John Spencer from Southwest Research Institute’s Boulder-based planetary science division is the deputy geology and geophysics lead on the New Horizons mission. Simply put, he’s the guy who interprets the images from New Horizons to explain the geology on Pluto.
He’s been working with mission primary investigator Alan Stern on a Pluto mission since 1993.
We caught up with Spencer Tuesday morning, shortly after New Horizons passed Pluto.
Q: How are you doing? I know your team was up particularly late last night working on the latest image release.
A: Yeah, I got about an hour’s sleep. This is a once in a lifetime experience so it’s a small price to pay.
Q: What’s on the docket for today?
A: I am going to be mostly talking to media and letting everyone know what we’re up to. I’m not going to be able to look at the data today, but we had a pretty good look at it last night … and it gave us a basic view of what Pluto is like from that one image, which is hugely exciting but I think for more in-depth stuff, for me it’s going to have to wait a little bit until I can catch my breath.
We’ll get better pictures tomorrow anyway, so whatever we do with today’s data is going to be obsolete by tomorrow.
Q: What we’ve seen today is so groundbreaking and amazing. What’s the biggest discovery you’ve seen so far, and what do you expect?
A: I think the biggest discovery for me is that Pluto has a complicated geological history. It has some old areas — we know they’re pretty old because they have craters them and we can see things which were are pretty sure are impact craters where asteroids or a comet had smashed into Pluto a long time ago. And then we see some areas that look very smooth where something, we have no idea what yet, has erased those craters or buried them so we have a much younger landscape with fewer craters on it.
That’s really basic information about Pluto that we had no idea about before yesterday. It’s one of the things I’ve been wondering about for a long time is how active is Pluto geologically? Is it an ancient surface or a young surface? And now we see maybe it’s both.
Q: Knowing that the images and information you have today is going to be obsolete tomorrow, what do you think you’ll see?
A: Tomorrow’s pictures will be nearly 10 times better than today’s. We don’t see the whole planet at that resolution — we see a small part of it — but that small part, we’ll see in amazing detail.
We also get our first decent views of the small moons, Nix and Hydra, which up to now have been little more than just points of light. We’ll get to see what shape they are, maybe see some features on their surfaces, certainly see just how big and how bright they are. We get a better view of (Pluto’s moon) Charon as well, about twice as good as we have up until now. There’s stuff coming thick and fast from now on.
Q: How long have you been on this project?
A: Alan Stern first asked me to help out with a Pluto project in 1993 and he’s been working on it longer than that. The New Horizons mission started in 2001. The first time I came out to the Applied Physics Lab for the proposal review was in October 2001, when we tried to convince NASA that we had a viable project and they should pay us to build the spacecraft.
I remember we had a cardboard mock-up of the spacecraft in one corner of the auditorium for that. And now, nearly 15 years later, we’ve got the real one flying past Pluto this very day. It’s mind-boggling to think about.
Q: That has to feel incredible. This has been Alan Stern’s life work, and it sounds like it’s a huge chunk of yours as well.
A: Certainly the last few years, it’s taken over my life, as it has many other people. It will be the middle of August before I’m able to catch my breath back in Boulder, and I’m certainly looking forward to that.
Q: So if the mission is extended, I understand you have a big role to play in that. Tell me about the Kuiper Belt object exploration.
A: We’ve spent several years looking for objects beyond Pluto that we could reach with New Horizons in this vast, unexplored part of the solar system, the Kuiper Belt, which Pluto is a part of but Pluto is also kind of on the inner edge of. So out beyond Pluto there are thousands of small worlds, which we know almost nothing about and we are very interested in flying past one of those worlds.
We’ve been searching for years for a possible target, and then last summer, with the Hubble Space Telescope, we actually found a couple of objects that are close enough to our path that we can actually reach them with the fuel that we have. So we have to decide in the next few weeks, really, which of those we are going to go for, and then in the fall we will fire our engines to set a course to one or the other of those objects. We can’t go to both, unfortunately.
And then we have to apply for further funding for that extended mission, so this is currently hypothetical but we have to make the plans and set the course before we actually have the money. That’s just the way the timing works out. We can’t wait until everything is guaranteed because then we’d be too close and it would take too much fuel to change our course to get there.
I haven’t really been thinking about the budget,but it won’t be nearly as much as the Pluto mission. This will be a smaller operation, and we already have built the spacecraft, of course, so we already have all those assets paid for.
Q: What kinds of things can we learn by extending the mission and exploring further into the Kuiper Belt?
A: Pluto is a very interesting object, but it is also a very unusual object in the Kuiper Belt. We just found out last week from New Horizons measurements that it’s the largest object in the Kuiper Belt and it has a complex history, as we’re now seeing in the images.
These objects that we could fly by later are like the building blocks that Pluto, and other worlds like it, were made of. And they may even be the building blocks that even the giant planets were made of, because a lot of this material is the sort of stuff that would have formed the planets, but has failed to coalesce into planets and has been left on the shelf out here in this pristine part of the solar system. So we’re very anxious to see what they look like up close, what their surface compositions are — whether they have craters on their surface, what those might tell us about the objects that have bombarded them, whether they have satellites maybe. So we’ll be doing a lot of work that makes the case that this is science that NASA should pay for and I think we can make that case.
This is going right back to the origins of our solar system out there in the Kuiper Belt
Q: Last question: Do you think what we’ve seen from New Horizons will cause the “is Pluto a planet?” debate to be reignited?
A: I kind of hope not. I think what we’re seeing here is that Pluto is an amazing place and we’re focusing on what Pluto is, rather than what it is called. And what it is, is astonishing. People have differing opinions about this. To me, the importance is what it will tell us about our origins, and that’s good enough for me.
Laura Keeney: 303-954-1337, lkeeney@denverpost.com or twitter.com/LauraKeeney