Astrophysicists discovered that Pluto's heart-shaped feature, Tombaugh Regio, was formed by an ancient oblique-angle impact.

Astrophysicists from the University of Bern, NCCR PlanetS, and the University of Arizona have solved the mystery of Pluto's heart-shaped feature. They found that the region, named Tombaugh Regio, was formed by an ancient, slow oblique-angle impact. This discovery answers years of questions about the strange shape and geological composition of the dwarf planet's surface, as seen in detail during the 2015 New Horizons flyby.