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The following interview occurred March 1, 1999, between Technical Staff Member in the Space and Atmospheric Science Division Roger Wiens, Los Alamos National Laboratory (LANL), and Senior Associate Alice Krueger, Mid-continent Regional Educational Laboratory:
A. K. Your work for the Genesis mission at LANL is as co-investigator and project lead. What do those two job titles mean?
R.W. Co-investigator means that I am one of the scientists who will be involved in the measurements and publication of the results when we get the samples back. Also we are advising on issues affecting the science prior to launch. As project lead at LANL I am in charge of all activities here including building three instruments for the payload. I make sure they are going to do what they are designed to do, and make sure they won't fail anywhere in flight.
A.K. What new science understanding will the Genesis mission provide? Why is this important?
R.W. The solar system was created four and a half billion years ago from a cloud of gas and dust. We know the dates of this from asteroids, pieces of which we have in the form of meteorites, and from moon rocks and our own Earth. We don't know the details of how the solar system was formed. Genesis is one of the few [NASA] missions that addresses that issue, only the other ones are astrophysics missions. The most familiar one is the Hubble Telescope. It shows us other star systems in the process of formation. To be specific, the sun contains more than 99% of the solar system material. Genesis should tell us something about the average composition of our solar system so we can compare the solar system composition with individual planets.
A.K. You are a physicist and many of the other scientists on this mission are chemists. How would you compare what is and is not known about the sun and solar wind in terms of physics and chemistry?
R.W. A fair amount is known of the physics of solar wind. We know its velocity, the charge state of ions in the solar wind, something about the acceleration processes near the sun, and about its interaction with magnetic fields like the Earth's. We know some about the chemical composition. It is about 92% hydrogen. Most of the rest is helium. Only a small part is elements we're familiar with from Earth-oxygen, nitrogen, carbon. We don't know much at all about the isotopic composition of solar wind. For chemists and geochemists, isotopic ratios are quite important.
A.K. You have a strong physics background, but you describe yourself as a geochemist. What is the difference between geochemistry and geophysics?
R.W. A geophysicist typically deals with seismology and stuff like that. Geochemistry is more what I do, study the chemistry of rocks and materials. Although I have a degree in physics, geochemistry is more fitting for what I do. I got my Ph.D. from a physics department doing geochemistry. I also studied (have a minor in) geology. I was using mass spectrometers that were developed for meteorites and moon rocks that were developed by physicists in that department.
A.K. You have been a visiting scientist at two US institutions and at a University in Switzerland. What is a visiting scientist? How did you become one?
R.W. While I was on staff at Caltech, I was interested in using techniques that were available elsewhere. I took samples to Argonne National Laboratory and worked there for a number of two to three week periods. They had the facilities and equipment. It was a similar thing with Switzerland. They had the facilities to test a prototype solar wind concentrator. We built it at Caltech, then tested it in Switzerland, then analyzed the data back at Caltech. We got several gigabytes of results, which were transferred over the Atlantic by Internet. I also worked at Johnson Space Center during my graduate school days. At Argonne, being a visiting scientist was an official title, the main advantage of which was to avoid having to go through the health and safety requirements again every nine months or so when I went out there. At the other places, this was an unofficial title. These types of collaborations can be very useful because one gets to know in detail a different experimental technique, and one also gets to know quite well the different scientists at the respective institutions. However, working away from home can be more expensive, and can keep you away from your family and friends.
A.K. You are co-investigator for three other projects in addition to your Genesis work. How do you do that work and the Genesis work? What else do you do at LANL and elsewhere?
