Thursday, 5 September 2013

Stunning galaxy group NGC 7172 by Steve Crouch


Steve Crouch has come up with this pearler of a galaxy group, with NGC 7172 showing beautiful dust lanes and colour. Look closely and you'll see at least 40 galaxies in this single photo! With an average of 100 billion stars per galaxy, that's a heck of a lot of stars...
Catalogue and alternative designations NGC 7172 galaxy group, Hickson 90
Type  Compact galaxy group 
Position 22 02.0, -31 52
Constellation Piscis Austrinus
Camera and Telescope STXL11002 and 36.8 cm Ritchey Chretien Focal Ratio F9
Exposure Details LRGB 225:45:40:40 Luminance binned 1x1, Colours 2x2 with Baader filters
Description
This little group of galaxies doesn't seem to be imaged much.  NGC 7172 is lower left of centre (with the dust lane). NGC 7173, 7174 and 7176 form the interacting group just above centre.  ESO 466-46 and 466-47 are to the lower right.  The bright star is magnitude 6.7.
Galaxies range in size from 10 million stars up to 100 trillion! And there are some 170 billion galaxies in the known observable universe... Incomprehensible numbers.