The number of planets that orbit the sun depends on what you mean by “planet,” and that’s not so easy to define ...

Filmmaker Adam Nemoy helps celebrate the 90th anniversary of Pluto's discovery this month at the 6th annual 'I Heart Pluto' ...

If planets had social media accounts, the solar system would showcase a frenzy of unique personalities. Mercury tweets at ...

According to a recent YouGov poll, 35% of Americans think Pluto is not a planet. But they are all wrong—kind of. To get to ...

And its relationship to Pluto — a world demoted since 2006 from the solar system’s ninth planet to a lowly dwarf planet, in large part due to the discovery of Eris — remains contentious today.

This provides another piece of the puzzle to understand how planets and ... Pluto-Charon Formation Scenario ... a clearer picture of how the outer solar system formed and evolved based on analyses ...

NASA’s New Horizons mission changed our understanding of the outer solar system. After its famous Pluto flyby, it traveled ...

If it’s real, some may question whether something with a mass about three times Pluto’s counts as a planet at all.

However, this year a powerful new telescope is coming online that could prove once and for all that there really is a ninth planet in our Solar System. The same year that Pluto was ignominiously ...

High winds, hundreds of lightyears away! Dan Smith shows just how fast one planet's jet stream is moving. 🪐💨 ...