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Comet Team Biographies


Dr. John T. Clarke

Dr. John Clarke is a research professor in the Space Physics Research Laboratory at the University of Michigan. He received his undergraduate degree in physics from Denison University, and his master's and doctorate in physics from The Johns Hopkins University. Prior to joining the University of Michigan in 1987, he held a research position at the University of California, Berkeley, served as Associate Project Scientist on the Hubble Space Telescope project at NASA Marshall Space Flight Center, and was Advanced Instruments Scientist on the Hubble Space Telescope project at NASA Goddard Space Flight Center. At Johns Hopkins he was awarded a Forbush fellowship in 1980. He was recognized for Scientific Achievement at Goddard Space Flight Center in 1986.

Dr. Clarke's observes planetary atmospheres using a combination of the International Ultraviolet Explorer, Hubble Space Telescope (HST), and a sounding rocket experiment for which he is principal investigator. He has been named principal investigator on nine observing programs with the HST over the first four years of operation. He is a member of the team of scientists who developed the replacement Wide Fields Planetary Camera installed in the HST in December 1993 to repair the initial focusing error. He is currently using the new camera to image the planets at far-ultraviolet wavelengths as part of the team science program. He is the author of more than 50 research papers in professional journals.

Dr. Heidi B. Hammel

Dr. Heidi B. Hammel is a Principal Research Scientist at the Massachusetts Institute of Technology Department of Earth, Atmospheric, and Planetary Sciences, in Cambridge, Massachusetts. She received her undergraduate degree from the same department, and got her Ph. D. in Physics and Astronomy from the University of Hawaii in Manoa. Dr. Hammel works primarily in the field of outer planets and their satellites, with a focus on observational techniques. She is an acknowledged expert about the planet Neptune, and was a member of the Imaging Science Team for the Voyager 2 encounter with that planet. For the upcoming impact of Comet Shoemaker-Levy 9 into Jupiter, Dr. Hammel is leading the Hubble Space Telescope team that will investigate Jupiter's atmospheric response to the collisions. She is also a member of the team using NASA's Infrared Telescope Facility on Mauna Kea, Hawaii, and is part of an effort to obtain complete coverage of the impact event using small portable CCD systems deployed around the world.

David H. Levy

David H. Levy is an amateur astronomer and author. He has discovered 21 comets since 1984-eight from his own backyard and 13 others as a member of the Shoemaker-Levy observing team using the 1.2-meter Schmidt telescope at Mt. Palomar in California. He is the author of 11 books, including "The Quest for Comets" (Plenum, 1994) and "Skywatching" (The Nature Company, 1994). He is an instructional specialist with the University of Arizona's Project ARTIST, a program designed to bring astronomy into the elementary schools of Arizona.

Dr. Lucy McFadden

Dr. Lucy McFadden is currently a National Science Foundation, Visiting Professor at the University of Maryland, College Park, MD. She is visiting from the California Space Institute, University of California, San Diego. She received her undergraduate degree from Hampshire College, Amherst, MA, MS from the Department of Earth & Planetary Sciences, Massachusetts Institute of Technology, and a PhD in Geology & Geophysics from University of Hawaii. Dr. McFadden has investigated the surface composition of small bodies in the solar system and studies the compositional relationship between asteroids and comet nuclei. She has served on the National Research Council's Committees on Data Management and Computation (CODMAC), and Planetary and Lunar Exploration (COMPLEX), NASA's Small Bodies Science Working Group, and currently serves on the editorial board of ICARUS, the International Journal of Solar System Research. Dr. McFadden has co-authored over 30 research papers in refereed publications. She is currently Co-coordinator of the World-wide effort to observe Comet Shoemaker-Levy 9's collision with Jupiter which operates out of the University of Maryland's Department of Astronomy.

Dr. Melissa McGrath

Dr. Melissa McGrath is currently an Assistant Astronomer at the Space Telescope Science Institute in Baltimore, Maryland. She received her BA in Physics & Astronomy from Mt. Holyoke College in 1977, her MA in Astronomy from the University of Virginia in 1984, and her PhD in Astronomy from the University of Virginia in 1987. Her research is focused primarily on imaging and spectroscopic studies of the upper atmospheres of the outer planets Jupiter, Saturn, Uranus and Neptune, the Io and Titan atmospheres, and the Io plasma torus. She is the principal investigator on numerous space-based observing programs with the Hubble Space Telescope and the International Ultraviolet Explorer satellite as well as several ground-based observing programs.

Dr. Keith Noll

Dr. Keith Noll is an astronomer at the Space Telescope Science Institute in Baltimore, Maryland. He received his undergraduate physics degree, summa cum laude, from Saint Joseph's University in Philadelphia, a master's degree in physics from the University of Illinois, Urbana-Champaign, and a doctorate in astronomy from the State University of New York at Stony Brook. Before coming to the Space Telescope Science Institute in 1991, Dr. Noll held a postdoctoral position at the University of Arizona and was a National Research Council Fellow at NASA Marshall Space Flight Center in Huntsville, Alabama. Dr. Noll's chief research interests are the composition, formation, and evolution of the atmospheres and surfaces of planets. He is principal investigator on numerous observational projects using the Hubble Space Telescope and two telescope atop Mauna Kea, Hawaii, the NASA Infrared Telescope Facility and the United Kingdom Infrared Telescope. Dr. Noll also heads the solar system observations group at the Space Telescope Science Institute. He has published more than 40 research papers and abstracts in scientific journals and his work has appeared in The Planetary Report and Sky and Telescope magazines.

