About the Editors
Lucy-Ann McFaddenis a planetary scientist at the University of Maryland. She
was the founding director of the College Park Scholars Program, Science, Dis-
covery, and the Universe. She has published over 75 articles in refereed journals
and has been co-investigator on NASA’sNEAR,Deep Impact, andDawnmissions,
exploring asteroids and comets. McFadden has served on committees on solar sys-
tem exploration for the National Academy of Sciences and on the editorial board
ofIcarus.
Torrence V. Johnsonis a specialist on icy satellites in the solar system. He has
written over 130 papers for scientific journals. He received a Ph.D. in planetary
science from the California Institute of Technology and is now the Chief Scientist
for Solar System Explorations at the Jet Propulsion Laboratory. Johnson was the
Project Scientist for theGalileomission and is currently an investigator on the
Cassinimission. He is the recipient of two NASA Exceptional Scientific Achieve-
ment Medals and the NASA Outstanding Leadership Medal and has an honorary
doctorate from the University of Padua, where Galileo made his first observations
of the solar system.
Paul R. Weissmanis a Senior Research Sci-
entist at the Jet Propulsion Laboratory, spe-
cializing in comets. He is the author of over
100 scientific papers and 30 popular arti-
cles. He is also co-author, along with Alan
Harris, of a children’s book on theVoyager
mission. Dr. Weissman received his doctor-
ate in planetary and space physics from the
University of California, Los Angeles. His
work includes both theoretical and observa-
tional studies of comets, investigating their
orbital motion, their physical make-up, and
the threat they pose due to possible impacts
on the Earth. Dr. Weissman is an Interdisci-
plinary Scientist on ESA’sRosettamission to
comet Churyumov-Gerasimenko.
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