6th magnitude. Messier 93 (M93) is another open cluster somewhat to the south. NGC 2451 is a very bright open cluster containing the star c Puppis, and the near NGC 2477 is a good target for small telescopes. The star Pi Puppis is the main component of a bright group of stars known as Collinder 135. M46 is a circular open cluster with an overall magnitude of 6.1 at a distance of approximately 5400 light-years from Earth. The planetary nebula NGC 2438 is superimposed; it is approximately 2900 light-years from Earth. M46 is classified as a Shapley class f and a Trumpler class III 2 m cluster. This means that it is a rich cluster that appears distinct from the star field. However, it is not at its center. The cluster's stars, numbering between 50 and 100, have a moderate range in brightness. See also Puppis (Chinese astronomy) References Sources Ian Ridpath and Wil Tirion (2017). Stars and Planets Guide, Collins, London. . Princeton University Press, Princeton. . Richard Hinckley Allen, Star Names, Their Lore and Legend, New York, Dover. External links The Deep Photographic Guide to the Constellations: Puppis The clickable Puppis Star Tales – Puppis Constellations Southern constellations Constellations listed by Lacaille