Thicknesses of Pluto's subsurface layers and possible ocean are yet to be determined! Image credit: NASA/SwRI/JHUAPL

Thicknesses of Pluto's subsurface layers and possible ocean are yet to be determined! Image credit: NASA/SwRI/JHUAPL

Happy Monday, Earthlings!

This week we are going to look at what lurks beneath Pluto's bright heart shape surface. This heart, Sputnik Planitia, is an in-filled impact basin. And a HUGE one at that. 

The impact would have caused extensive stresses and large cracking. For the dwarf planet to "settle" from such an event, two things would need to happen.

First, the in-filling of the basin from any subsurface material to essentially "heal" itself. We see this with most icy bodies where subsurface materials are slushy and cover any exposed areas and freeze. Nitrogen several miles thick has now covered it. 

Second, the impact would have made the orientation of Pluto wobble. Pluto has now regained control for several thousand years and re-oriented itself!

For both things to happen though, according to modeling, a subsurface ocean would have to be a major factor!

What kind of ocean? For it to be denser than nitrogen, the logical explanation would be water. 

But how warm and if there are any salts involved? What about silicate materials? That we are not sure YET!

Stay tuned next week for a look at the 45th anniversary of Apollo 17 journeys!