Scientist are initially wondering what geologic process could have formed these 100 million year-old, that's relative young at the planetary scale, mountains. Since Neptune and Pluto have orbits that cross but they can never collide because of a 3:2 orbital resonance ratio there has to be times when Neptune ( a huge mass ) exerts gravitational forces on the small dwarf-planet.
Found this cool simulation. http://www.orbitsimulator.com/gravity/articles/pluto.html
For you musicians it ought to be interesting that the 3:2 ratio is a perfect fifth. Things that make you go hummm? Harmony of the Universe.
Maybe we are all just bubbles in the quantum soup of cold energy being resonated by He Who Plucks The Strings and that's why human song has the Perfect Fifth as the second most appealing interval.
An image of Pluto with 10 times the resolution of anything ever seen before has been unveiled by Nasa, after the New Horizons probe made a successful flyby of the dwarf planet yesterday.