As celestial bodies go, Pluto is far more surprising than anyone could have expected.
“Pluto is showing us a diversity of landforms and complexity of processes that rival anything we’ve seen in the solar system,” said New Horizons Principal Investigator Alan Stern, of the Southwest Research Institute (SwRI) in Boulder, Colorado, in the official Nasa announcement that also claimed scientists were ‘reeling’ from seeing the new pictures.
“If an artist had painted this Pluto before our fly-by, I probably would have called it over the top – but that’s what is actually there,” added Stern.
The surface is a hotch-potch of terrains. Heavily cratered regions sit next to smooth plains, giving planetary geologists a profound puzzle to solve. The number of craters on a world’s surface indicates its age – think of them like scars that accumulate with time as asteroids and meteorites hit the body.
Scientists had expected Pluto to be heavily cratered across its whole globe because no one knows how such a small planet could produce enough heat to melt its surface, erasing the craters, and producing the young looking, smooth plains.