|Manu||Date: Tuesday, 28-May-2019, 8:04 PM | Message # 1|
|MICHELLE STARR 20 MAY 2019|
The Solar System might be a soggier place than we previously thought - even in the glacially cold reaches of the Kuiper Belt. There, dwarf planet Pluto could be harbouring liquid oceans under a shell of nitrogen ice.
It was thought that the temperature required to maintain a liquid ocean on Pluto was too high for the thick ice to remain unmelted, but Japanese astronomers have found a new possibility: A layer of gas under the ice and above the liquid, insulating the two from each other, and allowing them to coexist.
This could help solve the gravity anomaly detected by the New Horizons probe in the form of the Sputnik Planitia, with its equatorial location and low topography, suggesting a liquid ocean underneath.
A liquid ocean underneath Sputnik Planitia could also explain tectonic features on the planet. And yet, based on Pluto's age and location, scientists expected that all liquid should have frozen solid.
"To maintain an ocean, Pluto needs to retain heat inside. On the other hand, to maintain large variations in its thickness, Pluto's ice shell needs to be cold," the researchers wrote in their paper.
"Here we show ... that the presence of a thin layer of clathrate hydrates (gas hydrates) at the base of the ice shell can explain both the long-term survival of the ocean and the maintenance of shell thickness contrasts."
Read more/full article/source - https://www.sciencealert.com/icy-frozen-pluto-could-have-liquid-oceans