dark matter
MYSTERIOUS NON-LUMINOUS MATTER (AND/OR RADIATION) COMPRISING MOST OF THE MATTER IN OUR OBSERVABLE UNIVERSE
Dark matter problem; Missing mass problem; Missing mass; Dark Matter; Dark matter in fiction; Dark matter (fiction); Dark gravity; Black matter; Darkmatter; Dark matter behavior; Nonbaryonic dark matter; Dark matter theory; Dark-matter; Dunkle materie; Dark attractive force theory; Distribution of dark matter
Dark matter is material that is believed to form a large part of the universe, but which has never been seen.
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