Lagoon Nebula is the name of a bright, diffuse nebula in the southern constellation Sagittarius; cataloged as M8 or NGC 6526. It is visible to the naked eye and has an angular area larger than that of the full moon.
The Lagoon Nebula in Sagittarius is a cradle of stars being newly born from dust clouds; we are the stuff of those stars.
Lagoon Nebula is the name of a bright, diffuse nebula in the southern constellation Sagittarius; cataloged as M8 or NGC 6526. It is visible to the naked eye and has an angular area larger than that of the full moon.
The central parts are extremely bright, and some stars can be seen embedded in the nebulosity. Because of the nebula's large size, light from its stars cannot illuminate all of the associated interstellar gas and dust. Thus, parts of it appear blacker than the surrounding sky. The constellation Sagittarius contains a configuration of stars known as the Milk Dipper. It also contains the Lagoon, Horseshoe, and Trifid nebulae (nebulas).
The center of our galaxy, the Milky Way , lies in Sagittarius.
The Columbia Encyclopedia, Sixth Edition | Date: 2008
Sirius in the constellation Canis major is also known as the star of Isis, the Egyptian deity who put her brother, lover, husband Osiris back together making him whole.
As Sirius is 8.7 light years distant, it is not the closest star system - the Alpha Centauri system holds this distinction. Sirius is called the Dog Star because of its prominence in the constellation of Canis Majoris (Big Dog). Based on changes in its proper motion, in 1844 Friedrich Wilhelm Bessel deduced that Sirius had a hidden companion. In 1862, Sirius was discovered to be a binary star system with a (twin) companion star, Sirius B, 10,000 times dimmer than the bright primary, Sirius A. Sirius B was the first white dwarf star discovered, a type of star first understood by Subrahmanyan Chandrasekhar in 1930.
By orbiting directly towards us, Sirius creates an axis of rotation with Earth relative to the stellar background. Because of this, of all the stars in the sky, only the annual heliacal rising of Sirius exactly matches the length of our solar year, 365.25 days.
Canis Major, the Greater Dog is visible in the Northern Hemisphere from December - March, and visible in the Southern Hemisphere between November and April.
Canis Major has since ancient times been the dog of Orion. Canis is forever in pursuit of the Hare (Lepus). The belt stars in Orion point to Sirius (the Dog Star), which we draw as the nose of the dog. The Egyptians saw the star rising as the season of flooding on the Nile began.
Here the earth is viewed as the center of the universe, something we have been denying since Galileo suggested otherwise, and we see the constellations of the zodiac as the wide band, outer-most circle in the page above from a book on Ptolemy's Almagest.
