The Universe

Close stellar encounters could change the structure of our planetary system, potentially dooming Earth or other worlds to oblivion

Spacecraft can get a significant boost by stealing energy from planets

A near-complete census of our interstellar neighborhood hopes to answer how stars, brown dwarfs and rogue planets form throughout the universe

A curious celestial phenomenon known as the analemma is a reflection of Earth’s orbit and tilted axis

Telescopes in space give us a view we literally cannot get from the ground

Some stars streaking through the Milky Way at millions of kilometers per hour probably trace back to a supermassive black hole in a neighboring galaxy

The quirks of light moving through gas are the cause of stellar twinkling, which can be a bane—and sometimes a boon—for astronomers

Galaxies come in many shapes and sizes, and trying to define them is difficult

Stars like the sun might erupt with extreme explosions about once per century

It seems contrary to common knowledge, but sound can travel through some parts of space quite well

ORCs—odd radio circles—are one of the weirdest recent discoveries in the heavens above

At the lower end, and to the bitter end, defining a star is tougher than you might expect