It proposes that Enceladus has a highly porous core, allowing water from the ocean to easily permeate it, where tidal friction
causes it to heat up.
Our galaxy could be full of isolated ecosystems inside icy moons and planets, many of which are kept liquid by radioactive isotopes, and tidal friction
driven by nothing more than orbits and spins--truly the children of celestial mechanics.
There is a fundamental difficulty, well-known among specialists in the field for many years, in extrapolating the 38 mm/year current rate of lunar recession back in time, by the equations of tidal friction
, to the early days of the Earth-Moon system--running the film backwards would have the Moon crash into the Earth only 1 .
Close-in planets seem to orbit their stars faster than the stars themselves rotate, so this tidal friction
will have the opposite effect.
Further complicating simple resonance calculations is tidal friction
, which is believed to subtract considerable energy from the system (Greenberg et al.
In fact, even today, considerable heating due to tidal friction
would be expected by this constantly moving barycenter, giving rise to convection currents and in effect resolving the enigma of its application to the subduction phenomena that causes seafloor spreading and which pushes one continent under another.
The Earth is spinning, and because of the tidal friction
of the moon on the Earth, it slows the spin down, so then the moon has to move away to compensate for that.
A possible solution to the dilemma arises from a process known as Kozai Cycles with Tidal Friction
Scientists know the Earth's spin has slowed through time because of tidal friction
- energy lost as the moon causes water to slosh around the globe.
If the first planet were alone, tidal friction
would have made its orbit round.
A likely explanation is that another, unseen massive planet a little farther out from the star is in a gravitational resonance with HAT-P-2b and, like a kid pumping a swing, is pumping it into an elliptical orbit as fast as tidal friction
can dissipate the added energy away.
and heating may have inflated the planet's atmosphere, causing much of it to escape and leaving behind a core that might be primarily iron and rock (S&T: May issue, page 26).