Thanks to new data from the New Horizons mission that shows how Pluto behaves as both a planet and a comet, it may be necessary to reclassify this world again!

A new image from Cassini shows Saturn's southern polar vortex in striking detail.

When you remove all the touch-ups and filters, the planets of the Solar System look slightly different than you might imagine, especially in terms of color

No one had a better view of the transit of Mercury across the Sun than the space-based Solar Dynamics Observatory, as it had a completely unobstructed view of the entire seven-and-a-half-hour event.

The airborne observatory SOFIA has detected atomic oxygen in Mars' upper atmosphere. It's been 40 years since oxygen has been detected there.

The SpaceX Falcon 9 first stage booster that successfully launched a Japanese satellite to a Geostationary Transfer Orbit (GTO) just 3 days ago and then nailed a safe middle of the night touchdown on a drone ship at sea minutes minutes later, is headed back to port and may arrive overnight or soon thereafter.

It's going to be almost impossible to travel to another star, but a new idea was announced that might get us to a nearby star within our lifetime. How will it work?

In billions of years, the Sun will enter its "Red Giant" phase and expand considerably. So naturally, we have to ask, will the Earth survive?

The long-awaited Falcon Heavy from SpaceX may make its inaugural launch in November, 2016. But what will its payload be?

Located in the Hercules constellation is M13, a globular cluster so large and bright that its nicknamed the "Great Hercules Cluster"

Amazing reader images of today's transit of Mercury across the face of the Sun from around the world.

A review of last night's spectacular aurora along with a look at tonight's space weather forecast plus a recap of tomorrow's big event - the transit of Mercury.

NASA GODDARD SPACE FLIGHT CENTER, MD - It's Mesmerizing ! That's the overwhelming feeling expressed among the fortunate few setting their own eyeballs on the newly exposed golden primary mirror at the heart of NASA's mammoth James Webb Space Telescope (JWST) - a sentiment shared by the team building the one-of-its-kind observatory and myself during a visit this week by Universe Today.

In the northern skies lies the constellation Auriga, one of the 44 described by Ptolemy and one of the 88 constellations recognized today by the IAU

The planet Mars has a highly eccentric orbit around the Sun, and takes a little under two years for it to complete a single orbit

SpaceX has hired super-hero movie costume designer Jose Fernandez to design space suits for its astronauts.

SpaceX scored a double whammy of successes this morning, May 6, following the stunning nighttime launch of a Japanese comsat to orbit on the firm's Falcon 9 rocket and nailing the breathtaking touchdown of the spent first stage just minutes later - furthering the goal of rocket reusability