Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Science 20 June 1975:
Vol. 188. no. 4194, pp. 1211 - 1212
DOI: 10.1126/science.188.4194.1211
Prev | Table of Contents | Next

Articles

Ganymede: Observations by Radar

R. M. Goldstein 1 and G. A. Morris 1

1 Jet Propulsion Laboratory, California Institute of Technology. Pasadena 91103

Radar cross-section measurements indicate that Ganymede scatters to Earth 12 percent of the power expected from a conducting sphere of the same size and distance. This compares with 8 percent for Mars, 12 percent for Venus, 6 percent for Mercury, and about 8 percent for the asteroid Toro. Furthermore, Ganymede is considerably rougher (to the scale of the wavelength used, 12.6 centimeters) than Mars, Venus, or Mercury. Roughness is made evident in this experiment by the presence of echoes away from the center of the disk. A perfectly smooth target would reflect only a glint from the center, whereas a very rough target would reflect power from over the entire disk.


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Radar Glory from Buried Craters on Icy Moons.
V. R. Eshleman and V. R. ESHLEMAN (1986)
Science 234, 587-590
   Abstract »    PDF »
Galilean Satellites of Jupiter: 12.6-Centimeter Radar Observations.
D. B. Campbell, D. B. CAMPBELL, J. F. CHANDLER, G. H. PETTENGILL, and I. I. SHAPIRO (1977)
Science 196, 650-653
   Abstract »    PDF »
Restored Pictures of Ganymede, Moon of Jupiter.
B. R. Frieden, B. R. Frieden, and W. Swindell (1976)
Science 191, 1237-1241
   Abstract »    PDF »


To Advertise     Find Products

Science. ISSN 0036-8075 (print), 1095-9203 (online)