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Stellar Astrophysics
2014-01-12 00:00:00

The prominent feature that allows for the existence of life on Earth is the Sun. Radiation from our closest star provides heat and energy to our planet, driving biological processes and providing the necessary conditions for liquid water to naturally exist. But our Sun is only but one star in this vast Universe. And as it turns out, most stars are quite different than the one that...

2004-10-19 04:45:42

Supernova -- A supernova is a star that increases its brightness drastically within a matter of days, making it appear as if a "new" star was born (hence "nova"). The "super" prefix distinguishes it from a mere nova, which also involves a star increasing in brightness, though to a lesser extent and through a much different mechanism. Astronomers have classified supernovae in several...

The Sun
2004-10-19 04:45:40

The Sun -- intensely hot, self-luminous body of gases at the center of the solar system. Its gravitational attraction maintains the planets, comets, and other bodies of the solar system in their orbits. The sun is actually a star of about medium size; it appears larger than the other stars because of its relative nearness to the earth. The earth's distance from the sun varies from 91,377,000...

Crab Nebula
2004-10-19 04:45:40

Crab Nebula -- The Crab Nebula (Messier 1, NGC 1952) is the object the which started Charles Messier logging non-cometary objects on his Messier Catalog. It is the expanding cloud of gas thrown off in the explosion that gave rise to the 1054 supernova recorded by Chinese astronomers, now more than 6 light years across (the nebula is currently expanding at 1000 km/sec and the total mass of...

Word of the Day
  • Sleep; the state or condition of being asleep.
  • The state or condition of numbness of a part due to pressure on a nerve: as, the obdormition of a limb.
The word 'obdormition' comes from a Latin word meaning "to fall asleep".