GCRG logo - waves above name with sheep
 Gene Shoemaker
  BQR ~ winter 1999-2000

e considered himself a scientific historian, one whose mission in life was to relate geologic and planetary events in a perspective manner. He brought geologic principles together with the mapping of planets, resulting in more than three decades of discoveries about the planets and asteroids of the solar system.
Gene Shoemaker began exploring for uranium deposits in Colorado and Utah in 1948, and these studies brought him to the many volcanic features and the one impact structure on the Colorado Plateau—the Hopi Buttes and Meteor Crater. During the late '50s, he did his classic research on the structure and mechanics of meteorite impact, and invented the Branch of Astrogeology within the United States Geological Survey.
It is said that Gene Shoemaker longed to go to the Moon as an astronaut and study its geology firsthand. A medical condition kept him from doing that, but he helped select and train the Apollo astronauts in lunar geology and impact cratering. He led teams who were investigating the structure and history of the Moon and developing methods of planetary geologic mapping from telescope images.
Obviously, Gene was a smart man. He soon figured out how to make work by combining his knowledge of the geology of the Colorado Plateau with his love of river running, and came up with the idea of rephotographing the pictures taken on John Wesley Powell's second exploration of the Colorado River in 1871–72. Gene and his partner identified and rephotographed almost every one of the Powell trip's camera stations nearly 100 years later. Their work, “In the Footsteps of John Wesley Powell,” was published in 1987, and marked the beginning of the photo matching work that now continues.
Gene Shoemaker died in 1997 from injuries sustained in a car accident while in Australia studying impact craters. The following year Gene got his wish to travel to the moon, when a capsule carrying a small amount of his ashes traveled aboard nasa's Lunar Prospector spacecraft. On July 31, 1999, after eighteen months of successful orbital scientific operations, Lunar Prospector was commanded to crash into the surface of the Moon. At his journeys' end, Eugene M. Shoemaker became the first inhabitant of Earth to be sent to rest on another celestial body.

've been working around on the Colorado Plateau since 1948. I've had a long lasting love affair with the Green and Colorado Rivers. In 1949 I went with some friends down Glen Canyon. Then later on just boated on the river recreationally, all over on the river system. But…[there] was a project I undertook in 1968. It was a project I had dreamt about doing from 1954, when William Culp Darra published the first biography of John Wesley Powell. It was a good biography. In this book Darra mentioned the pictures that had been taken on the second Powell expedition. I decided right then and there that would be a wonderful project, to go back and find the camera stations of the photographs taken by the photographers with Powell. I kind of had in mind well, it would be something I would do when I retired. But in 1967, late 1967, I got home from a trip, back to Flagstaff, and read the hometown paper, the Daily Sun, and discovered there that the U.S. Geological Survey [usgs], Smithsonian Institution and the National Geographic Society were going to plan a centennial celebration of Powell's first trip down the river, in 1869. I made up my mind right then and there, now is the time to do that project. I promptly invited myself on the organizing committee. I approached the director of the Geological Survey and was able to get support to undertake a summers' long trip, in 1968, starting in Green River Wyoming and ending at the Grand Wash Cliffs, more exactly at Pearce Ferry. We tried to recapture all the camera stations that we could, from the beginning of the second Powell expedition through to the end. I started out with Hal Stephens who was my primary partner in this and who was to be the photographer on our trip. We'd jointly located sites and I took the detailed notes of each one. We organized the trip in six sections…and the trip lasted about three months. We did indeed start off at exactly the same point that the Powell party started on their second expedition. Of course, we knew where it was because we had the photographs. In fact we photographed several sites around the town of Green River. Recaptured some of the sites that E.O. Beaman, who was Powell's initial photographer, had taken.
