Picture a star, about half the sun’s mass shining with a dim red light. Lumbering around it on a 5,000-year orbit is a huge ...

The object orbits a brown dwarf that orbits a star, and astronomers aren’t sure if it’s a planet, a moon — or something else entirely.

A 24-year-old observatory assistant from the Midwest discovered Pluto. Clyde Tombaugh, born in 1906 in Streator, Illinois, ...

Pluto lost its planethood for a very specific reason. Whether or not that’s a good reason depends on who you ask.

Discovered in 1930, Pluto reigned as the ninth planet for 76 years — now, 20 years after its demotion, the debate still rages ...

M onday, August 24 marks the 20th anniversary of the International Astronomical Union (IAU) vote to adopt a formal definition ...

In a groundbreaking discovery, astronomers have identified a potential dwarf planet candidate, 2017 OF201, buried within ...

For centuries, humans have gazed at the stars, trying to understand what lies beyond the familiar planets we know. From Mercury’s blazing orbit near the Sun to Neptune’s icy edge, our Solar System has ...

Astronomers using NASA’s James Webb Space Telescope have uncovered a rare world unlike anything in our solar system — a giant planet about the size of Saturn with surprisingly Earth-like temperatures ...

As the likely next step for humankind's space exploration, Mars has fascinated us for quite a while now. Humans have found many strange things on Mars while studying the planet, and there's even some ...

Rachel Feltman: Happy Monday, listeners! For Scientific American’s Science Quickly, I’m Rachel Feltman. Let’s kick off the week with a quick roundup of some of the latest news. First, let’s talk about ...

On the steps of the U.S. Capitol on a balmy October morning, a crowd of people sporting “Save NASA Science” buttons buzzes with anticipation. Among them stands Eli Orland, who likens America’s space ...