Exoplanet hunters Christopher Watson and Annelies Mortier explain the long search for a 'twin Earth' capable of sustaining life.

Mercury is tiny, barely bigger than the Moon. Its metallic core makes up 70% of the planet’s mass, vastly exceeding Earth’s 32% and Mars ’ 25%. It’s unlikely that the core actually formed like this.

A new study suggests yet another theory for a possible extra planet in our solar system, likely of a size between Mercury and Earth. The authors dubbed it Planet Y.

A recent theory has emerged suggesting that the answer to Mercury’s unusually large metallic core may lie in the early history of our solar system. This theory proposes that a soft collision between ...

Scientists have shown that Earth’s basic chemistry solidified within just three million years of the Solar System’s formation. Initially, the planet was barren and inhospitable, missing water and ...

On August 24, 2006, our solar system lost a planet. It wasn't by cataclysmic destruction, but rather by the vote of the International Astronomical Union, which declared that Pluto, considered the ...

On October 6 1995, at a scientific meeting in Florence, Italy, two Swiss astronomers made an announcement that would transform our understanding of the universe beyond our solar system. Michel Mayor ...

The timing of Earth's early formation points to a planet that started out dry. So, life’s essential building blocks arrived later, but how?

NASA has gone silent just hours before humans get their most detailed look at the mysterious object traveling through the solar system.

A respected Harvard astrophysicist believes one of the most famous signals ever sent to Earth could have been sent by the object rapidly approaching our planet.

NASA’s Parker Solar Probe has once again made history by achieving a speed that is almost unimaginable. During its recent journey through the Sun’s outer atmosphere, known as the corona, the ...