In a paper published Thursday in Science magazine, the team released the first official findings from that data.
"We just have this wonderful first look that says the Pluto system is remarkable," New Horizons project scientist Hal Weaver told The Washington Post.
Many of the results discussed in the new paper sound familiar, because the New Horizons team has been generous in sharing its interpretation of new photos and data with the public.
The paper highlights the unexpectedly diverse terrain of Pluto and Charon. Scientists had thought that the dwarf planet — and especially its largest moon — would have the cratered, collision-scarred surfaces of worlds that had changed little since their formation. Instead, both worlds show dynamic geology, with parts of their surfaces seeming almost impossibly young.
Something is definitely changing the surface of Pluto, but we can't yet be sure what's powering the resurfacing.
"How can these small, cold objects be so diverse? What's driving what seems to be tectonic activity on the surface, these glacier flows, these incredibly complicated regions on the surface that just look like a jumbled mess of giant, icy mountains? The variety of the surface features has been a big surprise," Weaver said.
There are glaciers made of exotic ices, and a mysteriously smooth frozen lake of nitrogen known as Sputnik Planum. In fact, the New Horizons scientists think that some of the glaciers might be water ice bobbing around in pools of nitrogen. It's possible that nitrogen flows on Pluto like groundwater on Earth.
Even the smaller moons have been surprising. It seems likely, based on their level of reflectivity, that some or all of Pluto's small moons are covered in pure water ice. And although we already knew that the moons had incredibly wonky orbits, new data suggest that they are even wonkier than previously assumed: Unlike most moons, Nix and Hydra don't seem to keep one face locked on Pluto.
That's probably because Pluto and Charon act more like binary planets than anything else. They orbit around the same fixed point, facing each other. For little Nix and Hydra, Charon's gravity may make it too difficult to keep an eye on Pluto.
For now, scientists are really just taking stock.
"We’re just trying to put together the picture and assess exactly what we have and just sort of lay out the landscape," Weaver said. "This is our first real display of that to the world."
But with months' worth of data left to analyze, the best is yet to come.
"I think it's only going to get better — so far we have so little of the data," Weaver said.
Even since the paper was written, new results have come back. When the paper was drafted, for example, scientists had yet to see the color images of Pluto's haze — showing that it's a brilliant blue.
Cathy Olkin, the deputy project scientist, agreed that New Horizons had "completely revolutionized our understanding of Pluto."
When asked what questions she is most excited to answer with the data that's yet to come, she hesitated.
"Pluto has been quite surprising so far," Olkin said. "And I guess I'm particularly interested in — well, in all of it."