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Venus: radar determination of gravity potential
Science (New York, N.Y.)
|February 2, 1973
Summary
Scientists determined Venus' gravity potential using multi-frequency radar. This method maps surface height and pressure, revealing gravity contours and potential links to topography.
Area of Science:
- Planetary Science
- Radio Astronomy
- Geophysics
Background:
- Venus' dense atmosphere significantly absorbs radio waves, complicating surface measurements.
- Understanding Venus' gravity field is crucial for deciphering its internal structure and evolution.
Purpose of the Study:
- To develop and apply a novel method for mapping Venus' gravity potential.
- To investigate the relationship between gravity anomalies and surface topography on Venus.
Main Methods:
- Utilizing multi-frequency radar measurements to account for atmospheric absorption.
- Comparing radar reflection intensities at different frequencies to determine surface height relative to pressure contours.
- Combining height data with echo delay measurements to map pressure and gravity potential contours.
Main Results:
- A gravity equipotential contour for Venus' equatorial region was generated.
- A tentative upper bound of 6 x 10(-4) was established for the fractional difference in Venus' principal equatorial moments of inertia.
- Minima in the gravity equipotential contours were observed to correlate with topographic minima.
Conclusions:
- The developed radar method effectively determines Venus' gravity potential.
- Gravity minima are likely associated with Venus' topographic features, suggesting a link between internal mass distribution and surface morphology.
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