M 8 The Lagoon Nebula

The Lagoon Nebula (also known as M 8, or NGC 6523) is a diffuse nebula in the constellation Sagittarius. it was discovered by Le Gentil in 1747.

It is one of the brightest H II regions in the sky and is visible even to the naked eye under fairly clear and dark skies. The Lagoon Nebula is easily spotted even with the naked eye on particularly clear nights; its location is easy to find, being about 7° north of the star γ Sagittarii (Al Nasl), which represents the arrowhead of Sagittarius. The region that hosts it is very rich in background stars and the glow of the Milky Way is very intense, due to the proximity of the core; A pair of 10x50 binoculars is able to show several details: it appears as an extensive and opaque spot, somewhat elongated in an east-west direction and surrounded by several stars. A 120-140mm telescope allows you to notice further details, such as variations in brightness intensity, and also several of the associated stars; With 200mm instruments, a large number of minor details are visible.

The Lagoon Nebula can be observed fairly easily from most of the populated areas of the Earth, thanks to the fact that it is located at a declination that is not excessively southern: in some areas of Northern Europe and Canada, near the Arctic Circle, its visibility is still impossible, while in central Europe it appears very low; from the southern hemisphere the nebula is clearly visible high in the nights of the austral winter and at the height of the Tropic of Capricorn it can be seen almost perfectly at the zenith. The best time to observe it in the evening sky is between June and October.

The nebula is located at a short distance from the ecliptic (less than one degree) and therefore cases of occultation by the various bodies of the solar system are not uncommon.