 |
 |
||
 |
|
||
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
||||||||
 |
Planetary News: Cassini-Huygens (2004)A Conversation with Charles Elachi Director of JPL, and NASA Advanced Planning, Principal investigator Cassini RadarOn the Magic of the Night Sky, 'Listening' to Titan, and Believing Anything is PossibleInterview by A.J.S. Rayl22 October 2004 Charles Elachi was born April 18, 1947 in Rayak, Lebanon. He received a B.S. in physics from the University of Grenoble, France and the Diplome Ingenieur in engineering from the Polytechnic Institute, Grenoble in 1968 where he graduated first in his class. He continued his education at the California Institute of Technology (Caltech), earning M.S. and Ph.D., degrees in electrical sciences there in 1969 and 1971, respectively, and in 1978 received an MBA from University of Southern California and an M.S. degree in geology from University of California at Los Angeles in 1983. He is currently the director of the Jet Propulsion Laboratory (JPL), and was recently appointed NASA Director of Advanced Planning. He also serves as Vice President of Caltech, where he is also a Professor of Electrical Engineering and Planetary Science. On top of all that, Elachi has continued to do the science and is presently the Team Leader of the Cassini Radar instrument and a co-investigator on the Rosetta Comet Nucleus Sounder Experiment. AJSR: I'd like to start out by traveling back in time, back to the beginning -- what or who inspired you or stimulated your interest in space and planetary exploration? CE: I was always fascinated with scientific space and exploration -- and so I don't remember any one moment saying, 'I want to be an astronomer.' Probably it goes back to when I was a kid. It's always hard to tell when things click and actually happen, but I remember when I was 8, 9, 10, 11 -- around that time -- when it was warm in the summer in Lebanon, I liked to sleep outside in a sleeping bag and I'd look up at the sky and watch the stars. I always remember wondering -- what's up there? Are there other people out there lying in their sleeping bags somewhere on some other planet looking at me? I think something about that impacted me and got me into astronomy and physics, and science -- the beauty of the sky and the stars. I remember very clearly when Sputnik was launched I was listening to it on the radio in Lebanon . . . and when I was 12 or 13, I used to read a magazine that the American Embassy distributed, called something like 'Science in America,' an informational magazine. And I remember very clearly reading about the first satellite launch -- Explorer I -- by a place called JPL. I remember that magazine and that page very clearly where I read about JPL, because I thought, 'Gee, that would a great place to work.' Of course, I never imagined then that I would be connected with JPL in any way -- it was so far away. Throughout most of high school, I was fortunate to have had a great science teacher -- George was his first name, and I remember his face very well. He was quite humorous and made science a lot of fun. He certainly inspired me to get involved in science. And your parents? My parents, Rokos and Yvonne, had only high school educations, but they used to always encourage me to do whatever I wanted to do. They would tell me -- 'The sky is the limit as long as you work hard.' I was just a boy in a little town in the Middle East, like a thousand other little boys, but my parents always would tell me that whatever I could dream, if I worked hard at it, I would get there. All of these things were inspirations. So how, exactly, did you get to JPL? I did my undergraduate work in France and then applied to schools in the U.S., for my Ph.D., and I came to Caltech. The reason I selected Caltech was because my professor in France was a roommate to a professor at Caltech -- Charles Papas, when they were both at Harvard finishing their fellowships in graduate school. He said, 'This would be a great person for you to work with for your Ph.D.' He taught electromagnetic theory, and electrical sciences was the field I was interested in. A few weeks after arriving at Caltech, I found out that the university manages JPL. I had no idea that JPL was in Pasadena. So it was through a series of rather unpredictable events that I ended up at Caltech. When I found out Caltech was connected to JPL, the second year I was here, 1969, I applied for a summer job at the laboratory and got the job. I liked it so much that I dropped the Ford Foundation Fellowship that I had so I could work at JPL. I couldn't do both. That's what happened. And you obviously never looked back. Now, among a number of other positions about which we'll talk in a minute, you are the Team Leader on the Cassini imaging radar instrument -- known as synthetic aperture radar -- an area of real expertise for you. The radar data collected by Cassini will be used to reveal the ever-mysterious surface features of Titan. Would you explain in lay terms what synthetic aperture radar is and how you will use it to image Saturn's largest moon? The radar instrument is an instrument that is very similar to the weather radar that you can look at every morning and see where the precipitation is happening, or police radar, which law enforcement officers use to catch speeders. They send a signal with their radar gun that bounces off the car and the signal comes back and is analyzed by computer for the strength of the returned pulse, the time it took to travel to the object and back, and something