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John Spencer

John Spencer is a Staff Scientist at Southwest Research Institute's Department of Space Studies in Boulder, Colorado. A native of England, he obtained a Bachelor's degree in Geology from the University of Cambridge in 1978, and got his PhD in Planetary Sciences from the University of Arizona in 1987. He spent four years in postdoctoral positions at the University of Hawaii before joining the staff of Lowell Observatory in Flagstaff, Arizona, in 1991. He worked there till he joined Southwest Research Institute in January 2004.

He specializes in studies of the moons of the outer planets, particularly the four large "Galilean" satellites of Jupiter, using theoretical models, Earth-based telescopes, close-up spacecraft observations, and the Hubble Space Telescope. He was responsible for temperature mapping of Jupiter's moons with the Photopolarimeter-Radiometer (PPR) instrument on the Jupiter-orbiting Galileo spacecraft, and is now assisting in the mapping of temperatures on Saturn's moons using the Composite Infrared Spectrometer (CIRS) on the Cassini Saturn orbiter. He is particularly interested in the active volcanos and atmosphere of Jupiter's moon Io, and more recently in the active ice eruptions of Saturn's moon Enceladus. He has also published research on Mars, asteroids, Pluto, and Neptune's moon Triton, and is a science team member on the New Horizons mission to Pluto and the Kuiper belt.

His observational work has included discovery of several major volcanic eruptions on Io, the first observations of Io's volcanic plumes with the Hubble Space Telescope; discovery of sulfur gas in Io's plumes; co-discovery that Io's atmosphere is highly asymmetrical; co-discovery of ice volcanic activity on Saturn's moon Enceladus; and co-discovery of oxygen on Jupiter's moon Ganymede. His theoretical work has improved our understanding of nitrogen frost on Pluto and Triton, water frost on Jupiter's moons, and heat radiation from asteroids.

Steve Squyres

Steven Squyres' research focuses on the large solid bodies of the solar system: the terrestrial planets and the satellites of the Jovian planets. His work involves analysis of data from both spacecraft and ground-based telescopes, as well as a variety of types of geophysical modeling. Areas of particular interest include the tectonics of Venus, the history of water on Mars, and the geophysics of the icy satellites of the outer planets. Data analysis and theory are used together to examine the processes that have shaped the surfaces and interiors of these bodies.

Squyres has participated in a number of planetary spaceflight missions. From 1978 to 1981 he was an associate of the Voyager imaging science team, participating in analysis of imaging data from the encounters with Jupiter and Saturn. He was a radar investigator on the Magellan mission to Venus, a member of the Mars Observer gamma-ray spectrometer flight investigation team, and a co-investigator on the Russian Mars `96 mission. Dr. Squyres is currently the scientific Principal Investigator for the Mars Exploration Rover Project. He is also a co-investigator on the Mars Express mission, and on the Mars Reconnaissance Orbiter's High Resolution Imaging Science Experiment. He is a member of the Gamma-Ray Spectrometer Flight Investigation Team for the Mars Odyssey mission, and a member of the imaging team for the Cassini mission to Saturn.

Peter Smith

Peter Smith graduated in 1969 from the University of California Berkeley in physics and later continued his education at the University of Arizona Optical Sciences Center graduating with a master's degree in 1977.

Smith has been employed at the UA's Lunar and Planetary Laboratory since 1978, starting as a Research Assistant and progressing step-by-step to a Senior Research Scientist. During this period, Smith participated in many of the seminal space missions that have explored the solar system.

During the Pioneer Venus mission in 1978, Smith created models of the energy sources that heat the surface of Venus to nearly 1000 degrees. Pioneer Saturn, in 1979, initiated nearly a decade of study of outer-planet atmospheres, particularly for Jupiter and Titan. Mysterious, cloud-enshrouded Titan became the focus for Smith's research which led to observations and mapping of the solid surface of Titan, Saturn's largest moon, using the Hubble Space Telescope in 1994. Working with Dr. Martin Tomasko, Smith became the Project Manager for a descent camera for the Huygens mission to the surface of Titan that landed in early 2005 and returned the first close-up images of Titan's surface.

In 1993, Smith started his association with the Red Planet after his Imager for Mars Pathfinder camera proposal was accepted by NASA for the Pathfinder mission. As the first lander to reach Mars since the two Viking missions in 1976, there was tremendous public interest as the camera returned the first images from the Martian surface on July 4, 1997.
Day-by-day images of the alien landscape explored by the Sojourner Rover were featured on the front pages of newspapers and on the TV news networks. Since then Smith has built cameras for the Mars Polar Lander mission that crashed on the Martian surface in December 1999. Later, the 2001 Surveyor mission was cancelled because of the loss of Mars Polar Lander, grounding more UA-built cameras.

Despite these setbacks, Smith has continued to associate with Mars missions and is serving on the science team for the Mars Exploration Rovers that landed in January 2004. He also helped build the microscope for Beagle 2, a European lander that failed to return data upon its arrival to Mars in December 2003. Smith spent nearly two years managing the building of the 2005 Mars Reconnaissance Orbiter HiRISE camera for which Dr. Alfred McEwen of the UA is the Principal Investigator.

