The Milky Way, sometimes called simply the Galaxy, is the galaxy in which our Solar System is located. It is a barred spiral galaxy that is part of the Local Group of galaxies. It is one of billions of galaxies in the observable universe.
Its name is a translation of the Latin Via Lactea, which derives from the Greek Γαλαξίας (Galaxias or Galaxiases), both of which refer to the pale band of light formed by the galactic plane as seen from Earth (see etymology of galaxy). Some sources hold that, strictly speaking, the term Milky Way should refer exclusively to the band of light that the galaxy forms in the night sky, while the galaxy as an astrophysical whole should receive the full name Milky Way Galaxy, or alternatively the Galaxy. However, it is unclear how widespread this convention is, and the term Milky Way is routinely used in either context.
Its name is a translation of the Latin Via Lactea, which derives from the Greek Γαλαξίας (Galaxias or Galaxiases), both of which refer to the pale band of light formed by the galactic plane as seen from Earth (see etymology of galaxy). Some sources hold that, strictly speaking, the term Milky Way should refer exclusively to the band of light that the galaxy forms in the night sky, while the galaxy as an astrophysical whole should receive the full name Milky Way Galaxy, or alternatively the Galaxy. However, it is unclear how widespread this convention is, and the term Milky Way is routinely used in either context.
Appearance from Earth:
The Milky Way galaxy, as viewed from Earth, itself situated on one of the spiral arms of the galaxy (see Sun's location), appears as a hazy band of white light in the night sky arching across the entire celestial sphere and originating from stars and other material that lie within the galactic plane. The plane of the Milky Way is inclined by about 60° to the ecliptic (the plane of the Earth's orbit), with the North Galactic Pole situated at right ascension 12h 49m, declination +27.4° (B1950) near beta Comae Berenices. The South Galactic Pole is near alpha Sculptoris.The Milky Way looks brightest in the direction of the constellation of Sagittarius, toward the galactic center. Relative to the celestial equator, it passes as far north as the constellation of Cassiopeia and as far south as the constellation of Crux, indicating the high inclination of Earth's equatorial plane and the plane of the ecliptic relative to the galactic plane. The fact that the Milky Way divides the night sky into two roughly equal hemispheres indicates that our Solar System lies close to the galactic plane. The Milky Way has a relatively low surface brightness, making it difficult to see from any urban or suburban loc
ation suffering from light pollution.
ation suffering from light pollution.The Milky Way as seen from Death Valley, 2007. This is a panoramic picture.
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