Every planet keeps time differently as it moves around the Sun. From Mercury’s 88-day year to Neptune’s 165-year orbit, this cosmic comparison shows how distance, speed, and gravity shape time across ...

Astronomers have long been puzzled by a cosmic mystery: planets orbiting two stars—like Star Wars’ Tatooine—are surprisingly rare, even though they should be common. New research suggests the culprit ...

This is a brilliant question because the notion of an orbit is counterintuitive. We know that massive objects (really, any objects with mass) gravitationally attract other massive objects; Newton's ...

Thanks to the discovery of thousands of exoplanets to date, we know that planets bigger than Earth but smaller than Neptune orbit most stars. Oddly, our sun lacks such a planet. That's been a source ...

Thanks to the discovery of thousands of exoplanets to date, we know that planets bigger than Earth but smaller than Neptune orbit most stars. Oddly, our sun lacks such a planet. That’s been a source ...

A giant planet two to four times the mass of Jupiter has been hiding in one of the most studied star systems in astronomy.

A Jupiter-size exoplanet orbiting a dead star baffled astronomers. But the planet named WD 1856 b could preview the fate of our own solar system when the sun dies.