Messier 73 [SEP] constellation
Messier 73
Messier 73 (M73, also known as NGC 6994) is an asterism of four stars in the constellation of Aquarius. An asterism is composed of physically unconnected stars that appear close to each other in the sky as seen from Earth.
History.
M73 was discovered by Charles Messier on October 4, 1780, who originally described the object as a cluster of four stars with some nebulosity. Subsequent observations by John Herschel, however, failed to reveal any nebulosity. Moreover, Herschel noted that the designation
Messier 9
Messier 9 or M9 (also designated NGC 6333) is a globular cluster in the constellation of Ophiuchus. It is positioned in the southern part of the constellation to the southwest of Eta Ophiuchi, and lies atop a dark cloud of dust designated Barnard 64. The cluster was discovered by French astronomer Charles Messier on June 3, 1764, who described it as a "nebula without stars". In 1783, English astronomer William Herschel was able to use his reflector to resolve individual stars within the cluster. He