Of course a number of the sites as we went down were covered over by Flaming Gorge Reservoir, backed up behind Flaming Gorge Dam. I had seen the river before the dam was put in. But we were able to locate fairly closely whole series of those sites. Below Flaming Gorge Dam we then had the open river again. Down through Red Canyon, Browns Park, down into Lodore Canyon. And indeed, the second Powell expedition took a lot of photographs up in that part of the trip. They became somewhat more sparing of the photography as they went further downstream. On the second segment, then, we took the boats out at Dinosaur National Park, put them back in again at the head of Desolation Canyon, actually at the Ouray Indian Reservation. The third leg of the trip was from there on down to Green River, Utah. Then we had another group join us. We hop-scotched then, and the next segment was down through Stillwater Canyon and Cataract Canyon. In fact Tad Nichols and his son-in-law came up and met us by boat. By that time the reservoir was already getting pretty high behind Glen Canyon Dam. They gave us a tow out to the new site of Hite. But we did get some interesting Powell shots actually somewhat up out of the river banks. Some Indian ruins that they had photographed and some interesting inscriptions of the Powell party, on the rocks, now under water. Then we had to just portage around Lake Powell and put the boats back in at Lees Ferry…[and] continued that work on down through Grand Canyon.
Turned out that E.O. Beaman left the Powell party midway through the 1871–72 trip. Powell and his crew wintered over in Kanab, Utah. Beaman had a falling out with Powell. Powell bought out Beaman's share of the photographs and equipment. He hired a new photographer out of Salt Lake City who actually did go back out. They had cached one boat at the mouth of North Wash. The party went overland and discovered the Escalante River. This is on horseback. Thompson was in charge of that, and they went back and recovered the boat that was cached there with a complete set of photographic gear. They took pictures coming down Glen Canyon the following spring. The photographer that Powell had hired really wasn't physically up to it. He was fairly sick. In the meantime he succeeded in training John Hillers, whom Powell had hired in Salt Lake City as an out-of-work mule-skinner, who had become a boatman on the trip and had just picked up photography. Having been trained a little bit along the trip, he turned out to be a superb photographer. The rest of the photographs taken down through the Grand Canyon were taken by Hillers instead of Beaman. We spent about a month, starting at Lees Ferry and taking out at Pearce Ferry; recovering Hillers' camera stations all the way down through Marble Canyon and on down through the Grand Canyon. Actually the Powell party took out in the summer of 1872 at Kanab Creek. They had a supply coming in on horseback at Kanab that brought supplies down to the river to re-supply. They were going to re-supply but the river was so much higher than Powell had seen it in 1869 that he decided the better part of valor was to abandon the river at that point. So Hillers took a series of pictures going up Kanab Creek, which we did follow out on foot for about eight miles up Kanab Creek. That was about as far as the remaining pictures go. It turns out that during the winter encampment in Kanab, Hillers had gone with Powell's cousin and scrambled down from Toroweap Valley down to Lava Falls. So there were a series of Hillers' pictures taken at Lava Falls. Even though the second expedition didn't actually make it to Lava Falls on the river, we had a very nice sequence to recover there. So that was as far downstream as we had photographs to recover from that second expedition.
***
Eugene Shoemaker
1928 ~ 1997
In 1994 a little handful of gcrg regulars got to go on an unbelievable trip. We started out calling it the “Legends Trip” but then that seemed kinda puffed-up after awhile (especially to all the other Legends that didn't happen to be on it), so pretty soon we dropped that for the “Old-Timers Trip,” which wasn't totally true either, or at least only in a relative sense. But there actually were a few Legends on it, and one of them was Gene Shoemaker. He was a world famous astro-geologist who had received the country's highest scientific honor, the National Medal of Science in 1992. He had been all over the pages of Time Magazine recently for discovering—along with his wife Carolyn and one David Levy—the Shoemaker-Levy Comet, which had then smacked Jupiter in the midst of great fanfare and applause here on Earth. And as if that alone weren't enough, here he had a river history too.
He only had time to go to Phantom Ranch and so we banged out a short interview with him. We hated to see him go, because his good spirits and plain-spoken style had added immeasurably to our own enjoyment on this river trip. He was a young man though, a mere 62, and in pretty good shape. So even though we weren't all that happy with the half-assed interview we'd done on this trip, we figured, as we watched him disappear around the bend, we'd catch up to him again sometime down the road.
***
How valuable is photo matching to the United States Geological Survey? What do you get from matching these things?
We were basically the first persons, Hal Stephens and I, to go back and do this kind of thing.

Nobody had thought of it.
Nobody had ever gone back and tried to match photographs. It soon became a popular sport. [laughs] A lot of people got into going back and looking at old photographs. And matching the sites to see what the changes were.
