Possibly discovered by G.D. Cassini 1711.
Discovered independently by Charles Messier on April 5, 1772.
[Mem. Acad., 1777, p. 345-359, on the comet of 1772 (Messier's 13th,
discovered by Montaigne, actually comet 3D/Biela); here p. 349]
[April 5, 1772] I determined, in the same evening, the position of a cluster
of small starsplaced between the star Theta in the earof Canis Major, &
the right loins of Monoceros; I compared this cluster with the telescopic
star, determined on April 3, & this one with a star of the seventh
magnitude which was near the cluster. The positions are reported in the
second table.
[p. 351]
RA: 102.57.28, Dec: 7.57.41.A. Star cluster.
[The position of M50 is given in the chart on Pl. VI, facing p. 352]
Sweep 135 (March 13, 1828)
RA 6h 54m 45.5s, NPD 98d 6' 55" (1830.0)
A L rather straggling cl 10..12' diam; st 11....15 m. The largest in M,
taken.
A large rather straggling cluster, 10 to 12' diameter; stars of 11th to 15th
magnitude. The largest in the middle, taken [for position measurement].
Sweep 318 (January 8, 1831)
RA 6h 54m 46.6s, NPD 98d 6' 58" (1830.0)
Superb cl; fills whole field; irreg R; stars 11...15 m; not comp in M;
straggling stars extend over a circle 30' in diameter.
Superb cluster; fills whole field; irregularly round; stars of 11th to 15th
magnitude; not compressed in the middle; straggling stars extend over a
circle 30' in diameter.
Sweep 136 (March 14, 1828)
RA 6h 54m 49.4s, NPD 98d 6' 2" (1830.0)
A fine v L sc cl; has a red star 8.9 m to s of the more compressed part.
A fine very large scattered cluster; has a red star of 8 or 9 mag to south
of the more compressed part.
Last Modification: March 29, 2005