The Orion Nebula will get some stiff competitors for greatest in school from the Lagoon Nebula (M8) in Sagittarius. The Lagoon Nebula is seen to the bare eye on darkish moonless nights as a brilliant patch alongside the Milky Way due north of the spout of the Sagittarius Teapot asterism.
The Lagoon Nebula was found by Italian astronomer Giovanni Battista Hodierna in 1654, when he described it as a nebulosa. What Hodierna seemingly noticed, nevertheless, will not be what we all know at this time because the Lagoon Nebula, however reasonably an embedded open star cluster cataloged individually as NGC 6523. In truth, most information of the early observations consult with the open cluster with out mentioning the nebula from which it was born.
William Herschel was the primary to outline the nebula as a separate object. In 1785, he described it as “an in depth milky nebulosity divided into two components.” Irish astronomer Agnes M. Clerke coined the nickname “the Lagoon Nebula” in her 1890 e-book The System of the Stars.
Once we set our sights on M8, our gaze is taking us some 4,100 light-years away. Beneath darkish skies, 10×50 binoculars can distinguish the Lagoon’s general oval form, in addition to the darkish slice that cuts the nebula in half. Telescopes, in the meantime, reveal a number of of the swirling nebula’s extra advanced options.
Hidden throughout the nebula is one other star cluster: NGC 6530. A few of its younger stars sparkle among the many rifts of nebulosity. For those who plan to hunt it out, anticipate to identify between two dozen and three dozen luminaries by way of most yard scopes.
Many different stars lie throughout the Lagoon’s clouds, too. One of many brightest is Sixth-magnitude 9 Sagittarii, a large binary system comprising two extraordinarily shut sort O stars whose radiation energizes a lot of the nebula. One other noteworthy star within the subject is Herschel 36, a magnitude 9.5 supergiant simply west of the brightest portion of the nebula.
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