We really had two objectives in this work. One of them was simply to develop a good descriptive album of the beautiful work that Hillers and Beaman did. They deserve to be recognized as pioneer photographers of the west. While Jackson and several others had gotten quite a reputation, there had never been systematic publication of the photographs from the second Powell expedition, which was really pioneering work. So my first objective was really to publish these photographs—get them known to the public. Do it in a way to describe what's there and to give these pioneers credit for what they had done. We intended the book to be out in time for the Powell Centennial, but what happened was that I left the full time employment with the usgs in the end of 1968 and went to Caltech. While we had all the photographic material ready, and the maps, there just wasn't time to bring it all together. The book was published after Stephens retired and had the time to sit down and finish pulling it all together. So we didn't make that one objective of getting the work out for the Powell Centennial, which was the initial intent. The second intent was that I hoped to learn something about the nature of the changes in this country. I had no idea what we were going to discover because no one had ever done it before. It's an ideal place—coming down through the canyons of the Colorado Plateau. It's one of the least disturbed areas. If you exclude the dams and all, the areas that have not been affected by the dams—that's one of the least disturbed areas left, in the conterminous United States. So you see what my idea was; to try to understand something about the rates of geologic processes. The rates of change on the river bank or in the side canyons. The canyon walls—what I found was a surprise, frankly. We found that in 85 percent of the cases when we went back and located a scene there was hardly any change at all, either in the background or the foreground. Small rocks on steep slopes were still in the same place. Cobbles on the river bank were in the same place—that was a big surprise—in most cases. It was only in the remaining 15 to 20 percent of the cases that we actually saw the changes. What was really interesting was there were very few intermediate cases where there were just a few changes. Either the whole foreground scene was changed or there was hardly anything disturbed. Just a few cases where, say, one or two rocks had been moved. That brought home to me, that the nature of geologic processes that sculpt these canyons, and for that matter sculpt all of the landscape, is such that very little happens over most of the time. Most of the change takes place in very rare events. Usually caused by storms. They will be flash floods on the main river. They will be debris flows on the side streams. Or a section of the cliff falls off. At any one place the change is basically catastrophic. Nothing happens for hundreds of years or sometimes even for a thousand years. Then there will be a catastrophe, a local catastrophe that changes the landscape. I think we're coming to understand now, that that is the way most geologic processes work. Geomorphic processes. That they are dominated by the rare several hundred year flood, or thousand year flood, not by the annual events or the decade-al events, which has been the view that has been embedded in the consciousness of geologists…. There was a view that you could go sit on the bank of a stream and see what was doing the work on an average day. And it's not true. Very little happens on the average day. It's that one rare day in a hundred thousand in which most of the geologic change occurs. So that was…that was kind of a revelation from that book.
That preceded, of course, the work that is now ongoing, the beautiful detailed studies that are being carried out by Jack Schmidt and Ted Melis and Bob Webb. The way they've gone back now and looked at many many other photographs, more extensive photographs like Stanton's collection for example. And turned these photographs into a beautiful scientific resource for really understanding the frequency of these events in the canyon.
How are the Stanton photos? How do they compare with Hillers' or Beamans'?
Stanton took a very good set of photographs too. They were much more extensive in the Grand Canyon, by an order of magnitude over what Hillers took, ‘cause he was trying to document the route of his proposed railroad. The Stanton collection, I don't know the exact number, is some order of a thousand photos. Vastly more extensive data that dates back to the late 1800s. So it's now been a century since Stanton's time. They actually provide more details, more scientific information than was available from the Powell photographs. But the basic story was there in the Powell photographs. If you take the photographs, not just from the Grand Canyon but from the whole river system right up through the Green, all the way back to Green River Wyoming, you have a pretty good sample of the Colorado Plateau in those photos.

Are the Stanton photos telling us the same thing?
