PLANETARY GEOLOGY • RESEARCH EXPLAINER • OCTOBER 24, 2026
Six Giant Landslides on Pluto: What New Horizons Revealed
Evidence level: Peer-reviewed geomorphological analysis of spacecraft imagery and topography, not direct observation of landslides in motion.
A surprising discovery in old data
Scientists revisiting images captured during NASA's 2015 New Horizons flyby identified six large landslide deposits along the inner walls of three impact craters near Sputnik Planitia. The results were reported in the journal Icarus in 2026. Researchers recognized characteristic head scarps, disturbed slopes, blocks and accumulated deposits rather than watching a slide happen.
How big were they?
The mapped slides descended approximately 1.5–2.2 kilometers, with debris extending 10.1–14.5 kilometers downslope. The largest mapped deposit covers roughly 130 square kilometers—an area comparable to a sizable city. One landslide lies in Coughlin crater, two in Giclas crater and three in another crater without a formal name.
Why could material travel so far?
The deposits appear remarkably mobile relative to their vertical drop. Pluto's weak gravity and the mechanical properties of icy materials may help explain the long travel distances, but the available data do not identify a unique cause or precise friction mechanism. Possible triggers include impacts, tectonic processes, slope instability, and temperature-driven changes in surface ice. A smaller nearby impact crater is a possible trigger for the Coughlin feature.
What this does—and doesn't—prove
The study provides the first clear geomorphological identification of landslides on Pluto and shows that gravity-driven mass movement has shaped its terrain. It does not establish when the landslides occurred, that they are happening today, or that the particular deposits were triggered by any one process. The six examples are not a complete inventory: much of Pluto remains insufficiently imaged at this resolution.
Why it matters
Pluto is not simply an inert ball of ice. Understanding slope failure there helps planetary scientists compare the geology of distant icy worlds with that of Earth, Mars, Ceres and Pluto's moon Charon. It also illustrates how a single spacecraft encounter can support new discoveries years later when researchers ask fresh questions of existing data.
Sources
Science News: “Pluto has landslides” (July 10, 2026)
NASA: Pluto in enhanced color (New Horizons imagery)
Image note: Dramatic scenes depicting a city or settlement beneath a landslide are artist's illustrations, not photographs of the event.