A new study has proposed the existence of Planet Y, an alternative Planet Nine candidate that is smaller and closer to Earth ...

There are a couple of ways that scientists can date planets, so which planets formed first in our solar system?

Long before continents, oceans, or life Earth was a molten inferno. The Hadean Eon (4.6 to 4.0 billion years ago) was a time ...

A low-density, puffy planet orbiting relatively far from a young star in a nearly perpendicular orbit. What's going on?

All the planets orbit in roughly the same plane because they formed from a single rotating disk of gas and dust — the solar nebula — that flattened as it spun around the young Sun. The shared origin ...

Astronomers have discovered seeds of rocky planets forming in the gas around the baby sunlike star providing *** peek into the start of our own solar system. The the thing that we've discovered is ...

NEW YORK (AP) — Six planets are hanging out in the sky this month in what’s known as a planetary parade. Catch the spectacle while you can because it’s the last one of the year. These linkups happen ...