Spin state and moment of inertia of Venus

  title={Spin state and moment of inertia of Venus},
  author={Jean-Luc Margot and Donald B. Campbell and Jon D. Giorgini and Joseph S. Jao and Lawrence G. Snedeker and Frank D. Ghigo and Amber Bonsall},
Fundamental properties of the planet Venus, such as its internal mass distribution and variations in length of day, have remained unknown. We used Earth-based observations of radar speckles tied to the rotation of Venus obtained in 2006–2020 to measure its spin axis orientation, spin precession rate, moment of inertia, and length-of-day variations. Venus is tilted by 2.6392 ± 0.0008 degrees (1σ) with respect to its orbital plane. The spin axis precesses at a rate of 44.58 ± 3.3 arcseconds per… Expand

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