NASA’s New Horizons space probe sent photographs of the area around the dwarf planet Pluto’s north pole taken during the extraordinary July 14, 2015 flyby. The images reveal a series of canyons long and wide in the polar area that at its bottom is about 1,200 km (750 miles) wide. It’s part of the region informally called Lowell Regio after the astronomer Percival Lowell, the founder of the observatory where Pluto was discovered.
The photographs were taken by the New Horizons space probe’s Ralph/Multispectral Visible Imaging Camera instrument from a distance of about 33,900 km (21,100 miles), just before its closest approach to Pluto. The colors were enhanced stressing the unusual yellow hue on the dwarf planet. One possibility is that there are old deposits of methane that suffered the effects of solar radiation longer than the other areas with a bluer tone.
The canyons can be vast: the one shown in yellow in the picture at the bottom has a width of about 75 km (about 45 miles). Those indicated in green and pink are smaller, with widths up to about 10 kilometers (about 6 miles), but still leave deep scars in the area.
The areas shown in red are sort of pits, irregular depressions about 70 km (45 miles) across with a depth of about 4 km (2.5 miles). Their origin suggests the existence of areas where the underground ice melted or even sublimated from the bottom causing the collapse of the ground.
The photographs in their highest definition allowed the New Horizons mission’s scientists to see that the canyons walls appear much older than those of similar formations in other areas of Pluto. This was deduced from the degradation of the canyon walls at Lowell Regio compared to those of other regions.
These canyons could be among the oldest on Pluto, generated by tectonic phenomena that show once again that at least in the past this little world was active. Together with the pits, they are yet another demonstration of the existing geological diversity of this dwarf planet.
The New Horizons space probe has sent almost half of the data collected during its flyby. By now, it’s hard to surprise us with every new geological feature that is revealed but every high-definition photograph allows to find out more about Pluto’s features and history.
