Liquid Nitrogen May Have Recently Flowed Across Pluto’s Heart-Shaped Glacier

Evidence of Subsurface Liquid on Pluto

The dark features are concentrated in the northern section of Sputnik Planitia, a nitrogen-ice glacier spanning roughly 1 200 x 2 000 kilometers—an area larger than Texas and Oklahoma combined. Alan Stern’s team identified two distinct types of markings: narrow dark lines tracing convection cell boundaries and broader, diffuse dark aprons. Both phenomena mirror the appearance of surface moisture left by meltwater on terrestrial glaciers. Because Pluto’s surface hovers near minus 230 degrees Celsius and its atmospheric conditions render liquid nitrogen rain physically impossible, researchers conclude any active fluid must originate from below.

How Researchers Modeled Basal Flow on Pluto

To test how liquid could exist at minus 230 degrees, scientists compared New Horizons flyby imagery with satellite data of the Greenland ice sheet captured by NASA’s Landsat 9. Orkan Umurhan of the SETI Institute constructed computer models demonstrating that internal heat rising from Pluto’s interior can melt nitrogen at the base of the glacier, several kilometers beneath the surface. Liquid nitrogen is less dense than the solid ice above it, allowing it to ascend through narrow channels like magma on Earth before flowing downhill and darkening the surface ice.

The models point to short-lived eruptions rather than a steady trickle. Each event is estimated to release between 100 000 and 1 million cubic meters of liquid over hours or days. For scale, an Olympic swimming pool holds about 2 500 cubic meters, meaning a single Plutonian outburst would fill between 40 and 400 pools.

Unresolved Questions and Study Limitations

The research team explicitly categorizes their findings as potential evidence rather than confirmed fact. No spacecraft has directly observed liquid flowing on Pluto, and the New Horizons data remains a single snapshot captured during its 2015 and 2016 flybys. Kelsi Singer, a lead researcher at the Southwest Research Institute and co-author of the study, acknowledged that Pluto features unique terrains unlike anything on Earth, meaning terrestrial comparisons have distinct physical limits.

Researchers also emphasize that more than half of Pluto has never been mapped in high resolution, leaving open the possibility that these dark streaks are widespread or rare across the dwarf planet. NASA published its own summary of the findings in August 2026, opening fresh discussions about whether similar processes occur on other Kuiper Belt objects, Neptune’s moon Triton, or the dwarf planet Eris.

Frequently Asked Questions About Liquid on Pluto

Is there liquid on Pluto right now?

It is not confirmed. The study suggests liquid nitrogen recently reached the surface in northern Sputnik Planitia through intermittent episodes rather than a continuous stream, but no direct observations exist.

Can it rain liquid nitrogen on Pluto?

What is Sputnik Planitia?

It is the smooth, bright nitrogen glacier that forms the western lobe of Pluto’s heart-shaped region, covering an area larger than Texas and Oklahoma combined with a surface age under one million years.

Where else in the solar system could this happen?

Researchers suggest similar subsurface melting processes could occur on other distant bodies containing nitrogen ice, specifically pointing to Neptune’s moon Triton and the dwarf planet Eris.