Nearly a century after Pluto’s discovery, astronomers are still hunting for mysterious planets beyond Neptune - including a ...

Might the solar system harbor not just one, but two unknown planets? A fresh study of the Kuiper Belt’s structure has revived ...

Most planet-forming disks have warps that can lead to planets on inclined orbits, which could explain where the tilt of Earth's orbit came from. The origin of the differing tilts in the orbits of the ...

Our solar system is a smashing success. A new study suggests that from its earliest period — even before the last of its nebular gas had been consumed — Earth’s solar system and its planets looked ...