Valéry Lainey

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[1] Any model of tides is based on a specific hypothesis of how lagging depends on the tidal-flexure frequency c. For example, Gerstenkorn (1955), MacDonald (1964), and Kaula (1964) assumed constancy of the geometric lag angle d, while Singer (1968) and Mignard (1979, 1980) asserted constancy of the time lag Dt. Thus each of these two models was based on a(More)
Io is the volcanically most active body in the Solar System and has a large surface heat flux. The geological activity is thought to be the result of tides raised by Jupiter, but it is not known whether the current tidal heat production is sufficiently high to generate the observed surface heat flow. Io's tidal heat comes from the orbital energy of the(More)
Any model of tides is based on a specific hypothesis of how lagging depends on the tidalflexure frequency χ. For example, Gerstenkorn (1955), MacDonald (1964), and Kaula (1964) assumed constancy of the geometric lag angle δ , while Singer (1968) and Mignard (1979, 1980) asserted constancy of the time lag ∆t . Thus, each of these two models was based on a(More)
We present a new theory of the four Galilean satellites Io, Europa, Ganymede and Callisto. This theory aims to deliver highly accurate ephemerides able to represent the Galilean satellites’ motion over several centuries. It is based on the numerical integration of elaborated equations of motion. This first paper describes and tests many usually neglected(More)
Different theories of bodily tides assume different forms of dependence of the angular lag 8 upon the tidal frequency %. In the old theory (Gerstenkorn 1955, MacDonald 1964, Kaula 1964) the geometric lag angle is assumed constant (i.e., 8 ~ x), while the new theory (Singer 1968; Mignard 1979, 1980) postulates constancy of the time lag At (which is(More)
Like our Moon, the majority of the solar system's satellites are locked in a 1:1 spin-orbit resonance; on average, these satellites show the same face toward the planet at a constant rotation rate equal to the satellite's orbital rate. In addition to the uniform rotational motion, physical librations (oscillations about an equilibrium) also occur. The(More)
GAIA will provide observations of some multiple asteroid and dwarf systems. These observations are a way to determine and improve the quantification of dynamical parameters, such as the masses and the gravity fields, in these multiple systems. Here we investigate this problem in the cases of Pluto’s and Eugenia’s system. We simulate observations reproducing(More)
  • Vincent Robert-Pélissier, Jean-Pierre De Cuyper, +14 authors N. Zacharias
  • 2017
The astrometric monitoring of the natural planetary satellites is an important step to assess the formation and the evolution of these systems. However, in order to quantify relevant gravitational effects such as tidal forces, it is necessary to have very accurate observations over a long time interval. Unfortunately, the accuracy is decreasing as one(More)
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