Rotational Period of the Planet Mercury

  title={Rotational Period of the Planet Mercury},
  author={G. Colombo},
  • G. Colombo
  • Published 6 November 1965
  • Physics, Geology
  • Nature
IN a recent communication by S. J. Peale and T. Gold1 the rotational period of Mercury, determined from radar Doppler-spread measurements to be 59 ± 5 days2, has been explained in terms of a solar tidal torque effect, taking into account the large eccentricity of Mercury's orbit, and the 1/r6 dependence of the tidal friction (r being the Sun–planet distance). They conclude from a very brief discussion that after slowing down from a higher direct angular velocity, the planet will have a final… 
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Rotation of the Planet Mercury
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A Radar Determination of the Rotation of the Planet Mercury
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Flux Density of the Radio Source CTA 102
OBSERVATIONS at 920 Mc/s by Sholomitsky1 suggest that the flux density of the radio source CTA 102 exhibits large variations with a period of about 100 days.