This article is more than 1 year old

YOW! Pluto STUNS boffins with HAZY, SHRINKY atmosphere

Probe spots nitrogen ice glaciers flowing into craters

The icy plains of Pluto

Pluto nitrogen flows

Water just don't cut it

Meanwhile, NASA also showed off its highest-resolution image yet of the Plutonian surface, which shows what appears to be rivers of nitrogen ice flowing around mountains and filling in impact craters on the surface.

Much of the ice that surrounds Pluto is water ice, but it's far too cold for frozen H20 to move. The surface temperature at the moment is around -380 Fahrenheit (-228 Celsius), and at those temperatures water ice just gets brittle and immobile as rock.

Instead New Horizons has spotted what's thought to be nitrogen ice flowing on the edges of the flat icy Sputnik plain that makes up part of Pluto's heart-shaped feature informally known as Tombaugh Regio after the planet's discoverer.

Tombaugh Regio is young, just a few tens of millions of years old, as evidenced by its lack of impact craters.

Close-up photography shows that around the northern and southern edges of the Sputnik plain the ice is flowing onto the surrounding landscape and can be seen filling in impact craters in older rocks.

Youtube Video

"Nitrogen ice can creep, and below ground it will warm up a bit," said William McKinnon, New Horizons co-investigator at Washington University. "Tens of meters under the surface the pressure from the overburden will warm nitrogen and enable it to flow. You may even have liquid nitrogen hundreds of meters below the ice."

The big question now is where does this ice come from. It may upwell from a point on the surface, or may be deposits left over from the atmosphere, or even from an extraterrestrial body.

We'll have to wait for the next NASA installment before we get more clues.

Unfortunately that's not going to come for a while. About 5 per cent of an estimated 50GB of data has come back to earth and we won’t be getting any more pretty pictures until September at the earliest. New Horizons will be sending back just engineering data for the next month and a bit. ®

More about


Send us news

Other stories you might like