DAVID GREENE, HOST:
Who can blame people at NASA for being just a little excited this week? Ten years ago, they sent the New Horizons spacecraft on a mission. Travel 3 billion miles. Get near Pluto. Take pictures. Gather data, and send it all the way back home. Well, it all seemed to work. Scientists this week are processing what's come back. And it's pretty amazing stuff. Dr. Carly Howett is a member of the team. And she told me new discoveries are being made by the minute about Pluto and its moon, Charon.
CARLY HOWETT: They're not just old, cratered worlds. Across the solar system, we don't expect to see a lot of active geology. Usually, after these bodies have formed, they cool down. And then they get bombarded by craters for years and years and years. So we expect to see very gray, very cratered surfaces sort of reminiscent of our moon. But when you look at Pluto and you look at Charon, there are these areas that are completely smooth. And that's telling us that these areas have been resurfaced at some point in their history. And these bodies are so far from the sun. And there's no big planet nearby. Lots of bodies about the same size as Pluto and Charon have a kind of parent planet, if you like. Pluto doesn't have that. It's sort of lonely in the back end of the solar system. Because it doesn't have this energy source, we were expecting it not to have geology. And it does.
GREENE: And what does that actually mean for a planet or, I guess, dwarf planet. I'm not even going to go there. But what does it mean that Pluto has geology, as you put it?
HOWETT: It means that we don't understand how planets keep and reemit their energy. So we'd expect, like I said, Pluto to sort of be geologically dead - just this heavily cratered surface. And so there's something; there's some process going on that we don't quite understand that's allowing the service to smooth out. And so we're going to be going back to our models, back looking at the data to try and sort of figure out how - how this can possibly be possible. We keep looking at the data, and we don't understand it. And that's just - that's just the best feeling.
GREENE: I mean, you've seen these mountains in some of these images that are the size of the Rockies. And they're made of ice, which I imagine ice is one of the many signs of there being a geology actually on the planet. What are the implications of water being there?
HOWETT: Well, there's actually water ice throughout the solar system. So it wasn't necessarily a huge surprise that it was there. We see it on other bodies. But to see such structure in the water ice is amazing. So these are very, very cold temperatures. And water ice gets very strong. It's almost rocklike at those temperatures. So it's a very different water than we see on the earth. It's so far from the sun. It's so cold that everything has a sort of different regime. And so the fact that the crust is able to support that weight is telling us a lot about the surface. And it's just this new regime that we're just not used to looking at in these details. So it's - there's a lot of scratching of heads and a lot of postulating. And that's what we love the most. So it's great.
GREENE: It looks like this might open the door to a whole lot of questions and maybe a drive toward really researching Pluto more.
HOWETT: I really hope so. Because it's taken so long to get there, we had to go incredibly quickly. You know, it's a one-stop shop. And so I think there are questions. And the only solution - it's so far away - is to go back and kind of hang out in the system or do orbits or to drop a lander.
GREENE: I'm just amazed that some of the images have shown this dark area that looks like a heart on the service. I mean, Pluto was supposed to be a cold, dead rock. And yet, Pluto has a heart. There's something kind of amazing about that.
HOWETT: It really speaks to, I think, what we're all feeling. I fell in love with Pluto very early on in my career. And I think the rest of the world is falling in love with Pluto now. And it looks like it's almost falling in love with us when you see images with that spectacular heart looking back at the earth.
GREENE: Carly Howett, thank you so much for joining us. And keep enjoying this week and all of these images coming back from near Pluto.
HOWETT: I absolutely will. Thank you for your time.
(SOUNDBITE OF SONG, "COLD, COLD HEART")
HANK WILLIAMS: (Singing) Why can't I free your doubtful mind and melt your cold, cold heart? Transcript provided by NPR, Copyright NPR.