TheThe PLANETARYPLANETARY REPORT REPORT Volume XXV Number 2 March/April 2005 Huygens—Success! Volume XXV Table of Number 2 Contents March/April 2005 A PUBLICATION OF Features Basic Solar Sailing From 6 Solar sailing—how does it work? Society Vice President Bill Nye has a way The of explaining complex principles in fun, easy-to-understand ways. Here he takes on the basics of solar sailing, explaining to readers of all ages the physics behind this Editor novel propulsion method. e are waiting. We’ve been waiting 8 Eavesdropping on Huygens W 4 years. We are impatient. But this The Huygens probe was a great success, but, as with many successful space- is something truly worth waiting for. craft, it was not perfect. A problem with one of the probe’s radio links meant that What has us all standing around, champing data from the Doppler Wind Experiment had not been returned to Earth. Thanks to at the bit, on tenterhooks, and all those other the ingenuity of an international team of radio scientists, the experiment was saved. Sami Asmar, manager of the Jet Propulsion Laboratory’s Radio Science Systems clichés, is the launch of Cosmos 1, the first so- Group, tells the dramatic story. lar-sail spacecraft, on its mission to orbit Earth and demonstrate the feasibility of a technology A World Revealed: Huygens’ Images of Titan that could one day take us to the stars. 12 In January, the world watched as the Huygens probe returned our first-ever The only thing that makes the delays bear- views of Titan’s surface. Scientists are still examining the data, deciphering clues to able is knowing that we are doing what is nec- Titan’s past and present. Here, we present some of the most exciting pictures. essary to ensure the success of our mission. It’s a commonplace saying that a project can be Miranda: Shattering an Image done more quickly, less expensively, or better— 14 Uranus’ strange moon Miranda has been an object of intrigue since Voy - but you can’t have all three at the same time. ager 2 first returned close-up images of its haggard face in 1986. Now, nearly The “faster, cheaper, better” mantra of NASA, 20 years later, planetary scientist Bob Pappalardo shines new light on the tiny moon to our regret, did not prove doable. We faced and its fractured surface. precisely this situation with our solar sail. We are operating on a fixed budget, provided 20 Annual Report to Our Members by Cosmos Studios, Peter Lewis, and the mem- 2004 was an incredible year—with three spacecraft arriving at Mars and bers of The Planetary Society. We have allowed Cassini orbiting Saturn—and Society members were part of it all. For our members, improvements to our spacecraft to creep in, we have put together a short report on our activities and an overview of the Society’s knowing that each redundancy and upgrade financial status. increases our chances of success. The element we have let slide is schedule. Departments So we will not meet our published launch date. But all that stands in our way now are fi- 3 Members’ Dialogue nal tests of the assembled craft and scheduling the launch with the Russian navy, which will 4 We Make It Happen! send Cosmos 1 into orbit with a converted submarine-launched ballistic missile. We’re 19 World Watch within weeks of reaching our goal. Fingers Society News crossed! Good luck to us all! 22 —Charlene M. Anderson Contact Us On the Cover: Mailing Address: The Planetary Society, 65 North Catalina Avenue, Pasadena, CA 91106-2301 Top: As Huygens floated down through Titan’s atmosphere, it cap- General Calls: 626-793-5100 Sales Calls Only: 626-793-1675 tured these 30 images from altitudes of 13 to 8 kilometers (9 to 5 E-mail: [email protected] World Wide Web: http://planetary.org miles). Details are visible down to about 20 meters across, and the images cover an area 30 kilometers (about 19 miles) wide. 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). Dues in Bottom: A mountainous coastline marks the landscape near 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. Huygens’ landing site, as seen in this mosaic. Dark channels drain Editor, CHARLENE M. ANDERSON Copy Editor, A. J. SOBCZAK into a major river below. To terrestrial eyes, this looks like an aerial Associate Editor, DONNA ESCANDON STEVENS Proofreader, LOIS SMITH Managing Editor, JENNIFER VAUGHN Art Director, BARBARA S. SMITH photo of a scenic lakeshore, but on Titan, water behaves like rock Technical Editor, JAMES D. BURKE Science Editor, BRUCE BETTS Images: ESA/NASA/University of Arizona Viewpoints expressed in columns and editorials are those of the authors and do not necessarily represent positions of The Planetary Society, its officers, or its advisers. and hydrocarbons flow like water. ©2005 by The Planetary Society. Cofounder