The constellation Puppis is depicted in this image. It contains a number of notable objects, including the open star cluster "M46" seen near the left edge of this image. This round cluster contains up to 500 stars, and spans some 300 light years. The stars are relatively dim because of the cluster's distance (5,300 light years) from Earth. Note the small pink circle at the top of M46. This is planetary nebula NGC 2438. A planetary nebula consists of the remnants of a star that exploded thousands of years ago. We are witnessing the expanding shell from that explosion, illuminated by the very hot stellar remnant at its core. It is still unclear whether the exploded star was a member of this cluster. The best, and most recent, evidence suggests that it is.
February 22, 2015
Location Taken:Siding Spring Observatory, NSW Australia
Conditions of Location: Equipment Used:Planewave 20" corrected Dall-Kirkham telescope, FLI PL6303E camera
Processing Used:3 minutes x 8 x luminance, 2 minutes x 8 x RGB, for a total exposure of 75 minutes, processed in Photoshop and Maxim DL
Distance from Location:5,300 light years
Constellation:Puppis (the "stern")
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