Back in the 1980’s, a now-defunct magazine called Science Digest held a contest to name Planet X — the still-undiscovered world that astronomers believed might lie out beyond Pluto. One of the best ...

Pluto may have been demoted to non-planet status, but it still commands a court of five moons, as is fitting for the king of darkness; after all, Pluto is the Roman equivalent of the Greek God Hades.

This composite image of Pluto, right, and Charon, its largest moon, showcases photos captured by NASA’s New Horizons spacecraft in July 2015. Unlike how scientists believe Earth's moon formed billions ...

New research suggests Pluto may have had a “kiss” with its largest moon billions of years ago in a harmless collision. The report, published in “Nature Geoscience,” describes how the minuscule dwarf ...

Pluto pulled Adeene Denton into its orbit during her undergraduate internship at the Lunar and Planetary Institute in Houston. It was summer 2015, when the New Horizons spacecraft zoomed past the ...

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