Which way is ‘down’ has a different answer depending on where you are on Earth, in the solar system, in our galaxy and beyond ...

Pluto's days, though they drag on a bit at around 153 hours, are nothing compared to its years. Pluto's orbit takes 248 Earth ...

In a real-life twist on Star Wars' Tatooine—a harsh desert planet with twin suns and a criminal underbelly—astronomers have found a bizarre new world that orbits two stars at a perfect right angle.

A planet circling at a sharp 90-degree angle to the orbits of its two host stars has now been confirmed. This discovery challenges long-standing ideas about how planets form and orbit in the cosmos.

The star system V1298 Tau reveals that many planets begin as large, low-density worlds that slowly shrink and shed their ...