However, what constitutes a planet in particular is a question that may seem very simple but has been escalating in complexity as scientists discover new planets that defy the classical definition.

Astronomers have finally pinned down both the mass and distance of a solitary “rogue” planet, a world that drifts through space without the warmth or light of a parent star. The object, a Saturn-sized ...

Astronomers have observed a planet that in some ways behaves more like a star — including a massive growth spurt unlike anything witnessed before in a free-floating planet. The rogue planet, which ...

Peking University, January 2, 2026: A lucky alignment of space- and ground-based telescopes has enabled researchers to nail down the mass of a rogue planet for the first time. Unlike worlds in our ...