Alone in a Crowded Milky Way
Even a galaxy teeming with star-hopping alien civilizations should still harbor isolated, unvisited worlds—and Earth might be among them
Stories by Caleb Scharf
Guess the Rain's down on Titan
Archival Cassini images reveal a glinting surface and a seasonal property
A Fantastic Journey through Cosmic Scales
A new, epic voyage through all known scales of reality charts the outer limits of existence, from the edge of the observable universe to the subatomic realm
Eclipse: It's All about the Umbra
What makes a total solar eclipse seem so strange and awe-inspiring?
Astronomers Measure How Fast a Supermassive Black Hole Is Spinning
To do so, they looked to a second black hole orbiting the first
Cassini Reveals That Enceladus Is Embraced by a Web of Cracks
The Cassini mission's third-from-last flyby of the icy moon Enceladus reveals that a highly complex network of thin cracks covering the surface extend all the way into the northern polar region...
Is Earth's Life Unique in the Universe?
To know whether life exists beyond Earth, we must come to terms with our own significance in the universe. Are we uniquely special or merely mediocre?
How Black Holes Shape the Galaxies, Stars and Planets around Them
The matter-eating beast at the center of the Milky Way may actually account for Earth's existence and habitability
How to find a habitable exoplanet: Don't look for one
Most planetary scientists will tell you that the objects they study are more complex and harder to categorize than almost anything else out there in the universe.
