The Conversation

Why do astronomers believe in dark matter?

Author: Michael J. I. Brown, Associate professor in astronomy, Monash University

The universe is home to a dizzying number of stars and planets. But the vast bulk of the universe is thought to be invisible dark matter.Illustris Collaboration, CC BY-NC

Dark matter, by its very nature, is unseen. We cannot observe it with telescopes, and nor have particle physicists had any luck detecting it via experiments.

So why do I and...

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