A planet-size object that possibly once visited the solar system may have permanently changed our cosmic neighborhood by ...

Artist's impression of Planet Nine – a suspected “wide-orbit” planet – with the Sun in the distance; Neptune's orbit is shown ...

A NASA Hubble Space Telescope observation program called OPAL (Outer Planet Atmospheres Legacy) obtains long-term baseline observations of Jupiter, Saturn, Uranus, and Neptune in order to ...

Part of its yearly grand tour of the outer solar system, NASA’s Hubble Space Telescope captured new technicolor images of the giant planets: Jupiter, Saturn, Uranus, and Neptune. The collection ...

Using computer models of the four outer planets, the team carried out 50,000 simulations of such flybys, each over 20 million years, while altering certain parameters of each visitor, ...

Using computer models of the four outer planets, the team carried out 50,000 simulations of such flybys, each over 20 million years, while altering certain parameters of each visitor, including ...