Methane and nitrogen glaciers on Pluto expand and "grow" in response to temperature changes on the dwarf planet, new research suggests.
Pluto, once considered the ninth and most distant planet from the sun, is now the largest known dwarf planet in the solar system. It is also one of the largest known members of the Kuiper Belt, a shadowy zone beyond the orbit of Neptune thought to be populated by hundreds of thousands of rocky, icy bodies each larger than 62 miles (100 kilometers) across, along with 1 trillion or more comets.
New Horizons' epic Pluto encounter took place five years ago. Celebrate the anniversary with a look at some of the probe's most dramatic and intriguing photos.
Though Pluto is now famously frigid, it may have started off as a hot world that formed rapidly and violently, a new study finds.
The list of Pluto's neighbors just got considerably longer, potentially boosting scientists' odds of finding the putative Planet Nine.
Pluto's discovery wouldn't have been possible, astronomers have realized, without the calculations of a mathematician whom history has forgotten.
Pluto's heart-shaped feature, which NASA's New Horizons spacecraft discovered during its epic July 2015 flyby of Pluto, drives atmospheric circulation on the dwarf planet, a new study suggests.
NASA's New Horizons mission turned Pluto from a fuzzy blob into a detailed, geophysically complex world. But it's still a little fuzzy, as it turns out.
A year after New Horizons buzzed its second target, Arrokoth, a wealth of science has been revealed.
As the 2010s come to a close, it's time to revisit how some of the biggest space science stories shaped the decade.
Hopefully you weren't too attached to "2014 MU69," because the most distant object ever explored has a new name.
The long-standing debate over Pluto's planethood recently got a public boost from NASA Administrator Jim Bridenstine, who said the world should definitely be a planet.
New Horizons made an epic flyby of a Kuiper Belt object to ring in the New Year — but scientists need brand-new observations to truly understand that data.
Pluto lost its "official" planet status over a decade ago, but fans of the solar system's underdog are still rooting for it. And NASA Administrator Jim Bridenstine is one of them.
Buried oceans like the one sloshing beneath the icy surface of the Jupiter moon Europa may be far more common across the cosmos than scientists had imagined.
A surprisingly gentle merger between two small primordial bodies formed the distant object Ultima Thule, a new study suggests.