The universe's missing matter may have finally been found. Astronomers think regular matter — that is, the stuff that isn't dark matter — makes up about 15% of the universe's total mass. However, for ...

Astronomers tallying up all the normal matter—stars, galaxies and gas—in the universe today have come up embarrassingly short of the total matter produced in the Big Bang 13.6 billion years ago. In ...

Astrophotographer Miguel Claro captured a stunning view of the Lion Nebula in the Cepehus constellation, revealing colorful clouds of ionized hydrogen gas. When you purchase through links on our site, ...

About half of the non-dark matter in the universe cannot be accounted for by stars and galaxies alone. Now, scientists say previously undetected clouds of hydrogen gas could finally reveal it. When ...