Nasa today also released an image of exotic ice across the dwarf planet’s surface, revealing signs of recent geologic activity something scientists hoped to find but did not expect. The hazes detected in this image are a key element in creating the complex hydrocarbon compounds that give Pluto’s surface its reddish hue,’ said Michael Summers, a New Horizons co-investigator.
This newest image shows the remarkably well-defined topography along the western edge of Tombaugh Region. ‘There is a pronounced difference in texture between the younger, frozen plains to the east and the dark, heavily-cratered terrain to the west,’ said Jeff Moore, leader of the New Horizons Geology, Geophysics and Imaging Team.
‘There’s a complex interaction going on between the bright and the dark materials that we’re still trying to understand.’ While Sputnik Planum is believed to be relatively young in geological terms perhaps less than 100 million years old – the darker region probably dates back billions of years. Moore claims that the bright, sediment-like material appears to be filling in old craters.
Meanwhile, the sharpest image yet received from New Horizons of Pluto’s satellite Hydra shows that its irregular shape resembles the state of Michigan. The new image was made by the Long Range Reconnaissance Imager (LORRI) on July 14, 2015 from a distance of 143,000 miles (231,000 kilometers), and shows features as small as 0.7 miles (1.2km) across. There appear to be at least two large craters, one of which is mostly in shadow. The upper portion looks darker than the rest of Hydra, suggesting a possible difference in surface composition.
Science collaborator Ted Stryk of Roane State Community College in Tennessee said: ‘Before last week, Hydra was just a faint point of light, so it’s a surreal experience to see it become an actual place, as we see its shape and spot recognizable features on its surface for the first time.’