A guide to what's up in the sky for Southern Australia

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NGC 2439—Open Star Cluster (1st Feb 2026)

NGC 2439—Open Star Cluster - Distance: 12,500 light years

NGC 2439, discovered by British astronomer, John Herschel, on 28 January 1835, is an open cluster located in the constellation of Puppis, just south of Sirius. The cluster contains approximately 600 stars and is believed to have formed out of a giant molecular cloud about 200 million years ago.

With an apparent size of 10 arc minutes, it occupies an area of sky one third that of a Full Moon. Binoculars with show the brighter stars, but a telescope will provide a more satisfying view.
Interstellar reddening towards NGC 2439 is significant, primarily due to the dust in the line of sight within the galactic plane.

This extinction has made distance determination difficult. The red supergiant star R Puppis may be a member.