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Star Systems and Galaxies
a star system with two stars
a binary star system in which one star periodically blocks the light from the other
a star cluster that has a loose, disorganized appearance and contains no more than a few thousands
a large, round, densely-packed grouping of older stars
a huge group of single stars, star systems, star clusters, dust, and gas bound together by gravity
a galaxy with a bulge in the middle and arms that spiral outward in a pinwheel pattern
a galaxy shaped like a round or flattened ball, generally containing only old stars
a galaxy that does not have a regular shape
an enormously bright, distant galaxy with a giant black hole at its center
all of space and everything in it
a mathematical method of writing numbers using powers of ten