A spectacular sampling of imagery from NASA’s New Horizons spacecraft reveals mountains and water ice bedrock on Pluto, an active crust on its largest moon Charon and the first resolved views of the icy world’s tiny mini-moons.
A snapshot of Pluto shows fresh deposits of water ice bedrock and 11,000-foot (3500-metre) mountains, revealing evidence Pluto’s surface is one of the youngest in the solar system. These mountains likely formed no more than 100 million years ago, suggesting the close-up region — which covers about one percent of Pluto’s surface — may still be geologically active today. Unlike the icy moons of giant planets, Pluto cannot be heated by gravitational interactions with a much larger planetary body. Some other process must be generating the mountainous landscape. Photo credit: NASA/JHUAPL/SWRINew Horizons found few craters on the surface of Pluto’s Texas-sized moon Charon, evidence of recent geologic activity. A swath of cliffs and troughs stretching about 600 miles (1,000 kilometres) suggests widespread fracturing of Charon’s crust, likely the result of internal geological processes. The image also shows a canyon estimated to be 4 to 6 miles (7 to 9 kilometres) deep. In Charon’s north polar region, the dark surface markings have a diffuse boundary, suggesting a thin deposit or stain on the surface. Photo credit: NASA/JHUAPL/SWRITuesday’s New Horizons flyby revealed Pluto’s tiny moon Hydra. The first resolved image of the object shows it to be 28 miles long and 19 miles in diameter, and better images are to come. The observations also indicate Hydra’s surface is probably coated with water ice. Photo credit: NASA/JHUAPL/SWRI
The true size of Pluto has been debated since its discovery over 85 years ago. New Horizons’ mission scientists can now answer that question with certainty, confirming that Pluto is larger than all other known Solar System objects beyond the orbit of Neptune.
Dwarf planet Pluto will receive its first robotic emissary from Earth in the form of NASA’s New Horizons spacecraft on 14 July. Since this enigmatic world is also at opposition on 6 July, here’s our guide to finding Pluto with large backyard telescopes.
NASA’s New Horizons spacecraft spied extensional faults on Pluto, a sign that the dwarf planet has undergone a global expansion possibly due to the slow freezing of a sub-surface ocean. A new analysis by Brown University scientists bolsters that idea, and suggests that ocean is likely still there today.