Dr. Carolyn S. Shoemaker

Since 1980, Dr. Shoemaker has served as a visiting scientist in the Astrogeology Branch of the US Geological Survey. In 1989, she became a Research Professor of Astronomy at Northern Arizona University, and in 1993 joined the staff of the Lowell Observatory. From 1981-1985, she served as a research assistant at the California Institute of Technology.

Dr. Shoemaker has discovered 32 comets, including 15 short period comets of the Jupiter family and 17 long period comets, two of which are giant comets that were difficult to discover because they get no closer to the sun than outside Jupiter's orbit. Working with her husband, Dr. Eugene Shoemaker, and David Levy, Dr. Shoemaker discovered periodic comet Shoemaker-Levy 9 in orbit around Jupiter in March 1993.

A prolific observer, Dr. Shoemaker is responsible for discovering more than 300 asteroids, of which 150 are numbered. Among the newly discovered asteroids are 40 Earth-approaching asteroids. She also developed an efficient stereoscopic technique for scanning films taken with Palomar Observatory's 46-cm Schmidt camera, the camera used to discover Comet Shoemaker-Levy 9, making it twice as fast to image the sky.

Since 1984, Dr. Shoemaker has worked in collaboration with her husband to investigate meteorite craters and ancient impact structures in Australia. She discovered the meteorites at Veevers crater and impactites at Wolfe Creek crater.

Dr. Shoemaker received her bachelor's and master's degrees from Chico State College in California. She received an honorary doctorate of science from Northern Arizona University in 1990. With her husband, she received the Rittenhouse Medal in 1988 and became a Cloos Scholar at Johns Hopkins University in 1990.

Dr. Eugene Shoemaker

Dr. Eugene Shoemaker is a scientist emeritus at the U.S. Geological Survey (U.S.G.S.), Flagstaff, Ariz., and a staff member at the Lowell Observatory in Flagstaff.

Dr. Shoemaker is a member of the three-person team (along with his wife Carolyn and amateur comet hunter David Levy) that discovered the comet that will impact Jupiter, as part of a monthly asteroid and comet survey at the Mt. Palomar Observatory. He also is the science team leader for the Clementine Deep Space Program Science Experiment that recently mapped the Moon.

Dr. Shoemaker is an expert in the mechanics of meteorite impacts and other large-body impact processes, and he was heavily involved in planning and conducting the lunar science accomplished during the Ranger, Surveyor and Apollo programs. He has been a geologist with the U.S.G.S. since 1948, but also has been associated with the California Institute of Technology and NASA. Dr. Shoemaker is a member of the National Academy of Sciences and has received numerous awards during his career, including the NASA Medal for Scientific Achievement and the National Medal of Science.

Dr. Harold Weaver

Dr. Hal Weaver is an astronomer at the Space Telescope Science Institute in Baltimore, Maryland. He received his doctorate in physics from The Johns Hopkins University in 1982. He was a resident research associate of the National Research Council working at the NASA Goddard Space Flight Center from 1982-1984. From 1984-1986, he served as an assistant project scientist on the Hopkins Ultraviolet Telescope (HUT) program, which is a shuttle-based astronomy mission. In July 1986, he joined the Space Telescope Science Institute, where he remains today.

Weaver's principal area of expertise is cometary science, which he has been pursuing since 1979. His thesis work involved analysis of cometary spectra obtained with the International Ultraviolet Observer (IUE) satellite. In 1985-1986, he performed infrared observations of Comet Halley from the Kuiper Airborne Observatory (KAO), which resulted in the first direct detection of water in comets. For this discovery, he was awarded the NASA Medal for Exceptional Scientific Achievement in 1988. Lately, his research has centered on HST observations of comets, and he is the principal investigator on the HST program to study Periodic Comet Shoemaker-Levy 9, which will plunge into Jupiter's atmosphere in July 1994.

Dr. Robert West

Dr. Robert West is a member of the technical staff of the Jet Propulsion Laboratory, California Institute of Technology (Caltech) in Pasadena. He received his undergraduate degree in Astronomy from Caltech, and his doctorate in Planetary Sciences from the University of Arizona. Prior to joining the Jet Propulsion Lab he was a Research Associate at the Laboratory for Atmospheric and Space Physics of the University of Colorado, Boulder. Dr. West's research focuses on the properties of cloud and haze particles in planetary atmospheres, and on radiative heating and circulation models for the stratospheres of the giant planets. He is a co-investigator on the Ultraviolet Spectrometer team for the Galileo mission. He is a team member on the Cassini Imaging team and a co-investigator on two other Cassini instruments (the Ultraviolet Imaging Spectrometer on the orbiter and the Descent Imager Spectro-Radiometer on the Huygens probe which will land on Titan). He is a Principal Investigator for a Hubble Space Telescope effort to observe the effects of comet Shoemaker-Levy 9 on Jupiter's stratosphere. He also is involved with the Earth Observing System MISR (Multi-angle Imaging Spectro-Radiometer) team. He is the author of numerous publications in professional journals and co-editor of a NASA book on time-variability in the Jovian system.

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