Somewhat to my surprise when I just looked at the frequency of changes from the Powell pictures, my estimate was that at any one place something catastrophic happens on order of about once every 500 or a thousand years. Somewhat to my surprise, they're finding from the Stanton photographs, and from more recent photographs, that in some of these side canyons the frequency of flooding—serious flooding and debris flows—is much higher. Higher than I would've guessed. In some cases there have been multiple debris flows, such as at Prospect Canyon, in the course of less than 50 years. I would've had no way of knowing with the small coverage that we had from the Powell photographs. But I am surprised. I still think that at any given place, if you look at these really enormous debris fans that we see, there are occasionally huge floods that I think are on the order of every thousand years, that build a major fan. Then you have smaller debris flows in between time, that make small modifications to that. The truly big fans in this section of the canyon probably are built with the frequency of about once every thousand years or so.
***
I should mention that there were multiple purposes in the Grand Canyon part of our 1968 trip. We were doing a series of guide books. In fact, the guide book for this part of the Canyon, which was written by Simmons and Gaskill was one of those specific things. In addition, Tad Nichols and his son-in-law were along and Tad was taking photography specifically for a documentary on Powell, as a part of the Powell Centennial. So we were meeting a number of objectives on the trip in addition to Lee Silver's work with the sampling to study the crystalline precambrian rocks. One of the little amusing parts of getting the publications going on the guide books you might be interested in…the Powell Society really didn't have any money except what the members themselves, which was a very small group, might put in. So we were trying to figure out how to get the first guide book published. The idea was to get it published and to sell enough guide books that that would amortize the cost. Then we could publish the next guide book and get a whole bunch of them going. So someone came up with a bright idea. Might've been Henry Toll or Dave Gaskill, “Why don't we give a big public lecture on the trip?” So I agreed to do that, and they hired a big auditorium in Denver, the Phipps Auditorium. I had a whole set of slides worked up. They were the old three and a quarter by four lantern slides on glass. There were these great big projectors. And we filled the hall. We got a tremendous take. It worked! And I had this special set of slides that showed on one projector a picture taken by Beaman or Hillers. On the other projector it would be the matching photograph by Stephens. I told this story, that in most cases there was no change. You could see the same boulders sitting there on the river bank. Then in the small 15 percent case you could see dramatic changes. Then we finished the lecture with Stephens' movie that he had put together with the materials that he shot with this small waterproof wind up motion picture camera that we carried down with us. So the lecture was a smashing success. We published the first guide book. But you know the funny thing is that lecture wouldn't die. I thought I had prepared that material for a one shot deal. And I kept on giving that lecture for years and years. It was so popular and people would see it at one place and word would get around, next thing I'd know they would want me to give it some place else. I kept on giving that lecture for twenty years.
Your first trip through here was in 1968, when you were doing the Powell match up. But you started boating in the 1950s?
I started boating in 1949 just with friends, you know. After 1951, Carolyn and I with other friends would run Cataract Canyon, or the San Juan or up through Flaming Gorge. In fact we spent some time getting around making sure we ran through all of the canyons before they disappeared under reservoirs. So we, for example, went back down the San Juan and the lower part of Glen Canyon the year just before the canyon was closed with the construction then. Say a last good-bye to it…
Working on the Colorado Plateau I knew the geology intimately, over a broad area. That's of course what made it possible. Having seen all the canyons and the upper part of the river system, and knowing the geology is really what made it feasible to do that 1968 trip, and know where to look, and get all the pictures sorted out. It turned out that the photographs were not very well identified. The photographs from the second Powell expedition had plates. These old classical wet plate photographs had gone into the usgs collection and never been systematically cataloged. There had been an album of prints made from these plates, but it was all mixed up with other things. It was something that was done in Jack Hillers' lab. Jack Hillers went on to become the chief photographer for the usgs when the Powell Survey was amalgamated with the other surveys in 1879. Hillers had those plates and they were just part of the survey collection. I would judge that it was about twenty years after the trip that someone sat down and tried to identify—and say oh yeah, this picture was from here and that was from there. My hunch is that Thompson did it, but I'm not sure. Thompson was really the guy in command of the river trip, most of the second Powell expedition, because Powell himself was off making trips back to Salt Lake City and working on logistics and things. Most of the captions were reasonably close. But you couldn't tell for sure where they were. Some cases they had the pictures on the wrong river. So it was a task to sit down and figure out where these photographs were taken. Those were the first order of detective work. Having done all the previous boating on the rivers was a good head start to finding these things…. We didn't know how tough it would be. It turned out we hit our schedule right on the nose. There were a few we didn't catch. We realized we had gone past them and it was too late. Just a few in that case. We lost a couple prints in the river when we were running through a rapid or something. But we recovered most of the existing pictures. Actually there is a story about that collection itself that most people don't know. During the 1930s there was an edict that went out that the Government had to reduce its files. So a decision was made that the collection of negatives was going to have to be reduced in the usgs photo lab. Believe it or not they actually removed, presumably destroyed, some of the original plates from the Powell Expedition. The man that made that decision was Julian Sears, who was assistant director at the time. I have a hunch that those plates still exist somewhere. Can't imagine that they broke them, and threw them away. [laughs] But we did have prints, at least had the prints, even if the original negatives were gone. Some of the pictures that we published are just from those prints. The original plates don't exist anymore.
