Gaia, Europe’s Milky Way–mapping spacecraft, shut down earlier this year. It was arguably the most important—and most ...

Can the lead plaintiff in the gay marriage case move on from his grief — and can America move on from homophobia?

CHAPTER 7 Gertrude’s brother-in-law and sister strongly opposed the marriage because I was only a clerk. But she was ...

Majestic ancestral homes echoing with history and mystery, long vanished yet still stirring the imagination with their timeless stories.

We have discovered two interstellar objects so far, ’Oumuamua and Comet 2I/Borisov. ’Oumuamua had no dust tail and a ...

Everything in space—from Earth and the sun to black holes—accounts for just 15% of all matter in the universe. The rest of ...

Astronomers theorize it happens as gas is ejected from galaxies when massive stars explode in supernovas, or when supermassive black holes inside galaxies expel material after consuming stars or gas.

Astronomers have long estimated that ordinary matter – basically, anything other than dark matter – makes up only a fraction of the known universe.

Astronomers have long estimated that ordinary matter – basically, anything other than dark matter – makes up only a fraction of the known universe.

Stephen Schneider is a Professor of Astronomy at UMass Amherst. This article is republished from The Conversation under a Creative Commons license. Read the original article.

Astronomers theorize it happens as gas is ejected from galaxies when massive stars explode in supernovas, or when supermassive black holes inside galaxies expel material after consuming stars or gas.