M46 is a rich open cluster, easily visible with binoculars, that is located in the rich Milky Way star fields of the constellation of Puppis. The cluster is a relatively large object with an apparent diameter almost equal to that of the full Moon. Charles Messier discovered M46 in 1771.
M46 is 5400 light-years distant, with the non related planetary nebula closer at 3000 light-years.
Find a close-up on the planetary nebula NGC2438 here.
Ha-O3-LRGB (Ha 4x40m, OIII 4x40m, L 6x10m, R 7x100s, G 7x100s, B 7x100s), seeing 0.7 arcsec
80cm f/7 Astrooptik Keller corrected cassegrain, FLI Proline 16803, Baader Filters, Prompt 7 CTIO Chile,
Acquisition: Philipp Keller, Processing: Johannes Schedler