Pluto's farthest moon is comprised of pristine water ice, making its surface look highly reflective.
Hydra, the outermost moon of Pluto, is predominantly made up of pristine water ice, which is making its surface look highly reflective. That is what scientists have concluded after analyzing the data from the New Horizons spacecraft.
How To: Buy a Pokemon Go Plus
New Horizons has recently sent back the first ever compositional data about Pluto’s four small moons. The data was gathered with the Ralph/Linear Etalon Imaging Spectral Array (LEISA) instrument in July 2015 during the iconic close-up flyby of Pluto, from a distance of 150,000 miles and shows the undeniable evidence of crystalline water ice.
“The new data – known as infrared spectra – show the unmistakable signature of crystalline water ice: a broad absorption from 1.50 to 1.60 microns and a narrower water-ice spectral feature at 1.65 microns.” Authors wrote in NASA blog.
Hydra, alongside Nix, was discovered in June 2005 but scientists knew very little about its geology and compositional properties until the tiny moon of Pluto was visited by NASA’s New Horizons in July 2015.
Hydra is estimated to be 25 miles wide and 34 miles wide, compared to Pluto’s largest moon Charon which is 752 miles across. Charon is also comprised of water ice but new findings suggest that the grains of ice on Hydra are larger and more reflective on certain angles in comparison to Charon. Astronomers assume that Hydra was formed during the same collision between Pluto and another icy body that formed Charon some 4 billion years ago. Hydra’s highly reflective surface indicates less contamination by darker material which has accumulated on Charon’s surface over time, making Hydra’s surface look much more clear than Charon’s.
“Perhaps micrometeorite impacts continually, refresh the surface of hydra by blasting off contaminants,” explains Simon Porter, a member of New Horizon’s team. “This process would have been ineffective on the much larger Charon, whose much stronger gravity retains any debris created by these impacts.”
Don't Miss: The Best HDR TVs
Scientists are hoping to obtain data of Pluto’s other small moons and compare it with Hydra and Charon to better understand their composition.