CARL SAGAN 1934–1996 Board of Directors Members’ Chairman of the Board NEIL deGRASSE TYSON Astrophysicist and Director, Hayden Planetarium, American Museum of Natural History Dialogue President WESLEY T. HUNTRESS JR. Director, Geophysical Laboratory, Carnegie Institution of Washington Vice President Titan on the Web and technology coordinator, deeply into these studies, they BILL NYE science educator We’re glad you liked our web Emily Lakdawalla, has provid- were unable to find any prac- Executive Director coverage of Huygens’ landing ed exciting “up-to-the-minute” tical mission possibility. LOUIS D. FRIEDMAN ANN DRUYAN on Titan from the European coverage of this historic event Of course, for interstellar author and producer DANIEL GERACI Space Agency’s European that is unmatched by anything sailing, we are probably a cen- Executive Vice President, Phoenix Companies LAURIE LESHIN Space Operations Center in I have seen and read on the tury or more away from being planetary scientist JOHN M. LOGSDON Darmstadt, Germany. Here Web to date. able to develop the kind of laser Director, Space Policy Institute, are a few of the comments we —RON LOCKWOOD, power that will be required for George Washington University Advisory Council Chair CHRISTOPHER P. McKAY received through planetary.org. Cape Town, South Africa practical flight. planetary scientist, NASA Ames Research Center —Louis D. Friedman, BRUCE MURRAY Professor of Planetary Science and Geology, Congratulations to all the Interstellar Flight Executive Director California Institute of Technology ELON MUSK many thousands of dedicated Technology Chairman, CEO, SpaceX JOSEPH RYAN people who have made this age In “Cosmos 1: The Journey Proper Credit Executive Vice President and of wonder and excitement a re- Begins” (see the November/ How could I not agree with General Counsel, Marriott International ROALD Z. SAGDEEV former Director, Institute for Space Research, ality. More to the point, thank December 2004 issue of The your reader James S. Veldman Russian Academy of Sciences YOU! Planetary Report), the authors (see the January/February STEVEN SPIELBERG director and producer I was ten years old when state that the solar sail is the 2005 issue) regarding human MARIA T. ZUBER Sputnik was the wonder of the only technology that may take spaceflight—especially when Professor, Massachusetts Institute of Technology world. That I have lived to see us to the stars. he says: “there is a window of Advisory Council JIHEI AKITA images of so many of my Back in the 1970s or 1980s, opportunity for going into Executive Director, The Planetary Society, Japan BUZZ ALDRIN neighbors in the solar system there was a feasibility study space, and that window will Apollo 11 astronaut NORTON BELKNAP knocks me out! called “Project Daedalus,” not remain open indefinitely.” President, Paul Taylor Dance Company RICHARD BERENDZEN Thanks again to all those which determined that a However, for the sake of educator and astrophysicist around the world who made fusion-powered ship (robotic) accuracy, may I point out that JACQUES BLAMONT Chief Scientist, Centre National d'Etudes Spatiales, France this possible. I’m proud to be was capable of exploring it was not Sir Patrick Moore RAY BRADBURY a member of The Planetary Sirius. Travel time was about who wrote the words in our poet and author DAVID BRIN Society and, when we show 12 years. The ship used pulsed foreword (from which this was author FRANKLIN CHANG-DIAZ this side of our nature, of the microfusion explosions as a paraphrased) but myself. Mr NASA, Astronaut Office ARTHUR C. CLARKE human race. propellant. Veldman refers to “his [Moore’s] author FRANK DRAKE —THOMAS JORDAN, No doubt, solar sails are recent book FUTURES,” but President, SETI Institute; Professor of Astronomy and As- Englewood, New Jersey far more financially probable the full title is: FUTURES: trophysics, University of California,Santa Cruz OWEN GARRIOTT former astronaut; Professor, than ships of the type described 50 Years in Space by David University of Alabama, Huntsville Emily Lakdawalla’s reporting by Daedalus. However, that A. Hardy and Patrick Moore. GARRY E. HUNT space scientist, United Kingdom from Germany is simply technology was investigated The book celebrates the 50 BRUCE JAKOSKY wonderful! Her firsthand re- several decades ago and years since Patrick and I first planetary scientist THOMAS D. JONES ports from the press con- determined to be possible— collaborated. planetary scientist, former astronaut, and author SERGEI KAPITSA ferences have given us all just very expensive. Speaking of anniversaries, Institute for Physical Problems, Russian Academy of Sciences an insight into what goes on —FABIAN STRETTON, may I offer my congratulations CHARLES E.