R.W. Almost all of my work now is on Genesis. There are several other projects I am involved in that have interesting instruments. One of them will hopefully be on a future Mars mission. It can determine the composition of a rock from some distance away. It uses a really small laser the size of your index finger that can actually run on a nine volt transistor battery. It emits a very short light pulse, which hits the rock. That gives a little POW and a spark of light on the rock. Instruments back on the other side of the room analyze the composition of the rock [by analyzing the light given off]. The laser analysis tool can cover a bigger area than the Pathfinder Rover covered. It just needs to sit there on the lander, though it could also help a rover reach inaccessible areas. These other projects are in the development stage, where Genesis was five years ago. We are always looking for new things to do. I am also involved in data analysis from DS-1. [NASA's first deep space validation flight in the New Millennium Program, is an asteroid/comet flyby mission which was launched in 1998.]
A.K. What is your everyday work life like?
R.W. Overall I spend about 40 hours per week on Genesis. Another 10 hours are spread between other things. For instance, this morning I biked in and got here about 7:30. Then I checked my email messages, then checked on a computer simulation I had run over the weekend. Typically I have some appointments. In a typical day I'll spend an hour on the phone with other project members. Often it is a conference call. I check with the instrument leads [Bruce Barraclough and Beth Nordholt, in charge of the monitors and concentrator, respectively] on specific details regarding the instruments. Then I run around and see how the technicians are doing. There are several design engineers who put our design ideas on paper, and mechanical technicians who assemble the instruments and test apparatus. These people have very important jobs. Perhaps I'll do some computer simulation runs or take some data to calibrate or test an instrument.
A.K. Are there any barriers to your work at the present time?
R.W. Politics and administrative oversight are significant barriers. No one likes what they may consider excessive oversight on their projects. But of course, oversight is necessary. The politics involved in getting on a project is the most challenging aspect of all. One would like to think that the best and most economical instruments get chosen for space missions, but that's not the real world. There's a lot of politics involved.
A.K. What kind of education and career path led you to become a scientist?
R.W. I have always been interested in science. My brother and I grew up building and launching model rockets. We built a telescope and did some astronomy. I went to college and majored in science, but I didn't know where I would end up. There are other important things in life. I thought I might be an engineer but physics was the most challenging, so I stayed with it. I was wowed by a potential thesis advisor who would let me analyze meteorites. He warned me that there were not terribly many jobs. At that time I thought I would go into teaching. By Providence, I never got to teach. I did postdoctoral research after graduate school. I studied rocks from the bottom of the ocean and hot spots like Hawaii. I wanted to find out what the Earth's mantle was like. The last nine years I have spent working on what became the Genesis mission with Don Burnett.
A.K. What is postdoctoral research? Why is doing postdoctoral research important to a scientist's career?
R.W. It is typically a short-term position, lasting about two years. It is done right after getting your Ph.D. Typically in the old days you became a professor right after graduation. These days the job market often doesn't support that. You work a few places, not in the same place all your life. Different people have different outlooks, they study different aspects of things. If you are studying meteorites, you may start with studying their chemical composition, then do a postdoc stint studying their mineralogical composition. That's a rather simplistic example. For my Ph.D. thesis I studied noble gases-helium, neon, argon, krypton, xenon-in Martian meteorites. Then I wanted to study these elements in the interior of the Earth. It is slightly related, but not totally related. If you understand the noble gas composition of Martian meteorites, you can understand something of how the interior of Mars has been processed. You can study noble gases coming from rocks in mid-ocean ridges or volcanic hot spots like Hawaii to see what it's like inside the Earth and how it has changed over time. For argon, radioactive daughter products are added to crustal material but not those in the mantle. By comparing, you can find out two things: the original composition of noble gases in the Earth and how it changed, and what processes changed. There are many other interesting details.
A.K. What is your family life like? What are your leisure time activities?
R.W. I am married and have two preschool boys. I try to spend as much time with them as I can. Both of them are daddy's boys. At home, wherever I am, the two boys are around me too. There is always competition between work and family. We like to hike and swim. I am involved in our church. I find time to be alone with my wife too. I have to budget it in.
A.K. What kind of advice would you give to young science students?
R.W. It is important to find the right people to study under. Keep trying to do what you want to do. Keep asking questions- especially the big questions. How did we get here? Why are we here?
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