If Planet 9 exists, it may have been stolen from another star system.

The mysterious planet may glow like a jellyfish.

Mike shows the space telescope some tough love in order to make vital repairs.

Flowing liquid nitrogen smoothed the vast plain known as Sputnik Planum.

Charon is the strangest of Pluto’s very strange moons.

A collapsed star orbiting a pulsar has become a giant diamond.

Planet TrES-2b is so hot that its atmosphere absorbs virtually all the light from its star.

Was the moon a captured planet?

Unexplained observations suggest the Moon is alive.

Einstein's theory of general relativity was not always considered correct. It wasn't until Hubble made a grand discovery that the equation was fixed.... or was it? Some scientists believe the equation should actually go back to it's original form due to dark energy.

The solar system is more geologically active than you might think.

Jupiter’s red eye has been swirling for at least 350 years.

Dark energy is an unknown form of energy which is hypothesized to permeate all of space, tending to accelerate the expansion of the universe.

Luckily the Cassini spacecraft was there to witness one of these storms.

Evidence suggests that the so called "habitable zone" changes as the Sun ages. Many years ago, Venus may have resembled Earth and been home to life.

Volcanic activity on Io, one of Jupiter’s moons, could be the key to the planet’s extraordinary auroras. Here’s how scientists at Syracuse University in New York have recreated volcanic activity on Io.