Alpha Crateris, at magnitude 4.08. It lies 174 light-years away. The Beta star is a dim 4.46 magnitude lying 266 light-years away. All would be hard to see in urban and other light-polluted locations.
There are no Messier objects in Crater. There are a number of galaxies from the NGC and IC catalogs, with NGC 3887 and NGC 3511 and 3513 being the more often observed items. NGC 3887 lies between Crater and Corvus. It is an 11th magnitude barred spiral. NGC 3511 and NGC 3513 are only 11 arcminutes apart and lie in the southwest corner of the constellation. These 12th magnitude galaxies can be seen in the same field of view of a large telescope.

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