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Constellations An apparent group of stars originally named for mythical characters.
Parallax The slight shifting in apparent position of a nearby star due to the orbital motion of Earth.
Light-Year The distance light travels in one year.
Apparent Magnitude A star's brightness as it appears from Earth.
Absolute Magnitude How bright a star actually is.
Main-Sequence Star A star that falls into the main-sequence category on the H-R diagram.
Red Giants A large, cool star of high luminosity
Super giant A very large, very bright red giant star
Cepheid Variables A star whose brightness varies periodically because it expands and contracts (pulsating).
Nebulae Clouds of gas and dust in space
Protostar A developing star not yet hot enough to engage in nuclear fusion.
Supernova An exploding star that increases in brightness many thousands of times
White Dwarf A star that has exhausted most or all of its nuclear fuel and has collapsed to a very small size.
Neutron Stars Stars that are smaller and more massive than white dwarfs, thought to be the remnants of supernova events.
Pulsar A spinning neutron star that appears to give off pulses of radio waves.
Black Hole Dense objects with gravity so strong that not even light can escape the surface.
Spiral Galaxies Disk-shaped galaxies with a greater concentration of stars near their nuclei.
Elliptical Galaxies Galaxies that range in shape from round to oval.
Irregular Galaxies Galaxies with irregular shapes.
Galaxy Clusters Galaxies that are grouped together.
Created by: ksingleton
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