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But it has a 90 bar atmosphere!  And even so, most of the lighter elements have been lost (hydrogen, helium, nitrogen, oxygen).  Now only CO2 is left. 

Why didn't the ionosphere stop the lighter gas molecules being lost?

I stand corrected.  The chance is merely vanishingly small.

So I believe the ionosphere can provide the surface with radiation shielding even in the absence of a magnetic field, but I don't believe that the ionosphere can prevent itself being blown away by the solar wind in this situation.

Is Celestia ED something different from Celestia?  If not, then I don't believe that it models atmospheric evolution.

I believe the Moon had at atmosphere that was constantly replenished by volcanic activity for billions of years, but once the volcanic activity stopped, the atmosphere blew away in the solar wind (there are still traces left).

But Mars is a counterexample to your theory.  It did have a thick atmosphere and its ionosphere did not protect it.

The ionosphere isn't something magic.  It is just gas atoms with electrons stripped away.  Without the magnetic field, they just blow away like normal gas atoms.  With the magnetic field, they are directed along the field lines and kept close to the planet. 

It is the magnetic field that is important.  If you have an atmosphere with a magnetic field, the solar wind will soon create an ionosphere.  But not vice versa.

Do you have any evidence for this statement?  I'm quite interested in this area, so if you've seen any calculations, I'd appreciate a reference to them.

Again, what makes you think this is true?

How does an "inactive central core" prevent the maintenance of a "liveable atmosphere" ?

But Earth is deep within a gravity well, and the vacuum and viewing conditions are better at L5.  A terraformed moon would make a great base for exploiting the rest of the solar system.

I'm sure a balance can be struck.

Unconsidered destruction is foolish, however the human population has grown so large that we can no longer live without environment modification.

Or ... build a linear accelerator on Phobos, compact the carbon into bullet shapes and then shoot them at the ice deposits. 

Carbon + ice + heat from impact -> CO2 + methane + water vapor

I thought you might be able to burn Phobos carbon like coal for energy, but it would take more energy to split out the oxygen from the water than you'd get from burning the carbon.  You could use it to lower the energy cost of CO2 production though.

What an interesting idea, nickname.  We need a better characterization of the crust of Phobos to plan in more detail.

Hi Alien baby, welcome to New Mars.

I vote for the WiFi idea - or whatever packet-switched high-bandwidth self-organizing wireless data network is in vogue at the time.

Communication towers will be easier to build on Mars because of the lower gravity.  You can also use tethered balloons as ad hoc communication towers (during exploration).

Surprising it got funded really 

I quite like this idea.  It'd be hard - the incoming iceteroid would be moving very fast - you'd have to adjust it's velocity so that it would arrive at the right phase of the moon's orbit and, of course, the target is a lot smaller - but I think it is possible if you design for it.

You'd still get quite a large kaboom at the moon, preferably Phobos, so you'd get some moon dust coming down to Mars as well - but you wouldn't even notice if it came down during a dust storm - and, like you say it's all nice carbon/organic matter.

A 10 billion ton iceteroid (2.3 km diameter) is about 1/1000th the mass of Phobos - still it'd have quite a bit of momentum and would modify Phobos' orbit, particularly if you hit it repeatedly.  Perhaps we could kill two birds with one stone here (as it were) and modify Phobos' orbit so that it isn't in the way of a space elevator.

Not a bad thought, although Phobos with lots of water isn't a bad asteroid mining base by itself (assuming humans can live happily in low g).

Actually the 45% figure is for the top of the atmosphere.  On an annual basis, the Martian surface receives ~450 W/m^2 vs. an average of ~200 W/m^2 for the Earth's surface because the Martian atmosphere is thinner.  The middle of the Sahara, on a perfectly clear day, can peak at ~1000 W/m^2, but most of the Earth's surface doesn't receive that.  During seasonal dust storms on Mars, light received at the surface can drop to ~100 W/m^2 (about the annual average for Seattle).

The 300 year figure is just for thermal escape, it doesn't even take into account stripping by the solar wind

-70 Celsius doesn't meet the usual criteria of terraforming, and I'm sure you can appreciate how quickly billions of years would become hundreds since thermal escape is governed by a power law.

I think you're being a little optimistic here, but I hope we both get to walk in lunar forests one day