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

Most planetary systems contain worlds larger than Earth but smaller than Neptune, and the low-density planets around one ...

The discovery of an extraordinary multi-planet system has demonstrated that so-called "hot Jupiter" planets may not be lonely giants after all. The findings could force scientists to revise their ...

A four-planet system reveals remarkable insights about how planets form and how they change during their lifetime.

Now, a new Nature study points to an answer by catching four planets at a stage most systems never show us: The awkward, ...

The planets have been nicknamed Earth's seven sisters. — -- An international team of astronomers has discovered seven potentially habitable exoplanets — or planets outside our solar system — that ...

There have been questions about a mysterious ninth planet in our solar system for nearly a decade. Pluto was unseated as number nine in 2006. Now, a group of international researchers say they may ...

Planet Y is the latest in a series of hypothetical solar system planets that scientists have proposed in recent years, all with slightly different characteristics but collectively believed to be ...

Astronomers have captured an exceptionally rare view of young planets in mid-transformation, revealing how bloated, giant worlds may shrink into the most common planets in the galaxy. Astronomers have ...

What seemed like new planets around Fomalhaut were actually expanding dust clouds from violent planetary collisions seen by Hubble.

The search for an unknown planet in our solar system has inspired astronomers for more than a century. Now, a recent study suggests a potential new candidate, which the paper’s authors have dubbed ...