*Nebula(plural nebulae) was the word once used for any fuzzy patch of light in the night sky. Nowadays, many nebulae are known to be galaxies instead.
*Many nebulae are gigantic clouds of gas and space dust.
*Growing nebulae are named because they give off a dim, red light, as the hydrogen gas in them is heated by radiation from nearby stars.
*The Great Nebula of Orion is a glowing nebula just visible to the naked eye.
*Reflection nebulae have no light of their own. They can only be seen because starlight shines off the dust in them.
*Dark nebulae not only have no light of their own, they also soak up all light. The can only be seen as patches of blackness, blocking out light behind them.
*The Horsehead nebula in Orion is the best-known dark nebula. As its name suggests, it is shaped like a horse's head.
*Planetary nebulae are thin rings of gas cloud which are thrown out by dying stars. Despite their name, they have nothing to do with planets.
*The Ring nebula in Lyra is the best-known of the planetary nebulae.
*The Crab nebula is the remains of a supernova that exploded in AD 1054.
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1000 Things You Should Know About Space
Non-FictionWhat is written here are facts and about true reasearch of SPACE