***
What was [your first Glen Canyon trip] like?
That was a total surprise. Our very first trip when we went down Glen Canyon, there were just two other companions with me. One was a young lady geologist, who was Doris Blackman. She is now Doris Weir, who I have known over the years. In fact she has just retired from the usgs. Another was a draftsman by the name of Ken Gardner. We all worked in the usgs offices in Grand Junction where the uranium exploration program was being carried out. We came down in Ken Gardner's home made car, made out of various pieces and parts of other vehicles. We called it the Gardner-Mobile. In fact there was a Gardner car. He actually had hubcaps that said Gardner on them. [laughs] We drove very slowly down North Wash and in those days there wasn't much of a road. Camped over night in the wash and ended up down at Hite—at the Ferry that was run by Art Chaffin. It was an interesting thing in itself, that old Ferry. We got down there fairly early in the day. So we had these two dinky little river boats from Sears Roebuck that we tied end to end. [One of those became known as the good ship Sink-well.] And Gardner was going to go along behind in the one boat, 'cause he only had one hand. He had sawed off his hand in a sawmill as a young man. He'd made his own hook and he could paddle that with a kayak paddle. With his hand and his hook. Doris and I were going to paddle up front, and that's the way we were going to go down this river. Well, Doris and I had paddled around a little on the Gunnison River. We had a pretty good idea how to do it. But we had never put these boats together and paddled with Gardner. We put the boats together and said “Well, let's take a little spin out in the river, out by the Ferry.” And we dang near didn't make it back to shore, because we were not coordinated.
Well we knew…Doris and I knew…a few hundred yards down the river and we'd get coordinated all right. But it scared the daylights out of Gardner, because his density was actually greater than water and he couldn't swim a stroke. He was deathly afraid of the water. So there we were, trying to persuade Ken that it was OK to go. And we went to bed that night thinking “Well, the river trip is over because Gardner isn't going to go with us.” We woke up the next morning and here comes a row boat, down the river. Turned out there had been a party that camped at the mouth of North Wash about five miles upstream that night, unbeknownst to us. This fellow pulls in at the Ferry to talk to Chaffin, and we go out to find out who it is. And it's Bert Loper. Turns out he is leading a whole troop of boy scouts—about 50 boy scouts—coming down the river. They weren't there yet. They were coming behind him. When Gardner found out who it was and we learned what he was going to do, we persuaded Ken that if we got the boats packed up and got ahead of Loper, that he would be safe. So that's what we did. [laughs] We packed up and got out there on the river ahead of Loper and the boy scouts. And that's how we got launched on the river. We pretty much stayed ahead of Loper until we got down to Rainbow Bottom, at the mouth of Aztec Creek, where you used to hike up to Rainbow Bridge. We were hiking up then and we had a pretty good visit with Loper there. Then we learned that his plans were to join his friends at Lees Ferry, and continue on down the Grand at that time. Part of the story was that Loper had gone down the Grand Canyon ten years before…and they'd made a pact with each other that if Loper lived to be 80 years old they would do it again. And this was the time. In fact Loper would've been 80 in the Canyon if he had made it on down. We of course pulled out at Lees Ferry and drove home to Grand Junction. But Loper and his friends came on down.
That was the one [Loper's last trip]?
Yes.
***
Well…how old do you think the Canyon is?
