Milky Way

The Milky Way (a translation of the Latin Via Lactea, in turn derived from the Greek Galaxia Kuklos) is the galaxy in which the Earth is found. When viewed from the Earth and its environs, it appears in the night sky as a hazy band of white light (hence "milky") across the celestial sphere, formed by stars within the disc of its namesake galaxy. It is also simply known as the Galaxy, as the Earth's solar system is a part of it. The Milky Way appears brightest in the direction of Sagittarius, where the galactic center lies.

Relative to the celestial equator, the Milky Way passes as far north as the constellation of Cassiopeia and as far south as the constellation of Crux. This reflects the fact that the Earth's equatorial plane is highly inclined to the galactic plane, as is the ecliptic (the plane in which the Earth and the other significant planets orbit the Sun). The fact that the Milky Way divides the night sky into two roughly equal hemispheres reflects the fact that the solar system lies close to the galactic plane.

To put the Milky Way into perspective, if you made it 130 km (80 mi) in diameter, our solar system would only be 2 mm (0.08 in) in diameter. Also, if a beam of light were to be shot around the Milky Way, it would take almost 250,000 years to complete its journey.

Catagory:Planets & Locations