Re: Red dwarves, deep future

On 27 sept, 07:05, nos...@xxxxxxxxxx (Paul Ciszek) wrote:
In article <1189918753.573485.9...@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>,

<sigidu...@xxxxxxxxx> wrote:

This is a universe that's still reasonably hospitable to Life As We
Know It. Chemical-based life should still be possible. Red dwarves
aren't bright, but even a little star produces plenty of energy, so
there's plenty of power to support advanced civilizations doing
interesting things. The Red Dwarf Milky Way could still include
billions of worlds of sunlight -- okay, red sunlight -- breathable
air, and running water, supporting species or cultures that think in
time scales of billions or tens of billions of years. It could be the
long red afternoon of life in the universe.

The stars may last trillions of years, but the planets won't. An
Earthlike planet will eventually quit churning the techtonic plates
around, cease all vulcanism,

This part depends on the origin of internal heat.

Uranium and thorium become exhausted at a known timescale, and the
longer-lived isotopes like rhenium and rubidium do not have much
energy. But you might have significant tidal heating of interior...
any timescale for that?

and lose its air and water to space.

Why? When?

Mars has lost most air and perhaps some water. Venus has lost all
water and not much air. How much is Earth losing? Can a habitable
planet keep air and water for really long timescales?


.

Relevant Pages

  • Re: Use for hydrogen
    ... to deliver a fixed quantity of energy therefore it would deliver a lower ... in the middle of the Sahara and SW USA. Burn the hydrogen in air to ... Pour the water on to the sand. ... Grow trees on the now moist sand. ...
    (rec.arts.sf.science)
  • Re: [SLE] Warning to Americans!(now going OT)
    ... Splitting water into hydrogen and oxygen takes energy. ... The *only* reason that it's used in rocket engines is that it gives just about the best ISP possible for current technology in an engine that has enough thrust to get from sea level to orbit. ... An ICE burning H2 would have to use *twice* as much H2 as air, even if the air was pure oxygen -- with open air being largely N2, it's even worse. ...
    (SuSE)
  • Re: The instant solution to global warming, zero energy (no yeah right, hydrogen combustion)
    ... About 60% loss of applied energy doing this. ... electricity ... aside from electricity is water. ... waste product of air conditioners. ...
    (sci.astro)
  • Is the idea that hydrogen in the air can make energy a bb sensitive topic?
    ... Removing the need to transport energy. ... The concept to extract hydrogen requires electricity and two steps. ... Extract water from air. ... Extract hydrogen from the water through electrolysis. ...
    (sci.astro)
  • Re: How much enerygy required to evaporate one liter of H2O ?
    ... > the can than if you used that energy to run a vaccume pump. ... > than a burner on the stove could boil the water dry. ... and then dispose of the humid air. ...
    (sci.physics)