Astronomy and Astrophysics – Astronomy
Scientific paper
Jan 2011
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2011aas...21722105b&link_type=abstract
American Astronomical Society, AAS Meeting #217, #221.05; Bulletin of the American Astronomical Society, Vol. 43, 2011
Astronomy and Astrophysics
Astronomy
Scientific paper
Terrestrial planets in the classic "habitable zone" (Kasting et al. 1993) of stars may be influenced by tides. Tidal evolution is poorly constrained and multiple acceptable models exist which, although qualitatively similar, predict different rates of evolution. Using different models, we examine how tides may modify several key properties of planets in the habitable zone: semi-major axis, eccentricity, obliquity and rotation rate. Tides can lock the rotation rate and erode the obliquity (to 0 or 180 degrees) in 103-1010 years, depending on the stellar mass and eccentricity. Some tidal models even predict significant obliquity evolution for planets in the habitable zones of solar-mass stars. This evolution dissipates energy in the planet's interior (at the expense of the orbit) and leads to "tidal heating." In extreme cases of high eccentricity and very low mass stars, the heating may initiate a runaway greenhouse, and/or total evaporation of potential surface water, eliminating any hope of habitability. After the spin properties have equilibrated, the planet is said to be "tidally locked" and further evolution primarily changes the orbital angular momentum. For exoplanets, tides tend to reduce eccentricities and semi-major axes, and can also change the rotation period, eventually reaching synchroneity with the orbit when both eccentricity and obliquity reach zero. Orbital circularization requires millions to trillions of years, depending on the planet's initial conditions and the tidal model assumed. Tidal heating also occurs during circularization and planets may pass through a "super-Io" phase prior to reaching internal heating rates similar to the modern day Earth. Tides clearly have the potential to impact habitability and may lead to planets with evolutionary paths markedly different from the Earth. These issues are presented and discussed for the simple case of one planet orbiting one star.
Barnes Rory
Greenberg Richard
Heller Rainer
Jackson Bailey
Leconte Jérémy
No associations
LandOfFree
The Role of Tides in Planetary Habitability does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The Role of Tides in Planetary Habitability, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Role of Tides in Planetary Habitability will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1397724