Psychedelic Pluto

Observations by NASA’s Curiosity Rover indicate Mars’ Mount Sharp was built by sediments deposited in a large lake bed over tens of millions of years, challenging the notion that warm and wet conditions were transient, local, or only underground on the Red Planet.

Earlier this year scientists presented evidence for Planet Nine, a Neptune-mass planet in an elliptical orbit 10 times farther from our Sun than Pluto. New research examining theories how this planet could end up in such a distant orbit finds that most scenarios have low probabilities. Therefore, the presence of Planet Nine remains a bit of a mystery.

Two of Pluto’s mini-moons, the mysterious Nix and Hydra, have transitioned from featureless points of light into their own worlds with new imagery from NASA’s New Horizons spacecraft.