that is called the phase shift of the pulse - and they can tell how fast you were driving. The Cassini radar is, in theory, based on the same principle. It uses radio signals similar to those emitted from the radios and TVs that everyone listens and watches. The technique of using radar on spacecraft has developed over the last 30 years, and we have used it in many Earth applications, and, particularly, we used it to image Venus, on the Magellan mission. In fact, all the mapping of Venus was done with the radar and the reason is because Venus is completely cloud-covered, similar to Titan, which is completely haze-covered. During the close flyby of Titan coming up, we will send signals from the spacecraft that will propagate, hit the surface of the moon and reflect back from the surface - and we will capture those reflected signals. Since all of the instruments on Cassini are fixed, the spacecraft spins to put each device where it needs to be to make its measurements or observations, and as the spacecraft moves, we record with the radar instrument a series of 'echoes' or information signals that are coming back. The data are returned to JPL where we combine all these 'echoes' together. By combining all of that information, by looking at the surface from different directions, we can generate effectively very high-resolution images, almost identical to black and white photography. Which explains, in part anyway, why everyone is so excited about what this radar instrument will reveal about Titan on the closest flyby October 26 --? Yes. Just like your radio and TV work irrelevant of whether it's cloudy or clear, the same logic applies here. The Cassini radar instrument is a powerful observing tool, because it can "see" through cloud cover, snow and darkness, and, at Titan, the haze that has prevented us from seeing the surface. On Tuesday evening the flyby occurs, and by late that night, or very early Wednesday morning depending on where you are -- West Coast or East Coast, we'll be processing that data. That means we'll be combining those information signals coming from different angles. We should have images between 7 and 9 am on Wednesday morning, Pacific Time. We'll be waiting. What do you hope to find or achieve with this experiment? I would say -- always -- it's a surprise. There have been a number of models about what the surface of Titan looks like: some people say it's completely covered with oceans; others say there are lakes of methane and ethane and bizarre kinds of oil-like materials; still others predict we'll find new geological structures we haven't seen before. Every time we have flown by a planet -- as you know from Voyager, Galileo and Cassini -- we are always surprised. We always find things we don't expect. Nobody ever thought there would be active volcanoes on Io, but that's what the Voyager team discovered. On Titan, we might find geysers of oil or maybe volcanoes. I think we'll be on the edge of our seats looking at the first images. Is there anything you, personally, are looking forward to most on the Cassini mission? Really -- it's seeing what Titan looks like. It's like the typical exploration -- someone's out exploring and all of the sudden you reach a new continent -- and you say -- 'Wow -- what is this? I've never seen this before.' And there's that moment. After that moment, I hope the data sheds much light on how this system evolved. I do think Titan is going to be a big surprise for all of us. We are looking forward not only to next week -- because next week we just get a glimpse of this moon, but we're looking forward to the next four years because we'll be flying by Titan almost every month. And what is it about Titan -- would you elaborate a bit on the moon itself? The reason Titan is particularly exciting is because it is a satellite that has an atmosphere, which is the same pressure as Earth's atmosphere. But what's particularly exciting about it is that it has organic material in it, so a number of people believe that Titan might be a prebiotic planet - which means you have chemistry on it, but biology has not yet started. So Titan can give us a glimpse on possibly what our planet might have looked like a few billion years ago before biology started. In that sense it might even tell us what our roots are and how we came about. At the same time you're being a scientist, you are also, of course, the director of JPL. Can you tell us -- what does a lab director do? How does one lead hundreds of people? I think one of the key roles in the leadership of a place like JPL or other NASA centers is basically to lay out the vision of where the lab is heading -- what kinds of things we should be doing in the future, and to create an environment that allows the teams assigned to these missions to succeed and to excel. Because, in the end, it's a team effort. These missions don't happen because of one individual. They happen because a team of people who get the right leadership, the intellectual people who go after the missions, the dreams, and make sure these things happen. Our missions are literally the result of hundreds and thousands of people. On Cassini, probably at certain times, there were 800 to 900 people working on the mission. So my role is to provide the vision of where we are heading and then create an environment for people to excel - and then get out of their way. Much like being a head coach of a professional sports team? That's one way you can think about it. In still another capacity, you have recently been appointed the NASA