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

Nasa's powerful James Webb Space Telescope is showing us something humankind has never witnessed firsthand before: The birth ...

Add Yahoo as a preferred source to see more of our stories on Google. Are planets in the solar system that are closer to the Sun older than the ones further away? – Gavriel, age 10, Paducah, Kentucky ...

For decades, we believed our Solar System ended with Neptune, followed only by icy debris and distant dwarf planets. But ...

Illustration comparing the planets of the Solar System and the Sun on the same scale. The planets are shown to scale relative to each other but their distances are not. From left to right the bodies ...

Because the planets in our solar system are so bright, they flood the telescope's sensors with more light than they can ...

The giant planets weren't always where we find them today. Jupiter, Saturn, Uranus and Neptune formed in a more compact configuration and later underwent a violent reshuffling that scattered them to ...

Astronomers have discovered the earliest seeds of rocky planets forming in the gas around a baby sun-like star, providing a precious peek into the dawn of our own solar system. It's an unprecedented ...

A distant 'exomoon' the size of Jupiter is changing how we think about the cosmos.

Even at a glance, the planets in our solar system are wildly diverse. Huge and small, airless and densely packed with atmosphere, they have a wide range of characteristics distinguishing them. But if ...