Pluto

Scientists say the Iowa-sized object in the asteroid belt has a surface composition similar to Ceres.

The findings could have implications for our understanding of how subsurface oceans form on other worlds.

The planet was discovered more than a decade ago in the outer reaches of the solar system.

"This is the most distant exploration of any world in history," Alan Stern said. "We are the Lewis and Clark of our era."

In 2006, the International Astronomical Union voted to downgrade Pluto to the status of dwarf planet, sparking a highly controversial debate that has yet to truly subside.

Some researchers think that a hypothetical ninth planet exists in the furthest reaches of the Solar System.

Scott Sheppard's team is using a supercomputer to simulate 79 discovered moons of Jupiter over billions of years to learn how often Valetudo would collide with its neighbors.

"We knew that every solar system body with an atmosphere and a solid rocky surface has dunes on it, but we didn't know what we'd find on Pluto."

Some of the most stunning photos of the planets and moons in our solar system, including our own.

Scientists have a new theory, called the cosmochemical model of Pluto formation.

To the disbelief of spectators, all of the animals which entered into the gates perished, while miraculously, the priests emerged unscathed.

The finding means we may need to add places like Pluto and Eris to our list of potentially habitable destinations.

It's not just because the sun is so far away.

Want to get away? Far, far away? Google now has you covered.

They're not just fields of ice spikes as tall as skyscrapers—they can also tell us about Pluto's past.

Don't cry too much about Cassini. Upcoming missions are going to Mars, Mercury, the Sun, Europa and several asteroids.

NASA is slowly releasing details about its visit to a Kuiper Belt Object four billion miles away.

The video shows Pluto's 2-mile high mountains and icy surface, as revealed in NASA's 2015 mission.

High-resolution photos from NASA's New Horizons spacecraft and other data show a complex, geologically active world.

NASA's Dawn spacecraft spent several weeks mapping Ceres from 900 miles up. Here's a simulated tour.

The planet is believed to be 5,000 times the mass of Pluto.

2015 will perhaps be remembered as a year of cultural tipping points.

Just three months after the historic flyby, the New Horizons team has a paper coming out in the journal "Science."

Program scientist Curt Niebur explains new data from NASA's New Horizons mission.

NASA has released an image taken by the New Horizons spacecraft just 15 minutes after its Pluto flyby.

Continuing a long tradition of space program conspiracy theories, 'Pluto Truthers' claim NASA is faking it.

A group of people sees the New Horizons as just the latest phony space mission.

One day after the flyby, the New Horizons team makes an important discovery about geology based on a detailed surface image.

The spacecraft's team waited anxiously for it to "let us know it's OK."

Videos, tweets and a Google doodle honor the historic moment in space exploration.