New models suggest Uranus and Neptune may hold far more rock than expected, raising questions about how these distant planets formed.

The Gravity Assist Podcast is hosted by NASA's Director of Planetary Science, Jim Green, who each week talks to some of the greatest planetary scientists on the planet, giving a guided tour through ...

James is a published author with multiple pop-history and science books to his name. He specializes in history, space, strange science, and anything out of the ordinary.View full profile James is a ...

Far beyond the bright planets, in the dim outskirts of the Solar System, astronomers keep stumbling on objects that refuse to follow the rules. Around Neptune in particular, a handful of newly charted ...

You probably already know that gravity can greatly influence cosmic objects as they make their way through space. We see this constantly in how the Sun's gravity causes planets to orbit it. And even ...

The gravity of a planet, its star, and the centrifugal force associated with the planetary orbit nearly balance in five regions near the planet’s path where an asteroid (or spacecraft) could orbit ...

Inscrutable ice giants Neptune and Uranus have only a thin rind of windy weather over their fluid contents, a team of planetary scientists say. The research published in the journal Nature relies on ...