New research suggests the moons of Jupiter and Uranus may hint that our planetary neighborhood once had a third ice giant.

The scientific wonderers at What If examine the hidden gravitational mystery of a possible ninth planet lurking in our Solar System. Obama's Colbert remarks trigger Trump's furious online barrage Alex ...

The two planets will be at their closest on June 9, when they’ll be spotted lounging happily together above the northwestern ...

"I think these are not far-out type of ideas; they are not really futuristic ideas that we are talking about." ...

If you have questions you would like answered on Astro Brief, email them to Dr. Mike Reed at mikereed@missouristate.edu. Astro Brief is a podcast collaboration between KSMU, the Missouri Space Grant, ...

Summer officially arrives in the Northern Hemisphere this month, bringing with it balmy evenings that invite us to look up.

Discover the solar apex and how to find Vega this May. Learn about the sun's journey through space and its cosmic ...

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Two decades ago, the International Astronomical Union—which defines and names celestial bodies—redefined the criteria for being a planet, putting Pluto into the new category of dwarf planet ...

The Solar System is the name given to the part of space that surrounds the Sun. Even though it is bigger than anything we can imagine, the Solar System is actually a very tiny part of the universe.

"Make Pluto a planet again," NASA administrator Jared Issaacman said in a Senate hearing last Tuesday. And lo, the Internet did rejoice. Two decades on from its original declassification as a ...