I have very strong prejudices about that because I've worked in the upper end of the system, in particular the Little Colorado River Valley. Worked on theGene and Crater Bidahochee Formation. I'm confident there was a through-flowing stream going west, or north-west, across the Kaibab Uplift in Miocene time, but it was not connected to the lower part of the Canyon, that's clear. The lower part of the Canyon can not be much older than about four million years. But there was the beginning of the cutting of the river as it crosses the Kaibab uplift, at the nose of the Kaibab Plateau, which is much older. I think there was an integrated drainage system. There was a Colorado River System with its tributaries that was probably here on the Plateau, sort of in the configuration that you see now, going all the way back to the beginning of Oligocene time about 30 million years ago. But the river clearly didn't go out through where the lower Colorado does now. It must've crossed, I believe, over the Basin-and-Range province and emptied into the Pacific somewhere along the latitude of northern California now. You know…that's still an open story. But the upper part of the Colorado was then captured by the lower Colorado working up from the Gulf of California, which is a very young feature geologically, in the last four million years.
What turned you toward Astronomy?
I got into Astronomy through the back door. I was interested in the idea of going to the moon. In fact this idea came to me rather suddenly in 1948, shortly after I joined the Geological Survey. I had been a student at Cal Tech and was familiar with the development of rockets that had been going on at the Jet Propulsion Laboratory…and that they were flying these rockets as upper stages on the captured German V-2s. I just got to thinking about that. “You know, they're going to go to the moon in my professional lifetime. They are going to send human beings to the moon.” I made up my mind right then and there that I was going to be standing at the head of the line when the time came for scientists to be chosen as lunar explorers. This was ten years before nasa was founded. I just simply took those turns in the road that I thought would lead me to being the best prepared field geologist to go study the moon. I had an opportunity to go study Meteor Crater, Arizona. I had been working on volcanic craters at the Hopi Buttes, which in fact have forms that are rather similar to some of the smaller lunar craters. I thought I ought to be working on impact craters as well, so I did seize that opportunity. Having worked on an impact crater, the first question a geologist asks is, “Well, how often does this kind of thing happen? What is out there? What kind of bullets are out there that hit the earth that make craters?” I immediately made it my business to find out what was known about earth-crossing asteroids at the time. There wasn't a lot. In fact there were about eight of them known at the time I worked out at Meteor Crater. In fact, most of them had been lost. Only a few of them had well determined orbits. In the meantime the lunar program did come along. As it turned out, I didn't become an astronaut because my adrenal cortex failed just a couple years before scientists were chosen. I ended up chairing the National Academy's ad hoc selection committee instead of being one of the guys standing in line. But that wasn't the reason for getting deeply into studying the geology of the moon…I started a lunar geologic mapping program, in the usgs, funded by nasa, and we continued to study craters. It was important to study craters to be able to interpret what we were seeing on the moon. So my first involvement with telescopes was actually in working on lunar geology, ‘cause we had to go to the telescope to get higher resolution than was available in even the very best telescopic photographs we could work from. In fact, I had a telescope built, near Flagstaff on Anderson Mesa, where we carried out part of that program of observations to work out the critical details for unraveling the stratigraphy of the lunar surface. So that was sort of my first direct involvement with telescopes. Later when I went to Cal Tech to become the Chairman of the Division of Geological Planetary Sciences, I hired a young woman to work with me by the name of Elenore Helin [Bruce (from pro) Helin's mom]. I set her on the task of tracking down every scrap of information we could find about the discovered earth-crossing asteroids. I'd seen an opportunity to work on that problem. It turned out there were only thirteen that had been discovered by that time, all of them just accidentally. We finally decided that the best way to get any further knowledge was to go search for them ourselves. So I started a program and Helin actually carried out most of the observations with a small Schmidt telescope on Palomar Mountain, where time was available to do the work. It turned out to be an ideally suited telescope for the work, so being at Cal Tech was an important step in having been able to start that. That started in 1973 and ended in 1983. Then Carolyn and I started an observing program on Palomar, and this year will basically be our last year of work on that telescope. So it's work that has been carried on for more than 20 years.
It's hard to fathom all that stuff going on out there. Just to think about…trying to figure out what's going on as far as out there as Jupiter. Did your comet really make a big bang when it hit? [Refers to the Shoemaker-Levy Comet which collided with Jupiter in July of 1994.]
