Mercury has long baffled astronomers because it defies much of what we know about planet formation. A new space mission ...

Discover why the solar system's planets are arranged as they are, shaped by formation conditions and planetary migration.

Astronomers using planet-hunting satellites have discovered a rare solar system with six planets moving completely in sync with one another, as if they were untouched by any outside force since being ...

When 'Oumuamua traversed our solar system in 2017 it was the first confirmed Interstellar Object (ISO) to do so. Then in 2019, Comet 2l/Borisov did the same thing. These are the only two confirmed ...

The International Astronomical Union (IAU) defines a planet as a celestial body orbiting the Sun, possessing sufficient mass for a nearly spherical shape, and having cleared its orbital neighborhood ...

For the inner four planets in this solar system, each planet orbits the sun three times for every two orbits of the planet immediately to its outside. For the fourth, fifth and sixth planets, they ...

Astronomers are closing in on one of the most tantalizing possibilities in planetary science, evidence that a previously ...

Jupiter currently shines as a brilliant silvery "star" in the constellation Gemini the Twins, low in the east-northeast sky ...

Astronomers have discovered a rare solar system with six planets moving in sync with one another. Estimated to be billions of years old, the formation 100 light-years away may help unravel some ...

The upcoming year will offer a blood-red moon, spectacular meteor showers and the first glimpse of the sun’s corona since ...

With sapphire waterfalls, lava rain and orbits around dead stars, these distant worlds push the limits of what’s possible.