In fall 2003, after one and a half years of proposal development, Smith's Phoenix project was selected as the first Scout mission to Mars after a competitive NASA selection process. The Phoenix mission is valued at $420 million, and Smith is fully responsible for all aspects of the mission. The spacecraft launched August 4, 2007, and will land in the northern polar region of Mars on May 25, 2008. The lander will conduct science experiments for 3 to 5 months as part of NASA's search for life in our solar system. The Phoenix name recalls the mythological bird that rises from the ashes of his predecessor. The Phoenix mission uses the mothballed 2001 lander with instruments delivered for both that mission and the failed Polar Lander mission.

Chris McKay

Dr. Christopher P. McKay, Planetary Scientist with the Space Science Division of NASA Ames. Chris received his Ph.D. in AstroGeophysics from the University of Colorado in 1982 and has been a research scientist with the NASA Ames Research Center since that time. His current research focuses on the evolution of the solar system and the origin of life. He is also actively involved in planning for future Mars missions including human exploration. Chris been involved in research in Mars-like environments on Earth, traveling to the Antarctic dry valleys, Siberia, the Canadian Arctic, and the Atacama desert to study life in these Mars-like environments. His was a co-I on the Titan Huygen's probe in 2005, the Mars Phoenix lander misson for 2007, and the Mars Science Lander mission for 2009.

Lynn Rothschild

Co-Investigator - Responsible for the overall management of Investigation 6 – Planetary Pioneers, and participate in efforts to identify new model organisms, do the initial tests for UV and desiccation resistance, and mechanisms of resistance. Will also be involved in various EPO activities and co-organizing the Stanford Astrobiology and Space Exploration course.

Ben Clark

Dr. Benton C. Clark is Chief Scientist, Flight Systems, at Lockheed Martin Astronautics. He received his Ph.D. in Biophysics from Columbia University in 1968. He was responsible for conceiving and developing the x-ray fluorescence spectrometers used for geochemical analyses of Martian soil samples onboard the Viking landers. He was Co-I for development of the lightflash detector and sunshade for the Particle Impact Analyzer (PIA) experiment, flown successfully on the Giotto mission. He has introduced the concept of key roles for cometary particulates and formation of comet ponds as an enabling step for the abiotic origin of life. He chairs the External Advisory Committee for the NASA Center for Research and Training in Exobiology at the University of California San Diego and Salk Institute. He has received the NASA Public Service Medal, the Wright Brothers Award, the Air Force Service Medal, and has been selected Inventor of the Year for Martin Marietta Corporation and Author of the Year for Martin Marietta Astronautics.

Richard Zurek

Currently, Dr. Richard Zurek serves as the Chief Scientist for the Mars Program Office at JPL and continues as the Project Scientist for the Mars Reconnaissance Orbiter. MRO finished its two-year primary science phase in November 2008, but continues with an Extended Science Phase for another two years. As a researcher, Dr. Zurek has studied the upper atmosphere of the Earth and the atmosphere of Mars, using observational data acquired by spacecraft such as the Upper Atmosphere Research Satellite (UARS), Mariner 9, the Viking Orbiters and Landers and the current Mars operating missions.


Dr Scott Bolton

Dr. Scott Bolton, Principal Investigator for the Juno mission is based at the Southwest Research Institute's headquarters in San Antonio, Texas. He leads the large international team of Juno scientists who developed the scientific goals and implementation strategy for the mission. SwRI will conduct mission operations, and will manage the scientific team participation. SwRI is providing two instruments for Juno; the Ultraviolet Imaging Spectrometer and the Jupiter Auroral Distributions Experiment.

Robert Pappalardo

Robert Pappalardo is a Senior Research Scientist in the Planetary Ices Group, Science Division, of the Jet Propulsion Laboratory in Pasadena, California.
Pappalardo's research focuses on processes that have shaped the icy satellites of the outer solar system, especially Europa and the role of its probable subsurface ocean. Europa research includes the possibility that solid-state convection has played an important role in the satellite's history, investigation of regions of separation and spreading of the satellite's icy lithosphere, and implications of the surface geology for lithospheric properties and the existence of a liquid water ocean beneath the icy surface. Additional recent research involves the nature, origin, and evolution of bright grooved terrain on Jupiter's moon Ganymede, specifically the style of tectonism and implications for the satellite's geological history. Also, he is investigating the geological implications of geyser-like activity on Saturn's moon Enceladus.
In 1986 he received his B.A. in Geological Sciences from Cornell University, and in 1994 he obtained his Ph.D. in Geology from Arizona State University. As an affiliate member of the Galileo Imaging Team while a researcher at Brown University, he worked to plan many of the Galileo observations of Jupiter's icy Galilean satellites. From 2001-2006, he was an Assistant Professor of Planetary Sciences in the Astrophysical and Planetary Sciences Department of the University of Colorado at Boulder, and he continues to mentor graduate student researchers. Along the way, he has worked with various science museums and organizations to bring the excitement of astronomy and planetary exploration to the public.

