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The PLANETARY REPORT The PLANETARYPLANETARY REPORT REPORT Volume XXII Number 4 July/August 2002 Radar “Eyes” Volume XXII Table of Number 4 Contents July/August 2002 A PUBLICATION OF Features From The The Mars Odyssey Continues 4 In May, the Mars Odyssey mission team announced that the spacecraft’s Editor Gamma Ray Spectrometer (GRS) had detected large amounts of hydrogen— inferred as water-ice—around Mars’ south pole. The Society’s director of projects, he news services have given consid- Bruce Betts, has been following Mars Odyssey since it entered Mars orbit last fall. Terable time lately to space science Here, Bruce continues his coverage, examining the GRS results and updating us discoveries: an asteroid passes close by on the mission’s progress. Earth; vast quantities of water lie just beneath the Martian surface; a planetary 8 Extra! Extra! Read All About It: system similar to ours orbits a nearby Extrasolar Planets on the Rise! star. In this issue, you’ll read about how Back in 1982, The Planetary Society began supporting searches for extrasolar plan- such discoveries advance our under- ets—we were among the first to grasp the potential significance of finding worlds standing of the worlds around us. like ours circling other stars. Projects we initiated—one led by George Gatewood The press realizes that space explo- at the Allegheny Observatory in Pittsburgh and another by Bruce Campbell at the ration can still excite the public. The pub- University of Victoria in British Columbia—advanced the field but made no con- lic still marvels at amazing discoveries. firmed discoveries. Since then, more than 60 Jupiter-size extrasolar worlds have But other concerns on the rapidly chang- been discovered. Now, we are sponsoring a new program at the Kitt Peak National ing radar of this planet can drive such Observatory. Project leader Steve Howell reports on its progress. enthusiasms to the bottom of priority lists, as we’ve seen reflected in opinion 14 Taking the Measure of Microworlds polls. The world has changed from the Asteroids are small, dark, distant, and, in general, hard to see. Even using supercharged days of the early space age, the most powerful optical telescopes, we observe them only as points of light or when we were ready to undertake any streaks against a star field. Scientists have, however, developed the means to render challenge any time, especially, to para- exact orbits and give shape to points of light: radar astronomy. Science writer phrase President John F. Kennedy, if it Robert Burnham reports on the discoveries of this little-known but highly produc- was hard. All space exploration is hard. tive technology. For us in The Planetary Society, this change in society as a whole presents a formidable challenge. It’s up to us to make Departments sure that the exploration of the solar system and search for extraterrestrial 3 Members’ Dialogue life receives the priority it deserves. In the coming months, we will call 7 World Watch upon you to join again in supporting Questions and Answers planetary exploration, through political 20 action and other means. As always, 22 Society News together we can make it happen. —Charlene M. Anderson Contact Us On the Cover: As the Sun dramatically drops from sight in California’s Mojave Mailing Address: The Planetary Society, 65 North Catalina Avenue, Pasadena, CA 91106-2301 Desert, Goldstone’s 70-meter antenna stands poised and General Calls: 626-793-5100 Sales Calls Only: 626-793-1675 ready for work. Part of NASA’s Deep Space Network—used to E-mail: [email protected] World Wide Web: http://planetary.org communicate with planetary spacecraft—Goldstone is one of the world’s two primary facilities set up for planetary radar as- The Planetary Report (ISSN 0736-3680) is published bimonthly at the editorial offices of The Planetary Society, 65 North Catalina Avenue, Pasadena, CA 91106- 2301, 626-793-5100. It is available to members of The Planetary Society. Annual dues in the US are $30 (US dollars); in Canada, $40 (Canadian dollars). tronomy. Scientists are using radar to peer into the dark re- Dues in other countries are $45 (US dollars). Printed in USA. Third-class postage at Pasadena, California, and at an additional mailing office. Canada Post Agreement Number 87424. gions of our solar system, discovering and tracking potentially Editor, CHARLENE M. ANDERSON Copy Editor, AMY SPITALNICK hazardous near-Earth asteroids. Associate Editor, DONNA ESCANDON STEVENS Proofreader, LOIS SMITH Managing Editor, JENNIFER VAUGHN Art Director, BARBARA S. SMITH Image: JPL/NASA Technical Editor, JAMES D. BURKE Technical Editor, BRUCE BETTS Viewpoints expressed in columns or editorials are those of the authors and do not necessarily represent positions of The Planetary Society, its officers, or