The comet did its thing at Jupiter. All these years, you know I've kind of had a daydream…it would sure be fun to see a real impact in my lifetime. They are rare enough that the odds of that weren't very high. Of course I rather imagined, maybe, it'd be a small asteroid that would hit the earth maybe deep in the outback of Australia where nobody would get hurt, and I'd rush over and map the crater. If I'd really thought about it, I would've realized that if I were going to see any impact of a comet or an asteroid during my lifetime, the most likely case would be Jupiter, because the frequency of impact on Jupiter exceeds the frequency on any other planet. Partly because it's bigger, it has a very large gravitational field of influence. So it focuses the flux of comets onto it. But I hadn't really gone through that calculation. This was really a daydream. So it was a matter of extraordinary good fortune that we actually discovered a comet in 1993, in March. First of all it was broken up. It had gotten so close to Jupiter, it had been pulled apart in Jupiter's gravitational field. Then we learned, with further tracking by many observatories around the world, that this object was in orbit around Jupiter. And finally it became clear it was going to actually hit Jupiter when it came back to its closest approach to Jupiter. That was all just an incredible series of surprises. Then of course, we're trying to figure out, “Well, what's really going to happen?” Many people worked on this problem. There was a wide range of opinions. Some people said “Oh, we're not going to see anything at all. Those comets are going to disappear without a trace.” I was pretty sure we were going to see some results that we could resolve with the telescope. In fact with colleagues, we obtained calculations of the plume that's produced by the hot fireball generated by the impact—how high it would rise, how long it would take, how far it would spread out. Those calculations were finished only about a week before the first impact. It would've been sooner but we had trouble getting the funding to do the work. [laughs] Finally National Science Foundation decided, well, I'd been co-discoverer of the comet…it would be kind of a shame if they didn't give us a little funding to work on it too. So we finally got our calculations done late. But I was absolutely delighted because the first nucleus that hit Jupiter produced a plume that we could see on the edge of the planet with the Hubble Space Telescope. It was very close to the plume that we'd calculated. At that point I knew we were going to really see something!
***
I used to be really kinda proud of being a boatman and living down here and being tapped into all this cosmic awareness that you get, just from contemplating the canyon and the amount of time that's involved here. You know, if you buy into the standard geologic line. But it wasn't until I took some astronomers down that it really jerked my head up, to think of people who are looking way, way out there. Where does boating fit into a life as varied as yours? Where do this river and river running fit in?
The world's a tremendously interesting place. There are so many interesting problems, but for me, I really cut my professional geological teeth on the Colorado Plateau. It's been my geological backyard for 45 years, and it's a geologist's paradise. There is no other way to describe it. Rocks are exposed here in a way that you just rarely find anywhere else in the world—a tremendous variety of things to work on and fantastic scenery to go with it. So it's an old love that keeps tugging me back, while I may have my head off in the stars somewhere or the planets and comets, moons, asteroids, it's important to come back and bang on rocks. I still consider myself a rock-knocking geologist. In fact, I'm still doing regular field work in Australia, mapping impact craters there. Coming back to the canyon country and especially the Grand Canyon is just sort of a rejuvenation, gets your geological juices flowing again. There are a whole series of problems down here that have not been solved. I look at them as I go down, and a couple of them I've actually started to work on. But I've got so many irons in the fire, it's hard to finish them.
***
[On the '68 trip] down the upper canyons on the Green and the Colorado, I had this arrangement worked out with a group of guys who called themselves the Powell Society in Denver. And the mainspring in that Society was a forensic pathologist by the name of Henry Toll. They had incorporated themselves as a non-profit outfit to make themselves official and they went around and did the same thing I'd been doing with friends: going down these various canyons before they turned the water off and they started building a dam. But they had had some experience and most of the Powell Society guys had been down the Grand Canyon several times, and I was glad to have them go along. Then we got here and we had several more boats. I'd just brought two assault boats down the river from Wyoming, but down here the Powell Society guys brought some more boats. So, we actually ran four boats down the river, and put two people in each boat. We just had them rigged with rowing frames. No, I'm sorry, we had five boats. We started off and I said “I'm in good hands.” Here are these old hands on the Grand Canyon. I'd never been down the Grand Canyon myself.
