Dark Nebulae / Emission Nebulae / Planetary Nebulae / Reflection Nebulae / Supernova Remnants
Diffuse Nebula M8 (NGC 6523), an emission nebula, in Sagittarius
Lagoon Nebula
Right Ascension 18 : 03.8 (h:m)Declination -24 : 23 (deg:m)
Distance 5.2 (kly)
Visual Brightness 6.0 (mag)
Apparent Dimension 90x40 (arc min)
Cluster NGC 6530 discovered by Flamsteed about 1680. Lagoon Nebula discovered by Le Gentil in 1747.
As often for diffuse nebulae, the cluster of young stars which has formed from the nebula's material was discovered first, in this case the young open cluster NGC 6530 in the Eastern half of M8 was discovered by Flamsteed about 1680, and again seen by De Chéseaux in 1746, before Le Gentil found the nebula in 1747. Abbe Nicholas Louis de la Caille has cataloged it in his 1751-52 compilation as Lacaille III.14. When Charles Messier cataloged this object on May 23, 1764, he also primarily described the cluster, and mentioned the nebula separately as surrounding the star 9 Sagittarii; his original position is closer to the modern position of the cluster than to that of the nebula. Nevertheless, it is the nebula which is now generally regarded as "Messier 8".
