A rare comet from another star system is revealing just how different alien solar systems may be from our own.

The presence of deuterium, an isotope of hydrogen, in 3I/ATLAS suggests the interstellar comet formed in a much colder place ...

Measurements of this interstellar comet’s molecular makeup show an excess of heavy water molecules that is dramatically different from anything known to have ever formed around our sun ...

Even at a glance, the planets in our solar system are wildly diverse. Huge and small, airless and densely packed with ...

Astronomers have spotted something surprising in the far outer Solar System—a faint, short-lived atmosphere clinging to a ...

And the earth was without form and void, and darkness was upon the face of the deep. Sometimes, if the night is dark and clear enough, you can look up and see the Milky Way in its arc across the sky.

Approximately 4.5 billion years ago, a cold cloud of gas and dust buried deep in one of the Milky Way galaxy’s spiral arms started to collapse. From there, gravity worked its magic. The cloud began to ...