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Kamoun, P. G.

Publications and source records attributed to Kamoun, P. G..

2 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1982

Comet Encke - Radar detection of nucleus

The nucleus of the periodic comet Encke was detected in November 1980 with the Arecibo Observatory's radar system (wavelength, 12.6 cm). The echoes in the one sense of circular polarization received imply a radar cross section of 1.1 + or - 0.7 sq km. The estimated bandwidth of these echoes combined with an estimate of the rotation vector of Encke yields a radius for the nucleus of 1.5 +2.3 or -1.0. The uncertainties given are dependent primarily on the range of models considered for the comet and for the manner in which its nucleus backscatters radio waves. Should this range prove inadequate, the true value of the radius of the nucleus might lie outside the limits given.

Kamoun, P. G.↗
NASA NTRS1982

Radar detectability of comets

Earth-based radar observations of comets are restricted to the detection of the nucleus since detection of an echo from the dust or from the plasma near a comet seems infeasible. The successful detection of the nucleus can provide information on its size, spin vector, surface-scattering properties, and orbit. Only P/Encke has so far been detected by radar, and that detection was marginal. At most, three other known comets could be detected by radar within the next five years.

Kamoun, P. G.↗