Astronomers are closing in on one of the most tantalizing possibilities in planetary science, evidence that a previously unknown world may be lurking in the outer reaches of the solar system. The ...

Theorbits of Jupiter, Saturn, Uranus and Neptune may have been altered by the fly-by of an enormous object from deep space, billions of years ago. According to a pre-print research paper, which is yet ...

A massive interstellar object passing through our solar system during its formative years likely altered the orbits of planets into trajectories observed today, a new study says. Interactions with ...

The Sun is an incandescent but benevolent dictator. For billions of years, it’s kept our star system well organized through the influence of its powerful gravity. All the planets revolve around it on ...

Scientists have been trying to find a hypothetical Planet 9 that may exist outside our known solar system based on the unusual orbits of certain dwarf planets. But those orbits might not require a ...

Add Yahoo as a preferred source to see more of our stories on Google. Jupiter is already the biggest planet by far in our solar system, but new research suggests it was somehow once even larger than ...

From meteorites that impact Earth, to a moon that orbits backwards... From meteorites that impact Earth, to a moon that orbits backwards, to an imposter lurking in the asteroid belt, a variety of ...

The Subaru Telescope has made an exciting discovery: a small body beyond Pluto, with implications for the formation, evolution, and current structure of the outer solar system. The object was found as ...