Sunday, February 27, 2011

M45 hot blue stars and reflection nebulosity in all their splendor!

M45 hot blue stars and reflection nebulosity in all their splendor!
Click on the image to enlarge

The Pleiades, or Seven Sisters (Messier 45, or M45), is an open star cluster containing middle-aged hot B-type stars located in the constellation of Taurus. It is among the nearest star clusters to Earth and is the cluster most obvious to the naked eye in the night sky. Pleiades has several meanings in different cultures and traditions.
The cluster is dominated by hot blue and extremely luminous stars that have formed within the last 100 million years. Dust that forms a reflection nebulosity around the brightest stars was thought at first to be left over from the formation of the cluster (hence the alternate name Maia Nebula after the star Maia), but is now known to be an unrelated dust cloud in the interstellar medium that the stars are currently passing through. Astronomers estimate that the cluster will survive for about another 250 million years, after which it will disperse due to gravitational interactions with its galactic neighborhood.
This image is a composite from black and white images taken with the Palomar Observatory's 1.22-meter (48-inch) Samuel Oschin Telescope as a part of the second National Geographic Palomar Observatory Sky Survey (POSS II). The images were recorded on two type of glass photographic plates - one sensitive to red light and the other to blue and later they were digitized.
In order to produce the color image seen here, Davide De Martin worked with data coming from 2 different photographic plates taken in 1986 and 1989. Original file is 10.252 x 9.735 pixels with a resolution of about 1 arcsec per pixel. The image shows an area of sky large 2,7° x 2,7° (for comparison, the full-Moon is about 0,5° in diameter).
Credit: Caltech, Palomar Observatory, Digitized Sky Survey
Color composite, copyright: Davide De Martin

0 comment(s):

Post a Comment