Updated

Updated · Science News Magazine · Jul 10

Researchers Identify 6 Pluto Landslides Up to 130 Square Kilometers From New Horizons Reanalysis

Updated

Updated · Science News Magazine · Jul 10

Researchers Identify 6 Pluto Landslides Up to 130 Square Kilometers From New Horizons Reanalysis

Q: What unique ice physics allows Pluto's massive landslides to slide for miles with almost no friction?

The best current explanation is that Pluto’s landslides are moving on unusually slippery ice mixtures, not dry rock. Researchers say the dwarf planet combines hard water ice with much more volatile nitrogen, methane and carbon monoxide ices, and those materials appear to give the debris an exceptionally low effective friction. That matters because the six newly identified landslides near Sputnik Planitia traveled 10 to 14.5 kilometers despite drop heights of only about 1,500 to 2,200 meters. On Earth or on rockier worlds, slides with those dimensions would usually stop sooner. Their long run-out strongly suggests that Pluto’s surface materials behave differently under collapse. Scientists have not yet pinned down a single exact mechanism. But the leading interpretation from the imagery analysis is that Pluto’s ice physics — the mechanical behavior of volatile ices under Pluto’s very cold temperatures and weak gravity — lets debris keep moving far more efficiently than expected. In practical terms, the ice may deform, shear or act as a lubricating layer in ways that sharply reduce resistance. So the answer is not one confirmed exotic process, but a material-property effect: Pluto’s mix of water ice and volatile ices appears to create very low-friction landslides. Researchers say that is the key insight from the discovery, and more New Horizons analysis or a future mission will be needed to determine exactly how those ices produce such long-traveling flows.

3 articles · Updated · Science News Magazine · Jul 10

Six large landslides have been identified on Pluto, marking the first definitive detections on the dwarf planet; the biggest covers about 130 square kilometers, roughly twice Manhattan’s size.
New Horizons images from the 2015 flyby yielded the finds after researchers reanalyzed the data for steep cliffs and terrain with distinct tone and texture, locating all six along impact-crater rims near Sputnik Planitia.
The features rise about 1,500 to 2,200 meters and appear to travel farther than similarly tall landslides elsewhere, suggesting lower average friction in material moving down Pluto’s slopes.
That low-friction signal could help constrain Pluto’s surface material properties, and the team says more landslides likely remain hidden in existing data pending further analysis and future missions.