If not in visible stars and galaxies, the most likely hiding place for the matter is in the dark space between galaxies.

The universe is full of wonders, but some worlds are downright deadly. From searing heat to violent storms, these planets make Earth look like a paradise. Many of them challenge everything we know ...

Calculating the total mass of the universe is not simple, because most of the mass is invisible. In a pie chart of the contents of the universe, only 5 percent is normal matter, atoms that make up all ...

Rocky planets like our Earth may be far more common than previously thought, according to new research published in the ...

(The Conversation is an independent and nonprofit source of news, analysis and commentary from academic experts.) Chris Impey, University of Arizona (THE CONVERSATION) If you look across space with a ...

Chris Impey has received funding from NASA, NSF, Howard Hughes Medical Institute, and the Templeton Foundation. If you look across space with a telescope, you’ll see countless galaxies, most of which ...