Since the formation of the Solar System, the orbits of the planets have evolved and changed over time. While one of the most prominent ideas in the last few decades is planetary migrations and the ...

But once upon a time, billions of years ago, a massive object could have passed closely enough to gravitationally stir up the orbits of objects in the outer Solar System, causing the peculiar orbits.

Most planet-forming disks have warps that can lead to planets on inclined orbits, which could explain where the tilt of Earth ...

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 ...

Scientists may have found evidence of a ninth planet hiding out beyond Pluto, but is it actually Planet Nine?

For years, astronomers have been searching for a mysterious ninth planet lurking in the dark outer reaches of our solar system. Now, a team of researchers have taken a completely different ...