Snow has been found on Pluto, more specifically on a series of mountains in an area called the Cthulhu Region, announces NASA’s New Horizons team.
The material that has been interpreted to be snow has appeared on peaks of a mountain range that is part of the Cthulhu region of Pluto; it is thought to be methane ice.
Cthulhu constitutes a relatively conspicuous landscape feature of Pluto. It starts from the west of the Sputnik Planum (the plains characterised by the presence of nitrogen ice), extending halfway around the dwarf planet’s equator. The area it covers is quite extensive: around 3,000 km in length, and 750 km in width. It consists of mountains, smooth features, and areas with craters and cracks all over. The snow might have been generated on the peaks of one of its dark-red mountain range in the southeast in the form of a bright layer.
The ‘snow coating’ is easily visible because of its brightness, given that Cthulhu is normally dark, allegedly because of the presence of dark tholins which can be turned to methane by sunlight. The ice would have been formed as a result of the condensation of methane; it might have originally come from the atmosphere of Pluto.
The position of this bright ice on the peaks is said to correlate with the distribution of methane ice, according to compositional data made available by New Horizons spacecraft; it is shown at the right on the above diagram, and the methane ice distribution is depicted in purple.
This material is found only on the higher slopes of the peaks, which led the scientists to suggest that methane ice might be the equivalent of water in the atmosphere of our planet. This methane would condense “as frost at high altitude”, says John Stansberry, from the New Horizons team.