Mark your calendars for the last week of February, because one of the coolest celestial events is coming up where six planets will be visible in the night sky at the same time. This phenomenon, known ...

Scientists have identified a rocky outer planet in a system where a gas giant was expected. The discovery challenges ...

The similarities are astonishing. And yet... The post NASA Telescope Discovers Nearby Planet With Deep Similarities to Earth ...

Add Yahoo as a preferred source to see more of our stories on Google. Digital art of distant planet - Dottedhippo/Getty Images On August 24, 2006, our solar system lost a planet. It wasn't by ...

A newly identified planet candidate, HD 137010 b, looks strikingly Earth-like in size and orbit — but it may be colder than Mars due to its dimmer star. If it has a thick enough atmosphere, though, ...

Here's what to know about the brief tenure of our solar system's smallest planet.

Astronomers have uncovered a distant planetary system that flips a long-standing rule of planet formation on its head. Around the small red dwarf star LHS 1903, scientists expected to find rocky ...

Forbes contributors publish independent expert analyses and insights. Monica is an entertainment reporter covering TV, film, and music. “Set several generations in the future following Caesar’s reign, ...