Director of Advanced Planning -- what does that entail? The administrator Sean O'Keefe asked me to help the agency with laying out the long-term strategic planning -- how do we achieve the objectives that NASA has laid out for the next couple of decades, and to facilitate the development of roadmaps -- the options and different possibilities of how to achieve those goals. We do that groundwork with the broad community and then we bring those options in the form of roadmaps to the senior management at NASA to decide where do we go? In a sense, it's kind of putting in front of the NASA executive council -- what we call the Strategic Planning Council that O'Keefe has formed -- all the different possibilities and different approaches, the pros and the cons of the different approaches, and the investments that need to be made to achieve the different approaches. That way, the senior management of NASA has in front of them all the different possibilities brought up by the broad community. And this includes both human missions as well as robotic? Yes, that is correct. The Advanced Planning objective is simply trying to achieve NASA's vision and the nation's vision and that includes human, robotic, and scientific explorations. All of these will be part of the agenda to look at to see where we go from here. And where are we going? Can you give us any hints -- are we really going to the Moon? And is a manned mission to Mars truly in the offing? Absolutely. In the long term, we really need to get beyond Earth orbit. Humans must go beyond Earth orbit. To me, the first logical couple of steps are to go to the Moon and then go to Mars. The key question is -- how do we do that? How long will it take for us to do that? What is the homework and what are the technologies that need to be done in preparation for this? How fast we can do it will be -- like everything else -- budget and resources driven. What I like about the present vision of NASA -- and Sean O'Keefe has said it many times -- is the perspective that this is not like the Apollo space race, where we are trying to beat somebody else. This is a journey. Or, another way of putting it -- this is a commitment by our nation to do space exploration for the indefinite future. I liken it to the time after Lewis & Clarke did their first expedition to the West, when there was a commitment to expansion in the West. Then came the geologists and cartographers who mapped the West, and they were followed by the pioneers, and then by people like you and me. I envision space exploration as a similar kind of thing. This is a long-term commitment. The Westward expansionists did not say: 'We're going to populate the West by the year 1875, and we're going to spend $10 million dollars and if it's more than that then we're not going to go to the West.' What we're talking about here in this vision really is a long-term commitment to exploration. It makes perfect sense -- we are, after all, an exploring species. But I have to ask you, when you're not out there exploring Venus or Titan or developing a roadmap for future explorations, how do you unwind, relax in the midst of all these responsibilities? I'm sure your downtime is precious - how do you spend it? I live very close to the hills in Altadena, so I go fairly often hiking in the mountains, and I also do some dirt-biking -- Dirt-biking? Now that is an image -- I don't do it professionally -- and I don't wear all the gear. I just do it for the fun of it. Well, I do hope you wear a helmet? Yes, I do wear a helmet. Good to know. A brain like your needs protection. Usually, my biggest hobby is reading historic books. Right now I'm reading Heroes of History, by Will Durant. I just finished the personal log of Captain Cook. And, I also do some woodworking. We have an historic house, built by the western author Zane Grey, so I often do a lot of handiwork on the wood appointments. Your life is full indeed. On a very personal level, what makes the work worth it -- all the long hours, the heated science meetings, nail-biting moments, and all the challenges you confront day in, and year out, on the job -- what is it that keeps you coming back? One thing I tell every new employee who comes to JPL is this: If you are coming here for a job, you are in the wrong place. If you come here because you have passion for exploration, this is the right place. It's passion. I have been working at JPL for more than 30 years and I don't recall a single day where I didn't look forward to coming to work and I don't recall a single day when I didn't look forward to going home and telling my family what an exciting day I had and what fun new things we have done. It's that excitement -- the kid in me. I guess some of us never left our way of being a kid. But the kid is in many of us, each of us who says -- 'Wow, it's so fun to explore and find something new.' Nicely said. So what advice do you have for that young boy or girl -- in Lebanon or Canada or Cuba or France -- who is laying outside in his or her sleeping bag, watching the stars overhead, dreaming their dreams, maybe even of someday working for JPL? I tell them -- 'Dream and work hard for your dream' -- because everything is possible, particularly in a place like the United States -- if you put your mind to it, and you work hard at it, and you have passion for it. I tell people to nurture the passion they have, whatever it is that makes them really feel good or excited about living. Anything is possible if you put your mind to it. |
|||||
 |
 |
|||||
[ what is this? ]