We got to Badger Rapid and we all got out there on the right bank and looked it over. “Ok, let's go run it.” We ran most of the boats down and I looked back up and here was a boat flipped in Badger. I won't tell you who it was. I thought “Well, ok, these are experienced river runners. What have I got myself into here?” We got down to Soap Creek and flipped another boat! “Oh, boy this is going to be some trip.” [laughs] Actually the second was really a kind of a fluke flip. It was just one of those things that happens to you, catching the curl of the wave in the tail waves. Things settled down after that. We did flip one more boat down at Crystal. By that time Crystal was pretty mean. It was a hard one to get through. We ran all the boats through successfully, except the first one. We had a great bunch of guys. I had with me, in addition to the Powell Society, Leon T. Silver, who was professor at Cal Tech, who was the real expert on the crystalline precambrian rocks—the older precambrian rocks in the Grand Canyon. He had been working with the samples that had been collected by a Cal Tech/Carnegie Institution trip. In fact I think there was more than one trip, in the late 1930s. He'd come in by helicopter and collected additional samples, but he had never been down the river. This was the time for him to see the river, and he really, thoroughly enjoyed it. And he started collecting like mad. And he took big samples. Well, he was loading most of these samples on the boat that was rowed by Henry Toll. This was just a ten man assault boat. This boat was getting heavy and heavier. It was just darn near getting unmanageable.
Toll was undoubtedly the best boatman. He was good. Well, we are camped at the mouth of Tapeats Creek and as we're camped there we see a commerciaGene on the Riverl trip coming in. If I remember right, I think it was Sanderson. And we discover it's a Barry Goldwater party, on the boat. It was not Barry Goldwater Senior, it was Barry Goldwater Junior in the party. They pulled in on river left about a mile downstream. Silver gets to thinking about this. We've got a good boat there. I think Toll knew the boatmen running the boat. “Maybe they can get those guys to carry out these rocks!” So early the next morning we all stood on the bank and Toll and Silver took off to go on down the river, row across and go talk to the Barry Goldwater party. And it turned out that Toll pulled just one of his very rare boo-boos. He went over a little bit of a drop over a rock. Silver was sitting on the back of the boat and just tumbled right out. ‘Course it wasn't any heavy water or anything and he scrambles right back on. They row over there and Silver strides out of the boat, of course, dripping wet. Walks up to Barry Goldwater, pulls out his card, hands it to Goldwater and introduces himself. [laughs] Goldwater says “Well, I like to do business with a man who bathes before breakfast.” Actually they did talk them into hauling out most of those samples for Silver. Took them on downstream for us.
Oh man…did you worry on that trip? How did it feel to get to the bottom? Did you worry about Lava [Falls] and all that stuff?
Nah, I didn't worry too much about the rapids. 'Course I hadn't seen all these rapids before.
Were you running a boat?
Sure, running my own boat. In fact I had George Anderman with me. He and I jointly owned this boat for years, and boated together. And he hiked down the Kaibab trail and joined us at Phantom Ranch. Yeah, we looked over Lava, it looked pretty scary, not having run it before. In fact a couple of guys lined their boats down. Elected not to run. And I was glad they did. About that time Bruce Julian who had actually flipped one of the boats up at Soap Creek, knew a good line through Lava. And he ran it perfectly. We watched him go and I thought I could hit that line too. But it was very hard to see that exact spot upstream as you know…don't know exactly where to go and it drops off so fast. I missed it by about four or five feet. It dropped right into a hole. Got trapped in this hole—boat just stopped. I lost Anderman instantly. He hung on with all his might onto the rowing frame, but just peeled right off into the rapid. There I was, and the boat was just slamming around and all my bags that I had tied down carefully were starting to come loose. The oars were flailing around at that point. I thought I better get out of this boat before I get pinned in it. I just worried that if it flipped over I might get stuck in the boat. So I got out. And just about that time the boat popped out of the hole. Boat never did flip over. It went over the big wave down at the bottom. Stayed upright all the way and I went through in my life preserver. Which is a non-recommended way to run Lava. I've never yet flipped a boat on the river. But I have had a few episodes.

 
big horn sheep