NOVA; To the Moon; Interview with Leon "Lee" Silver, Ph.D., Professor of Geology at the California Institute of Technology, part 1 of 4

Okay. All right. I want to bring Jim Lovell in at this particular point, because one of the consequences of our sitting in on 14 was that Dave Scott asked that an astronaut, an experienced astronaut, be put in charge of the backroom. Science backroom. Science backroom feeds questions to the moker, to the flight controllers, and through the Capcom on up. But they don't talk directly. Who did we get the best possible guy? Jim Lovell, did you understand? And Jim Lovell had been trained enough and understood enough so that when we explained to him that we wanted to ask a certain question, or we wanted to change, recommended a change in the protocol, Jim could communicate. When Jim Lovell spoke, the moker paid attention. So Dave Scott was very smart in setting that up in there. OK. So now let's go back to the thing. So I don't know what to say. A Northocyte. And now we talked earlier about the Highlands and the Murray.

The brightest rocks that we could think of that might supply the brightness of that is a rock made up of Feldspar, OK? And a Northocyte is a rock made up of Plydeclase Feldspar. When we got the Apollo 11 7 pulls back, a very smart fellow by the name of John Wood at the Smithsonian Astrophysical Observatory looked at small little tiny bits and he said, by God, there may be some pieces of the Highlands in here. Here are these tiny little pieces that are very white. So what these were, the same thing as this chip right here, except see them as one millimeter in size, not as in this case half a meter in size. So we were very conscious of that. Now it turns out that in my looking for training sites, I had one in my backyard, which has the only body of the Northocyte of any significant size on the west coast. And much more, this in Northocyte,

because it's in what we call a tectonically active area, has been shattered and broken and what have you, not exactly like the impact shattering that we have. But it was a good place to give them some experience and to let them know about a Northocyte, OK? Now, the Northocyte has another very important quality. It's a low radioactivity mineral and its isotopic properties probably go back to the time of its origin. So we were very interested in getting chunks of the Highland material. On Hadley Delta, they did not see many rocks. But as they were working on there, they ran across a piece. I think was Dave Scott who picked it up. He said to Jim, look at this. And whoever it was said, yeah, that's what it looks like. They never used the word a Northocyte, OK? And then the other end, back, well, I think we got it.

OK? And they still used the word a Northocyte. We didn't know what it was. But of course, the media picked that up. And in time, it became clear that this was a chunk of a Northocyte. And it is, and was, the best chunk of a Northocyte that we got out of the Highlands. Best, in the sense, it was less butchered, less fragmented, or other things that were just as pure a Northocyte, but they had a more complex history. And it also turned out that it gave us an isotopic signature for what we call the initial strontium AD786 ratio, which is among the most primitive things we've observed about the moon. And far more primitive than anything we'd ever seen on the Earth. So it was clearly important. Well, the media called it Genesis Rock. And the story was that we had sent them up there to get that rock.

And that any robot who'd been programmed would have been able to get that same bowl. These guys knew what they were looking at. They knew this might be important. That wasn't the only thing they collected. But they were well enough prepared that they recognized its potential importance and they collected. It's about not even that big, maybe that big. Beautiful rock. Show you a picture of it. What about the green rock? A hard soil. All right, the green rock. On Apollo 15, they saw this green stuff. Confirm that it was green. It was really the first color rock other than white or gray or black. That anybody picked up, when it came back, it was confirmed that it was made up of little beads of glass. Now, when I used glass in a geological sense, this is stuff devoid of crystals. It had not had an opportunity. In the surface environment of the Earth and the Moon and most of the planets, we don't preserve glass very well.

It's temporarily there, but it goes over to crystals. This was crystals. Beautiful, gem-green crystals. And we took note of it. We didn't do the right experiment on it right off the bat, but it was there. It was recorded. We got to Apollo 17, and we were going to a place called Shorty's Crater, Crater 4. I mean, stop number 4 on the EVA station 4, I should say. And in that stop, scuffling around on the rim of the crater, one of them looked down. I always had difficulty. I could not distinguish the timber of Schmidt's voice versus Cernan's voice when they were excited. I couldn't tell them apart, and I knew them quite well. But one of them said, hey, look at that. Orange soil. Now, have you ever been to Hawaii? If you've been to Hawaii, you'll notice that there are a lot of cinder cones scattered around.

And some of those cinder cones are dark brown to black. And some of them are quite red. When they're red or orange, they usually reflect an oxidation of iron contained in the rock due to interaction with steam, which many of those things emit. By the time we got to 17, we'd learn the hard way. We had never seen any evidence of the presence of a drop of water, a molecule of water on the moon. And I thought that what these guys had finally found was, at short, this crater was a volcanic crater, and this is a place where...