Air Date: Week of October 27, 2006

An image of the moon produced using a ten-inch Mead telescope. (Photo: Gene Faulkner, NASA.)

It's been 37 years since the last man was on the moon, and now, NASA says, we're going back. The U.S. space agency will send astronauts to the moon as soon as 2019. Living on Earth’s Bruce Gellerman talks to Dr. Neil deGrasse Tyson, director of New York’s Hayden Planetarium, about the draw of moon exploration.

Transcript

CURWOOD: The waxing moon is less than full in the night sky right now. But it has received a lot of attention down here on Earth recently. U.S. scientists announced that they've found a piece of the moon in Antarctica. Meanwhile, the European Space Agency deliberately crashed a probe into the moon. And now, NASA says that after 37 years, we're going back. Neil deGrasse Tyson, an astrophysicist and director of New York’s Hayden Planetarium, sat down with Living on Earth’s Bruce Gellerman to talk about the moon revisited.

GELLERMAN: You know, we all know who the first person on the moon was in Neil Armstrong. But do you know who was the last person?

TYSON: Yeah, well, because I’m kind of, you know, I hang out with some of these folks. The last person on the moon was Gene Cernan.

GELLERMAN: Yeah, but that occurred in 1972.

TYSON: Yup.

GELLERMAN: That’s over 30 years ago.

TYSON: One can make an even stronger, possibly more depressing statement that 1972 Apollo 17 mission was the last time anybody left low Earth orbit.

GELLERMAN: Well, why is it depressing? I mean, did we learn something from the moon that we wouldn’t have known had we not landed men on the moon?

TYSON: Well, there are two ways to think about the Apollo program. One of them is, well, what did we learn scientifically about our activities on the moon? The Apollo program wasn’t really ever about science. It just wasn’t. It was about beating the Russians. And so when you look at the six missions and ask when did the first scientist go to the moon among those missions? You ask what mission was that? It was the last mission, that was Jack Schmitt. He was the first scientist to leave low Earth orbit, took him to the moon, and he was the last scientist to ever do so.

But space exploration, or rather, exploration as a human enterprise, historically has never been driven by science. Make a list of the greatest explorers there ever was, they were simply not driven by science. They were driven by other forces that were at work at the time. There were economic forces, military forces. But, regardless, the previous astronauts, though they weren’t scientists, had their marching orders from scientists on the ground saying ‘pick up rocks of this kind and this variety and bring them back because they could be a tremendous value to our understanding of the Earth-Moon system.’

GELLERMAN: And were they?

TYSON: Yes, indeed. Oh, by all means. In fact, before the Apollo era we could not have spoken with confidence about the formation of the Earth and Moon system, and now there is a consensus view about how that formed, which is remarkable. In the early solar system, we now know that it was quite a shooting gallery. And the Earth didn’t cool off from having getting slammed by asteroids and comets for about 600 million years. And so over that period, one such impactor was large enough to, sort of, sideswipe Earth and cast its debris into orbit around Earth which then coalesced to form the Moon. And all this is post-Apollo era understanding of the Earth-Moon system.

GELLERMAN: Well, why not just send robots up there? Why do we have to have the risks and costs of going there with people? It’s very expensive.

TYSON: Yes, to send people instead of a robot is anywhere from 10 to 100 times more costly. And it’s…for a bunch of obvious reasons, of course, the safety concerns are much greater when you’re sending people than when you send a robot. Plus, people usually want to come back.

GELLERMAN: Well, that would be nice.

TYSON: So part of your expense has to be all that it requires to carry the fuel with you that you would then use to come back. Then you want to feed the people and keep them comfortable. Robots don’t need to be comfortable by our standards, and you hardly have to feed them. You give them a battery pack, and it can recharge from the sun, and they are happy. And, of course, they never have to come back. If your only reason for going into space were science, then wearing my scientist’s hat, I would say, no, never send people. What are you doing? Give me the 100 missions I’d otherwise be able to fund using robots. But last I checked, no one ever named a high school after a robot. So, there is something importantly vicarious about sending one of our own into space.

GELLERMAN: In Antarctica, just recently they found a golf ball-size piece of Moon rock there. How do we know it’s really from the Moon and not some other planet or system or…

TYSON: Excellent question, because we’ve now been to the Moon! And we can now compare the two and say, ‘hey, this rock that’s been on my shelf, that’s a Moon rock for goodness sake!’

By the way, the Moon is not the only place from which we’ve found meteorites. Another kind of meteorite here on Earth are from Mars. And we only know that because we’ve been to each of those places, and have analyzed samples, and then compared them with these meteorites here on Earth and they’re bang on.

GELLERMAN: Well, since we know all this about the Moon already, what’s to be gained scientifically from sending people back there again?

TYSON: First of all, what we now know about the Moon is just what we now know about the Moon. That doesn’t mean we’re done with knowing things about the Moon. The Moon is a tremendously interesting place, geologically. But not only that, but it does represent a whole other place to do science that you might not have otherwise been able to do from Earth’s surface or even from Earth orbit. Now, maybe there won’t be much. That is to be determined. And it just takes some clever creative people, who, at the turn of the century, not this most recent turn of the century, but from the 1900s to 2000, who then was thinking, you know a telescope in orbit would be just smashing. No one was thinking that. They were thinking let’s put a telescope on a yet higher mountain. And so the scope of what was possible had not yet been fully realized until the space age was opened up.

GELLERMAN: Like they say, “to boldly go.”

TYSON: (laughs) We fixed the split infinitive. “To go boldly where no one has gone before.” And, in fact, in that “Star Trek” opening where they say, “Space, the final frontier,” I think of it as space, the next frontier. Who knows what frontier we have yet to reach? What next frontier lies beyond space itself? I like to stay open-minded about these things.

[MUSIC: Star Trek SFX “Transporter” from ‘Science Fiction Sounds’ (Columbia River Entertainment – 2001)]

CURWOOD: Neil deGrasse Tyson is director of the Hayden Planetarium in New York, and host of the PBS program “Nova Science Now.” He spoke with Living on Earth’s Bruce Gellerman.