Dark matter is composed of particles that do not absorb, reflect, or emit light, so they cannot be detected by observing electromagnetic radiation. Dark matter is material that cannot be seen directly.
Unlike normal matter, dark matter does not interact with the electromagnetic force. This means it does not absorb, reflect or emit light, making it extremely hard to spot. In fact, researchers have been able to infer the existence of dark matter only from the gravitational effect it seems to have on visible matter.
Dark matter makes up over 80% of all matter in the universe, but scientists have never seen it. We only assume it exists because, without it, the behavior of stars, planets and galaxies simply wouldn’t make sense.
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