MEDIA RELATIONS OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIF. 91109. TELEPHONE (818) 354-5011
http://www.jpl.nasa.gov
Contact: Jane Platt
FOR IMMEDIATE RELEASE
March 5, 1998
JPL RECRUITS TWO EXPERTS TO HELP HUNT FOR NEW PLANETS AND LIFE
Two newly-arrived scientists at NASA's Jet Propulsion
Laboratory will play a key role in the search for planets around
other stars and the hunt for life beyond Earth. The appointments
highlight a new JPL initiative to unite scientists from various
disciplines, such as biology and astronomy, to study the
evolution of planets and life in the universe.
Dr. Didier Queloz, a Swiss astronomer who co-discovered the
first known planet around a star similar to our Sun, is a
distinguished visiting scientist at JPL for the next year and a
half. Dr. Kenneth Nealson has joined JPL as a senior researcher
in astrobiology, a new field whose goal is to understand how
planets and life co-evolve.
While at JPL, Queloz will continue his search for planets
and help the Lab develop sophisticated search technologies. His
work will benefit NASA's Origins Program, a series of planned
missions to study the formation of galaxies, stars, planets and
life. The program has gained momentum from discoveries by Queloz
and, subsequently, other astronomers, of several planets orbiting
stars beyond our Sun. Many scientists believe this raises the
odds that an Earth-like planet exists with suitable conditions
for life.
Queloz, a Swiss citizen, received his degree in physics in
1990 from the University of Geneva and worked on his doctoral
thesis at Geneva Observatory with Professor Michel Mayor from
1991 to 1995. Using the French Elodie telescope in Haute
Provence, France, they looked for signs of a Doppler shift in
nearby stars. As a star moves closer and then farther away from
Earth, the star's color shifts from red to blue. By detecting
this motion, astronomers can infer that the star is being tugged
by gravity from an orbiting planet.
"Back then, these experiments were considered a bit nutty,"
recalled Queloz. When Queloz and Mayor first detected a Doppler
shift from the star 51 Pegasus, Queloz said their first reaction
was, "We'd better check our instruments."
Even after they verified the instruments' accuracy, Queloz
and Mayor spent several weeks monitoring 51 Pegasus to confirm
the discovery. In July of 1995, they were confident enough to
buy a large cake and hold a celebration party in the south of
France for family and friends. Queloz and Mayor formally
announced their discovery, a Jupiter-sized planet orbiting 51
Pegasus, at an October 1995 scientific meeting in Florence,
Italy.
Queloz has received several honors, including the Swiss
Society for Physics' Balzers Award, the Bioastronomy Medal from
the International Astronomical Union, Commission 51, and a Best
Thesis in Science honor from a Swiss corporation, Vacheron
Constantin.
Queloz is continuing his hunt for new planets with the
Elodie telescope and its twin, Coralie, a Swiss telescope in La
Silla, Chile. But he and other astronomers face great challenges
in finding new and better ways to detect planets more like Earth.
Current techniques allow only for the detection of giant,
Jupiter-sized planets, which are considered unlikely candidates
for life.
While at JPL, Queloz will share his planet-finding
experience with engineers who are designing more advanced
technologies. Queloz is using a testbed interferometer at
Caltech's Palomar Observatory to run tests on stars and prepare
for an observing program. This work will help pave the way for
other Origins projects, including the W.M. Keck Observatory
interferometer in Hawaii, the Space Interferometry Mission, and
the Terrestrial Planet Finder, all being planned by NASA.
Interferometry combines and processes light from several
telescopes to simulate a much larger telescope, and holds great
promise as a tool in the search for Earth-sized planets. "I'd
like to play a role in future exploration by helping to define
interferometry techniques," Queloz said.
During his stay at JPL, Queloz is living in Pasadena with
his wife and their two children.
Until very recently, an astronomer like Queloz would have
had little if any interaction with a biological scientist like
Dr. Kenneth Nealson. But various disciplines, such as astronomy,
geology, biology and chemistry, are joining forces to study the
development of life on Earth and the prospects of life elsewhere.
Therefore, the work of scientists like Nealson and Queloz is
converging to form a broad, interdisciplinary approach.
"After all," said Nealson, "life is not a simple system and
no science operates in a vacuum. Younger students are studying
several disciplines to gain a more comprehensive view."
Nealson is part of this new wave of scientific training, as
a geobiology teacher and faculty associate in Caltech's geology
and planetary sciences division. At JPL, a division of Caltech,
Nealson has been appointed to head a new astrobiology unit.
Nealson said over the next few years, his astrobiology group will
develop an understanding of the way life and planets have
evolved, and will define the signatures of life.
"Not many foolhardy souls have ventured into this area,"
Nealson said. "After all, how can you find life if you don't
know what you're looking for? This is a very, very important
problem to be solved because right now we're not sure how to
distinguish life from non-life. Our goal is to develop tools to
make that distinction clearly."
In recent years, microbiologists have made startling
discoveries about the hardiness of life on Earth, studying living
organisms in thermal vents, acid lakes and other unlikely
environments. Nealson pointed out, "This has opened the eyes of
scientists to the notion that life could exist under seemingly
inhospitable conditions on other planets."
Astrobiologists will also study changes in Earth's chemical
composition over billions of years. They will then apply this
knowledge to other planets to look for "chemical signatures" that
might indicate that life has existed or could exist there.
Nealson said astrobiology will be useful for numerous space
missions, including the Mars sample return mission, scheduled to
bring back Martian rocks in the middle of the next decade.
Astrobiology will also benefit the Origins Program's Terrestrial
Planet Finder, which will look for Earth-like planets around
other stars and hunt for signs of life-sustaining chemicals.
Nealson said astrobiological studies may prove valuable in the
study of Jupiter's moon, Europa, which may have liquid oceans
under its frozen surface. This icy moon is currently being
studied by NASA's Galileo Europa Mission, and a new Europa
Orbiter has a planned launch in 2003.
Originally from West Liberty, Iowa, Nealson got his bachelor
of science degree in biochemistry in 1965 from the University of
Chicago. He earned his Ph.D. in microbiology from the University
of Chicago and did postdoctoral studies at Harvard University.
Nealson taught at Scripps Institution of Oceanography, San Diego,
CA, and at the Center for Great Lakes Studies, University of
Wisconsin, Milwaukee, WI. His honors include the Guggenheim
Fellowship for Sabbatical Leave in 1981, and an appointment as an
elected fellow in the American Academy of Microbiology, which he
received in November 1993.
Nealson and his wife live in South Pasadena, CA.
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