CAPE CANAVERAL, Fla. — Scientists have discovered dunes on Pluto made of tiny frozen grains of methane.
The pale grayish ridges were revealed by NASA’s New Horizons spacecraft during its 2015 flyby. A British-led team disclosed the findings this week in the journal Science.
Researchers said the dunes appear to be made mostly of icy specks of methane the size of sand, with some frozen nitrogen likely mixed in.
Scientists were surprised to find dunes, given Pluto’s thin, weak atmosphere. Dunes already have been found on Mars, Venus, Saturn’s moon, Titan, and even a comet. But Pluto’s are the only ones known to consist of methane.
Launched in 2006, New Horizons was the first spacecraft ever to visit Pluto, passing within 7,770 miles.