In the last year I have made beautiful shots of the open clusters of the winter sky, enriching a specific folder. Among the various I like this mosaic in which there are four groups (M46 on the left, NGC 2423 on the top right, M47 on the right, NGC 2425 on the bottom towards the center) and some small planetary nebulae (not appreciable at this magnification, except for NGC 2438 superimposed on M46). Zooming in, just north of M46 you can see the small planetary nebula PN M 1-18, recognizable by its small red disk.

Messier 46 (M46) or NGC 2437, is an open cluster of stars in Puppis constellation at about 5,000 light-years. The planetary nebula NGC 2438 appears on its northern edge, but it is unrelated with the cluster. Messier 47 (M47) or NGC 2422, is an open cluster in Puppis constellation at about 1.600 light-years. NGC 2423 is an open cluster in Puppis close to M47 at about 2,500 light-years. NGC 2425 is a small open cluster (5 arcmin size) in the Puppis constellation at 3,500 light-years. NGC 2425 is a 2.2 Gyr old cluster, probably of solar metallicity.