advisers. ©2002 by The Planetary Society. Cofounder CARL SAGAN 1934–1996 Members’ Board of Directors Chairman of the Board BRUCE MURRAY Professor of Planetary Science and Geology, Dialogue California Institute of Technology President WESLEY T. HUNTRESS JR. Director, Geophysical Laboratory, Carnegie Institution of Washington Vice President A Long-Term Plan A Tribute to NEIL DE GRASSE TYSON maybe, an hour or more, but I’m Astrophysicist and Director, Hayden Planetarium, In my mind, “Whither, O Splen- honestly tongue-tied when it Stephen Jay Gould American Museum of Natural History Executive Director did Ship?” by James D. Burke comes to summing up this issue Leading paleontologist and LOUIS D. FRIEDMAN ANN DRUYAN and John Young (see the Jan- in 25 well-chosen words or less. evolutionary theorist Stephen author and producer uary/February 2002 issue of The —JAMES WALKER, Jay Gould passed away on May DONALD J. KUTYNA former Commander, US Space Command Planetary Report), addresses a Brasilia, Brazil 20, 2002. Neil de Grasse Tyson, JOHN M. LOGSDON Director, Space Policy Institute, larger problem: that to survive vice president of The Planetary George Washington University Advisory Council Chair as a species, we must come to We invite our members to respond Society and director of the CHRISTOPHER P. McKAY terms with our most serious evo- to Mr. Walker’s query. How would Hayden Planetarium at the planetary scientist, NASA Ames Research Center BILL NYE lutionary weaknesses. There are you get this important point American Museum of Natural science educator JOSEPH RYAN innumerable steps on the path to across—in 25 words or less? History in New York City, came Executive Vice President and attaining greatness as a space- —Charlene M. Anderson, Asso- to know Gould (a member of General Counsel, Marriott International ROALD Z. SAGDEEV former Director, Institute for Space Research, faring civilization. Accepting re- ciate Director the Society’s Advisory Council) Russian Academy of Sciences sponsibility as custodians of through his close association STEVEN SPIELBERG Earth counts as a first step. I want to thank The Planetary with the museum. Their popu- director and producer KATHRYN D. SULLIVAN President and CEO, Ohio’s Center Second, imagine if our race Society for the issues of The lar essays shared space within of Science and Industry and former astronaut drew as much satisfaction from Planetary Report discussing the the covers of Natural History MARIA T. ZUBER scientific research as from the strange acceleration of Pioneers magazine. Tyson wrote the Professor, Massachusetts Institute of Technology entertainment industry. I find it 10 and 11 (beginning with the following in memory of his Advisory Council JIHEI AKITA frustrating that technology pro- November/December 2001 issue). colleague: Executive Director, The Planetary Society, Japan BUZZ ALDRIN gresses most rapidly when there We at the NASA Ames Research “I feel lonely without Apollo 11 astronaut RICHARD BERENDZEN is a short-term materialistic goal Center Pioneer Mission office Stephen Jay Gould. Who educator and astrophysicist to be achieved. How is it that an have worked with the authors of would have thought, before he JACQUES BLAMONT Chief Scientist, intelligent species cannot recog- the article by providing data to landed on the pages of Natural Centre National d'Etudes Spatiales, France RAY BRADBURY nize that its very survival hinges aid their investigation of this History magazine, that essays poet and author on its ability to plan for the vexing anomaly. on science could be raised to a DAVID BRIN author “long run”? Since their launch, the Pio- form of art? The success of his FRANKLIN CHANG-DIAZ I concur with the authors that neer 10 and 11 missions—being efforts gave me confidence to NASA, Astronaut Office ARTHUR C. CLARKE education is vital. People must in the vanguard of space travel step onto this landscape with author FRANK DRAKE recognize the common sense of a and science investigation—have him. From 1995 through 2001, President, SETI Institute; Professor of Astronomy and Astrophysics, long-term strategy while obtain- captured the imagination of the each of our essays bookended University of California, Santa Cruz GARRY E. HUNT ing a passion for the future. space community. The plaque the central articles of the mag- space scientist, United Kingdom —JANE GOODHUE on Pioneer (the first emissary azine. We wrote, of course, on SERGEI KAPITSA Institute for Physical Problems, GILHOOY, into outer space) tells the story completely different subjects. Russian Academy of Sciences CHARLES E. KOHLHASE JR. Norfolk, Virginia of humanity’s presence on Earth But I continually felt a deep mission designer, author, digital artist around the last quarter of the kinship of mission—a mission
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