(Photo courtesy of NASA/JHUAPL/SwRI)

A view of Pluto.

The first formal results about Pluto from NASA’s New Horizons spacecraft appeared in the journal Science last week.

One of the most surprising discoveries for NASA scientists was Pluto’s glaciers. Slushy slabs of mostly nitrogen ice scrape craters off the landscape — creating the bright heart-shaped region photographed by the New Horizons spacecraft in July.

“That was really mind-boggling when we first saw those,” said Will Grundy, a planetary scientist at Lowell Observatory in Flagstaff and a co-investigator on the mission. “I guess these ices are doing their thing and they’re moving around on very short time scales.”

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Grundy said it’s not clear how Pluto remains geologically active so long after its formation. It might be powered by an internal heat source that melts glaciers just enough to get them moving.

New Horizons also found rugged mountains rising from water-ice bedrock, and dark streaks possibly formed by wind.

The science team speculates that more worlds like Pluto might exist out in the Kuiper Belt. The spacecraft just fired its thrusters to set a course for a Kuiper Belt object.

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