Star Clusters  Back to Photo Gallery - Star Clusters
 NGC457 - The Owl Cluster 


1280 x 1278 (Mid Resolution)            1920 x 1917 (Full Resolution)

About:
NGC 457 (also known as the Owl Cluster, the ET Cluster, or Caldwell 13) is an open star cluster in the constellation Cassiopeia. It was discovered by William Herschel in 1787 and lies over 7,900 light years away from the Sun. It has an estimated age of 21 million years. The cluster is sometimes referred by amateur astronomers as the Owl Cluster, Kachina Doll Cluster, the ET Cluster (due to its resemblance to the movie character) or the "Skiing Cluster". Two bright stars, magnitude 5 Phi-1 Cassiopeiae and magnitude 7 Phi-2 Cassiopeiae can be imagined as eyes. The cluster features a rich field of about 150 stars of magnitudes 12-15 .. [Text from WIKIPEDIA]

Pubblications NASA/EOS/USRA - EPOD 17 February 2013
Optics: GSO RC 10" F8 2000mm - Astrograph Ritchie-Chrétien
Mount: AP Mach1 GTO on Gemini Q-Lock tripod
Camera: QSI-640WSG
Filters: Astrodon I Series Gen II LRGB 1.25"
Guiding Systems: SXV-AO-LF Active Optics - SX Lodestar
Dates/Times: 12 November 2012
Location: Pragelato - Turin - Italy
Exposure Details: L:R:G:B => 80:30:30:30 = > (16x5):(6x5):(6x5):(6x5) All Bin1 [num x minutes]
Cooling Details: -25 °C
Acquisition: Maxim DL/CCD, Perseus
Processing: CCDStack2,PS CS5
Mean FWHM: 2.35"
SQM-L: 20.61