Scientists have released global maps of both Pluto and its moon Charon, using images taken by the New Horizons spacecraft during its historic flyby in July 2015.
Published in the journal Icarus (Pluto here and Charon here), the researchers led by the Lunar and Planetary Institute (LPI) in Texas painstakingly stitched together images to create the maps, giving a detailed look at the two worlds including their mountains, valleys, and more.
Using stereo images from two cameras on board New Horizons, the team was able to create topographic maps for each observed region. Parts of both Pluto and Charon remained in darkness as New Horizons flew past, meaning we won’t know what they look like until a future mission.
But for what we can see, which amounts to about half of each world, we can see some fascinating details. The topographic images confirm that the highest known mountains on Pluto are in the Tenzing Montes range, with the highest peak rising about 6 kilometers (3.7 miles) above the surface, roughly the same as Kenya’s Kilimanjaro.
“Pluto's mountains must be composed of stiff water ice in order to maintain their heights, as the more volatile ices observed on Pluto, including methane and nitrogen ice, would be too weak and the mountains would collapse,” a statement from the LPI noted.
The topographic map also revealed that Pluto’s vast Sputnik Planitia ice sheet, which spans about 1,000 kilometers (625 miles), is an average of 2.5 kilometers (1.5 miles) deep. The outer edges of the sheet are 3.5 kilometers (2.2 miles) deep, making them the lowest areas on Pluto.
And to the west of Sputnik Planitia, which forms the western part of the heart-shaped feature called Tombaugh Regio, the researchers spied a vast ridge-and-trough system that stretches more than 3,000 kilometers (2,000 miles), evidence that Pluto once fractured in its past for unknown reasons.
As for Charon, the topographic maps show that parts of the moon’s north pole are 14 kilometers (8.7 miles) deep, making them deeper than Earth’s Marianas Trench. There’s also evidence for cryovolcanic activity in the fractured northern hemisphere, remnants of Charon’s past.
While the flyby of Pluto and Charon lasted just a few days, New Horizons has given us a fascinating glimpse at these distant bodies towards the edge of the Solar System. The spacecraft itself is on its way to its next target, a body nicknamed Ultima Thule in the Kuiper Belt, which is possibly a remnant of the Solar System’s formation.