Athena Coustenis

Born in Athens, Athena Coustenis is a Planetary scientist with French citizenship who currently works at the Paris-Meudon Observatory. She is heavily involved in the Cassini- Huygens mission to Saturn and Titan, and has used a variety of large telescopes to conduct planetary investigations.Paris-Meudon Observatory is the most important observatory in France. The facilities at Meudon include a 36-metre tall concrete tower containing a sophisticated spectrograph for examination of the Sun. Nearby, astronomers have converted the beautiful and luxurious Chateau de Meudon into an observatory and some have even lodged there!

Carolyn Porco

Planetary scientist Carolyn Porco studies and interprets the photos from the Cassini-Huygens mission, orbiting Saturn and its largest moon, Titan. She and a team of scientists from NASA and the European Space Agency have been analyzing the data that Cassini has been sending back since it left Earth in 1999. They've found many new rings and four new moons (so far). And they've produced breathtaking images and animations of the stormy face of Saturn, its busy rings, and its jumble of moons and moonlets.
Back in the mid-1980s, while still working on her doctorate, Porco was drafted onto a team at JPL that was crunching the mountains of data coming back from the Voyager fly-by of Saturn. Her work on the planet's "ringlets," and on a spoke pattern noticed in the rings, made an important connection between Saturn's rings and its magnetic field -- and cemented her connection with Saturn.


Heidi B. Hammel

Heidi B. Hammel joined The Planetary Society's Board of Directors in 2005. A Senior Research Scientist with the Space Science Institute in Boulder, Colorado, Hammel herself lives in Ridgefield, Connecticut.

She received her undergraduate degree from the Massachusetts Institute of Technology in 1982 and her Ph.D. in physics and astronomy from the University of Hawaii in 1988. After a post-doctoral position at the Jet Propulsion Laboratory (Pasadena, California), Hammel returned to MIT, where she spent nearly nine years as a Principal Research Scientist in the Department of Earth, Atmospheric, and Planetary Sciences.
Hammel primarily studies outer planets and their satellites, with a focus on observational techniques. For the impact of Comet Shoemaker-Levy 9 with Jupiter in July 1994, Hammel led the Hubble Space Telescope Team that investigated Jupiter's atmospheric response to the collisions. An expert on the planet Neptune, she was a member of the Imaging Science Team for the Voyager 2 encounter with the gas giant in 1989. Her latest research involves studies of Neptune and Uranus with Hubble and other Earth-based observatories. Hammel is also an Interdisciplinary Scientist for Hubble's successor, the James Webb Space Telescope, which is scheduled for launch in 2011.
Hammel received the 2002 American Astronomical Society's Division for Planetary Sciences (AAS/DPS) Sagan Medal for outstanding communication by an active planetary scientist to the general public.

Mark Showalter

Planetary astronomer Mark Showalter is rabid about rings. While everyone knows about Saturn’s spectacular ring system, it’s often forgotten that Jupiter, Uranus, and Neptune are also encircled by fainter and narrower rings. Each of these systems interacts closely with a family of small, inner moons. Showalter works on some of NASA’s highest-profile missions to the outer planets, including Cassini, now orbiting Saturn, and New Horizons, which recently flew past Jupiter en route to its 2015 encounter with Pluto. Known for his persistence in planetary image analysis, Mark’s work on the earlier Voyager mission led to his discovery of Jupiter’s faint, outer “gossamer” rings and Saturn’s tiny ring-moon, Pan.

Mark now splits his time between NASA space probes and Earth-based observing. He has been a frequent investigator with the Hubble Space Telescope. Since 2002, he has been leading a team of astronomers studying the planet Uranus. His discovery of two small moons and two faint rings orbiting that distant planet received national attention in 2006. He has also been visiting the 10-meter Keck Telescope facility in Hawaii, where the new Adaptive Optics system has begun to rival and sometimes surpass Hubble in the clarity of its images. He will soon be turning his attention further outward to Neptune, which is encircled by a peculiar family of rings, moons and incomplete arcs. These were studied by the Voyager.

Dr Andrew P. Ingersoll

Dr. Andrew P. Ingersoll, the Earle C. Anthony Professor of Planetary Science at the California Institute of Technology, is an expert on the weather and climate of Earth and the outer planets. He has been a science team member and/or interdisciplinary scientist for deep space missions including Pioneer Jupiter/Saturn, Pioneer Venus, Voyager, VEGA Venus Balloons, Mars Global Surveyor, Galileo, and Cassini.

Basically, Andy is a planetary meteorologist. Planetary meteorologists try to understand how atmospheres work, classifying their behavior, and developing numerical models to explain them. In terms of Neptune and Uranus Andy can talk right across temperatures, pressures, winds, clouds, and gaseous composition.




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