The moon and the planets

, Volume 24, Issue 1, pp 13–45 | Cite as

The history of titan, of Saturn's rings and magnetic field, and the nature of short-period comets

  • E. M. Drobyshevski
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Abstract

Titan in the past, just as Ganymede, had a massive ice envelope subjected to volumetric electrolysis under the action of unipolar electric current generated through the interaction of the satellite with Saturn's magnetosphere.

The electrolysis products concentration required to cause explosion could become accumulated only under conditions of an exponential decay of Saturn's magnetic field in time (with τ ≈ 0.55 Gyr) which implies a relict nature of the field and agrees with the present ideas on the planet's structure.

The explosion of the electrolysis products contained in the ice envelope resulted in Titan's having lost ∼13% of its mass in the form of gas (mainly of water vapor) and solid ice fragments, as well as in the appearance on Titan of an atmosphere (of volatile products from incomplete combustion of hydrogen and hydrocarbons) and a deep (∼1000 km) ocean of liquid water. The presence of liquid water on Titan's surface is confirmed by an analysis of the available microwave measurements of brightness temperature.

The condensation of the water vapor lost by Titan produced the visible inner rings of Saturn while large solid fragments of the ice envelope govern their dynamics. These are also located in the gap between Rhea and Titan (the G ring?). Most of the ice fragments were swept out from Saturn's system through perturbations by Titan. They made up a reservoir of cometary nuclei beyond Jupiter's orbit.

Arguments are presented in favor of a recent (3–10 thousand years ago) explosion of Titan. Some implications from these concepts, lending themselves to observational testing, are pointed out.

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Copyright information

© D. Reidel Publishing Co. 1981

Authors and Affiliations

  • E. M. Drobyshevski
    • 1
  1. 1.A.F. Ioffe Physical-Technical InstituteU.S.S.R. Academy of SciencesLeningradU.S.S.R.

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