I I 1630-128 I MAGELLAN I I I I FINAL SCIENCE REPORTS I I October 22, 1993 I I I I. I I NATIONAL AERONAUTICS AND SPACE ADMINISTRATION JET PROPULSION LABORATORY I CALIFORNIA INSTITUTE OF TECHNOLOGY PASADENA, CALIFORNIA I I JPL D-11092 I I I I 1630-128 I MAGELLAN I I I FINAL SCIENCE REPORTS I I October 22, 1993 I I I I COMPILED BY I THOMAS W. THOMPSON SCIENCE AND MISSION PLANNING OFFICE I I Distribution: Magellan Investigators and Staff I NASA Magellan Program Office I JPL D-11092 I I I I I I I I I I I I I I I I I I I I I I I I MAGELLAN FINAL SCIENCE REPORTS I Table of Contents Executive Summary ......................................................................................... , ................. iii I Role Statements .................................................................................................................. iv I Reports Submitted by: Akim, E. L. Russian Academy of Sciences, Moscow ................................................................. 1 Arvidson, R. E. I Washington University ........................................................................................... 3 Baker, V. R. University of Arizona .............................................................................................. 7 I Balmino, G. Centre National d' Etudes Spatiales, Toulouse .................................................... 17 Banerdt, W. B. Jet Propulsion Laboratory .................................................................................... 19 I Basilevsky, A. T. Vernadsky Institute ............................................................................................... 21 Campbell, D. I Cornell University ................................................................................................ 25 Davies, M. The RAND Corporation ........................................................................................ 29 I Elachi, C. Jet Propulsion Laboratory ..................................................................................... 49 Goldstein, R. M. Jet Propulsion Laboratory ..................................................................................... 51 I Greeley, R. Arizona State University ....................................................................................... 53 Guest, J. E. I University of London Observatory ....................................................................... 59 Head, J. W., III Brown University .................................................................................................. 67 I Jenkins, J. SETI Institute ........................................................................................................ 91 Kaula, W. M. University of California, Los Angeles ................................................................. 95 I Keating, G. Langley Research Center ...................................................................................... 99 Kirk, R. L. I U. S. Geological Survey, Flagstaff ..................................................................... 103 Leberl, F. W. V excel Corporation ............................................................................................. 109 Malin, M. C. I Malin Institute ..................................................................................................... 119 McGill, G. E. University of Massachusetts ............................................................................... 123 I Moore, H. J. U.S. Geological Survey, Menlo Park ................................................................. 127 I I I MAGELLAN FINAL SCIENCE REPORTS I Table of Contents (Continued) I Muhleman, D. 0. California Institute of Technology ...................................................................... 131 Pettengill, G. H. I Massachusetts Institute of Technology ............................................................... 133 Phillips, R. J. Washington University ....................................................................................... 139 Sandwell, D. I Scripps Institute, University of California, San Diego ....................................... 145 Saunders, R. S. Jet Propulsion Laboratory ................................................................................... 149 I Schaber, G. G. U. S. Geological Survey, Flagstaff ..................................................................... 153 Schubert, G. I University of California, Los Angeles ................................................................ 163 Schultz, P. H. Brown University ................................................................................................ 171 Sharpton, V. L. I Lunar and Planetary Institute .............................................................................. 175 Sjogren, W. L. Jet Propulsion Laboratory ................................................................................... 179 I Soderblom, L. A. U. S. Geological Survey, Flagstaff ..................................................................... 183 Solomon, S. C. Carnegie Intitution of Washington ...................................................................... 189 I Squyres, S. W. Cornell University ............................................................................................... 199 Suppe, J. I Princeton University ........................................................................................... 201 Turcotte, D. L. Cornell University ............................................................................................... 205 I Tyler, G. L. Stanford University ............................................................................................. 209 Wood,J.A. Smithsonian Observatory .................................................................................... 213 I Zakharov, A. V. Russian Academy of Sciences, Moscow ............................................................. 219 I Acronymns ...................................................................................................................... 221 I I I I ii I I I Executive Summary I This volume is a brief summary of the scientific results of the Magellan Venus mapping mission as reported by the Magellan science investigators. I Magellan has exceeded all of its mission objectives by obtaining high resolution radar images, surface elevation, and radiometry for more than 98% of the planet. The amount of stereo data gathered on Venus is more than that available for any other planet. I Magellan's fourth cycle collected gravity data from an elliptical orbit to provide information on the relationships between surface features and the interior of the planet. I With the successful completion of the aero braking experiment, the spacecraft, in its lower orbit around Venus, has captured high resolution gravity near the poles from the nearly I circular orbit. Every attempt has been made to provide useful documentation for the complete Magellan data set. Magellan data have been released to the public through the Planetary Data System I (PDS) and the National Space Science Data Center (NSSDC) in photographs, lithos, brochures, digital form, and compact discs. With the release of Magellan data on the I compact disc read-only-memory (CD-ROM) a revolutionary new way of doing science has resulted. This technology provides a way to store, distribute and access large I volumes of data. The Magellan science investigators have utilized this wealth of data to provide I answers to questions we have been asking for a long time. I would like to personally thank everyone on the Magellan team for the success of this important mission, a mission I that has revealed information that will help us to better understand our own Planet Earth. R. Stephen Saunders I Magellan Project Scientist I I I I I I iii I INVESTIGATOR ROLE STATEMENTS I The following investigators were originally selected by NASA to participate in I the Venus Orbiting Imaging Radar (VOIR) Mission. When VOIR became an official NASA mission, the following role statements were established. The Radar Investigation I Group (RADIO) and the Gravity Investigation Group (GRA VIG) were reapproved when the Venus mapping mission that became the Magellan Project was established. These role statements include only the parts of each assignment that pertain to science analysis I and do not necessarily include Project Science Group (PSG) or PSG Working Group assignments. Each investigator selected was chosen for his expertise in carrying out I some of the responsibilities of the assigned investigation group. I Raymond Arvidson: His responsibility is to determine the nature and extent of the sedimentary cover on Venus and the extent of possible fluvial or eolian processes which I have contributed to the development and modification of this cover. He is also responsible for seeing that the data products are properly archived. As Chairman of the Data Products Working Group, he serves on the Project Science Group. I Victor Baker: His responsibility is to perform geomorphic analysis of the image I products of the Synthetic Aperture Radar (SAR) with emphasis on the interpretation of Venus landforms that are products of degradation, including analysis of features created I by eolian, fluvial, mass wasting, and weathering processes. I Georges Balmino: His responsibility is to produce the estimates of the spherical harmonic coefficients of the gravity field. I Nicole Borderies Rappaport: Her responsibility is to participate in the analysis and interpretation of the tracking data for gravity and geophysics