Charles Wood

When I was young and when I was at the Lunar Lab in the sixties, I thought I’d probably go to the Moon. I think most of us, the younger students, thought we’d probably be doing planetary geology on the Moon or on Mars. It was a big disappointment when that didn’t happen. My dream all along has been that we would have people doing work and living on these other places. I think we know now it’s a lot harder than we used to think it might be. But I think we should still do it.

I used to teach, and I would tell people to have a longer perspective. The perspective I used was the orbital period of Halley’s comet. Halley’s comet was last visible in 1986. Mark Twain was born in 1835, and halfway through his life he said he came in with the comet and he’d probably go out with the comet, and he died when Halley’s comet came the next time. That’s 76 years. If you think in terms of 76 years as one cycle, if you think back to the 1500s, 1400s, and every time Halley’s comet came close to the Earth before that, the people on Earth were pretty much living in an agricultural environment. There were flare-ups of culture in Greece and China and places like that, but pretty much life was fairly agricultural.

When Halley’s comet appeared in the 1500s and 1600s, the scientific revolution had started, the Renaissance had started. The first scientific society was 1669 in England. As Halley’s comet came every 76 years, the next time it came for the last three or four hundred years, we’ve had lots of technological advances. For example, in 1835, we had the steam engine that was invented; we were doing trains. By the next time it came, 1910, airplanes had been invented. By the next time it came, in 1986, computers had been invented, spaceships had been invented. So if you look at how much change there was between one time Halley’s comet was near the Earth and the next time, it’s just phenomenal. It’s almost unbelievable, the technological changes that have occurred.

So I assume that the same sort of unbelievable changes are going to occur between 1986 when it last here and the next time, 2050 or whenever it is. I think the next time it appears that there will be people on Mars studying it as it goes past Mars, and they’ll be people on the Moon studying it as it goes past the Moon, and they’ll be other people flying in spaceships alongside of it as it comes into our solar system so we can study it better.

The time after that, that Halley’s comet comes, about 150 years from now, we’ll be living throughout the galaxy. The rate of technological expansion is just extraordinary. So if we don’t kill ourselves because of environmental degradation or nuclear war or something like that, humans will be throughout the galaxy. It doesn’t seem to me it’s so much of an extrapolation. You should be planning what your life is going to be in the solar system, not just what your life is going to be on Earth.

Joe Giacalone

We’re literally in the golden age of planetary science, there’s no doubt about it. I mean, going to Mars, going to Saturn, going to Jupiter, going to the Moon—the textbooks literally have to be written constantly to keep up with the new information. Planetary science is just growing like crazy.

Solar physics is an area that is expanding, and there’s a lot of emphasis on understanding how the Sun works. It’s been recognized fairly recently that the Sun itself undergoes changes. It’s got the 11-year sunspot cycle, and it becomes active and can have these huge solar storms that can affect communications and things. This is kind of a new area of research that’s come up, that’s been given the blanket term “space weather” or “living with a star”—buzz words that have come about. That’s been the big emphasis for the last five to ten years. When I came here in ’93 I don’t think “space weather,” that term, had been invented yet.

Renu Malhotra

The major exciting thing for me now in the last two or three years is inner solar system and the bombardment history of the planets. Now that we have strengthened the idea that there was indeed a cataclysmic bombardment, there are still many unanswered questions about it. What exactly was the mechanism that made the asteroids turn into projectiles at that time? It’s very exciting to be able to probe the early history of the Earth and inner planets, and one of the things that is especially interesting to me about it is that any mechanism that explains the late heavy bombardment is going to have something to do with what was going on in the outer solar system too.

As it turns out, to launch the asteroids out of the asteroid belt and into the inner solar system, you likely have to use the gravity of the big planets, Jupiter, Saturn, Uranus and Neptune. That means that what was going on in the outer solar system had a profound effect on what happened in the inner solar system, including the Earth.

Just being able to connect such diverse areas—to be able to connect what is essentially planetary geology with orbital dynamics, and the terrestrial planets with the outer giant planets’ history—I think this lab is probably one of the very few places in the world where something like that could happen, because of our diverse range of researchers.

Dante Lauretta

There are a lot of meteorite dealers that show up at the Tucson Gem and Mineral Show. I started going to that, and I met Marvin Killgore, who was at the time a meteorite dealer. He’s one of the rare meteorite dealers that was very interested in meteorite science and was preserving these at his expense—basically not selling all his best stuff, so he could keep it and do research on it and provide it to scientists for research.

We realized that the commercial meteorite world was in a crazy state right now, with millions of dollars being traded in meteorites, and meteorites being harvested at very rapid time-scales compared to the rate at which they fall on Earth. This was kind of a bonanza, similar to a Gold Rush period in the 1800s, and it was going to die out like the Gold Rush did too. All the good meteorites were going to be recovered, and if we didn’t do something to preserve them, there’d be nothing left for future generations to work on.

We decided to try to create this Southwest Meteorite Center, and we hired Marvin at the University of Arizona. He still works for us. We’ve been going for about a year now, with pretty good success. We have some potentially very large donors interested in contributing, which is really what we need in order make this thing a long-lasting success. It’s kind of a save the world crusade that we’re on: Save the meteorites.

Jonathan Lunine

I am involved in two missions that are under development. One is the James Webb Space Telescope, which is the successor to Hubble. I also recently got selected as part of a team to build a mission to make measurements of Jupiter, called Juno, which will really focus on the structure and composition of Jupiter. That should launch in 2011. I’m involved in studies of future missions to Titan, particularly balloon missions.

The field is exciting; the questions have become sharper and deeper. There are a lot of mysteries in the solar system and beyond to understand. I hope I live long enough and the program prospers enough both to find planets like the Earth around other stars and to get this darn balloon to Titan, so we can get a camera all over the surface at close range and really see what’s going on. If those two things can happen, I’ll be tickled pink. If they don’t, it still has been a great ride.

Alfred McEwen

I’d really like to get back to Io. Io was my first love. It’s a tough sell because there are very dim prospects for finding life as we know it on Io. It’s dry, it’s sulfurous—hell, basically. It’s not a nice, warm, cozy place for life as we know it. But it’s spectacular with all the active volcanism. The time hasn’t been right to send a dedicated mission to Io, but maybe that time will come.

Don McCarthy

You would’ve thought that we’d learn everything about the planets by now. But it keeps getting more and more surprising. I am amazed by the activity on Saturn’s moons, the geysers from Enceladus. To be honest, I’m convinced it has to happen on Pluto now. Pluto’s atmosphere has waves in it. Something has to cause the waves. There has to be activity of some kind on the surface of Pluto. It’s too small a place to see it directly, so you’ve got to probably wait until 2015 when the spacecraft goes by. But they should see geysers or some sort of activity on Pluto.

The solar system just keeps surprising, whether it’s individual objects or how they interact with each other. To me that’s one of the most beautiful parts of it, to see the orbital relationships. The solar system has a lot to tell us yet, about individual objects and their general patterns. Then to relate that to other solar systems that are being discovered is pretty amazing.

I think NASA’s about to have another press release that says there’s another planetary system somewhat like ours that’s being discovered. Those are rare. There are very few systems that are like our own. It’s kind of funny because people argue that planets formed from a common process that occurs naturally by the formation of stars. That does seem to be true, but we can’t reproduce the exact details of our own solar system. All these planets are different; where they are, how they’re situated. The Earth may actually still yet be fairly unique.

That could be wrong, because we don’t have the technology to see Earth-like planets yet. But where we are in our orbit, how long we’ve survived, and with the Moon that we have, it seems at the moment to still be very special and unusual.