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Comet encke: radar detection of nucleus
Science (New York, N.Y.)
|April 16, 1982
Summary
Radar observations detected Comet Encke
Area of Science:
- Planetary Science
- Cometary Nucleus Research
- Radio Astronomy
Background:
- Periodic comet Encke is a subject of interest for understanding cometary nuclei.
- Previous studies have relied on indirect methods to estimate nucleus size.
Purpose of the Study:
- To determine the size of Comet Encke's nucleus using radar observations.
- To refine estimates of cometary nucleus dimensions.
Main Methods:
- Utilized the Arecibo Observatory's radar system operating at a 12.6-centimeter wavelength.
- Analyzed radar echoes in a specific circular polarization to infer nucleus properties.
Main Results:
- Detected the nucleus of Comet Encke.
- Measured a radar cross section of 1.1 +/- 0.7 square kilometers.
- Estimated the nucleus radius to be 1.5(+2.3)(-1.0) kilometers, with uncertainties dependent on scattering models.
Conclusions:
- Provided a radar-derived estimate for the radius of Comet Encke's nucleus.
- Highlighted the impact of scattering models and nucleus rotation on radius estimation.
- Acknowledged potential for the true radius to fall outside the calculated range due to model limitations.
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