WHAT DID WE LEARN ABOUT PLUTO FROM NEW HORIZONS?
Among the discoveries scientists are still analyzing:
Instead of an ancient, inert rock, we’ve found an icy world with active processes creating fresh surfaces. The rugged surface of Pluto is younger than the Appalachian Mountains.
One mountain chain near Pluto’s equator is more than two miles tall.
We knew Pluto was covered by ice. What we didn’t know: It’s covered with four types of ice — methane, nitrogen, carbon monoxide and water. Each go through freezing and precipitation cycles. Much of the water ice is beneath the surface.
Pluto is covered by a thin, blue soot-like haze. Scientists think it’s created by sunlight interacting with nitrogen and methane in the atmosphere.
Pluto has an ionized tail like a comet — probably from nitrogen from its atmosphere leaking into the solar wind. Up to 500 tons of nitrogen escape the planet every hour. The tail extends for tens of thousands of miles.
The mass of Charon is so large — and the mass of Pluto is so small — that Charon doesn’t actually orbit the dwarf planet. Instead, both orbit a fixed place in space between them.