Remember when Pluto was this strange, faraway planet (or dwarf planet, depending on when you grew up) that science textbooks knew very little about? It wasn’t that long ago that we didn’t know things like its true color, composition, or really much of anything about its topography. Well, that’s all changing fast.
Yesterday (Sept. 10), NASA released the most crystal-clear photos of Pluto yet, snapped by the New Horizons spacecraft during its flyby in July. NASA and the Johns Hopkins University Applied Physics Laboratory started the “intensive data downlink phase” on Sept. 5, and information will slowly trickle in from the spacecraft over the next year. Even at light speed, it takes the data almost five hours to travel the 3 billion miles from New Horizons to Earth.
The new high-resolution images unveil what NASA is calling a “bewildering variety of surface features.”
“Pluto is showing us a diversity of landforms and complexity of processes that rival anything we’ve seen in the solar system,” said Alan Stern, head of the New Horizons team. “If an artist had painted this Pluto before our flyby, I probably would have called it over the top—but that’s what is actually there.”
Pluto’s diverse landforms include nitrogen ice flows, vast ridges, mountains, planes, and what are believed to be dunes. That makes Pluto just as, if not more, geologically complex, than our familiar planetary next-door neighbor, Mars.
Dunes are generally created by winds—the movement of gases in an atmosphere—but scientists believe Pluto still has plenty of them despite not having much of an atmosphere at all.
“Seeing dunes on Pluto—if that is what they are—would be completely wild, because Pluto’s atmosphere today is so thin,” said William B. McKinnon, a Pluto researcher from Washington University in St. Louis. “Either Pluto had a thicker atmosphere in the past, or some process we haven’t figured out is at work. It’s a head-scratcher.”
NASA also released a much higher-quality version of the image of Pluto’s moon Charon than the one first seen in July. It turns out that Charon, like Pluto, has a “surprisingly complex geological history.”
