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Richard Hoagland claims finding all this water/ice on Mars will greatly reduce the cost of a round trip manned mission. We can now break down the water over there and refuel.
How much of a savings will that bring?
Will this discovery of water speed up a manned mission? I don't feel like waiting another 20 years!
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I'm hoping this discovery of water on Mars doesn't go ignored by the popular press. If the press gives the water discovery a two sentence blurb or a three line article on page 18, I don't think we can count on public interest as a force that will drive us to Mars quicker. I haven't seen the discovery really trumped up as big news yet, and it's sad when the BBC seems more interested in reporting on it then the press in NASA's own country. Of course if the people who have the power to get the ball rolling can do it anyway, screw what the public and the press thinks.
To achieve the impossible you must attempt the absurd
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Apparently H2/O2 rocket fuel, which we now know we can at least theoretically manufacture from Martian water (Let's hear it for oceans of lovely Martian water!!!.... ), is a very good rocket fuel. It has an Isp (Specific Impulse) of 450 seconds, which I understand is close to the best you can get out of chemical fuels.
The fuel put forward by Bob Zubrin for the first ERVs is CH4/O2, or methane/oxygen, which has an Isp of only 380 seconds.
The snag with the hydrogen/oxygen fuel is the fact that it's hard to store for any length of time.
For the time being, then, it may be as well to stick with methane/oxygen which is easier to deal with and yet still gives very adequate performance. Besides, a fully automated, prototype, in-situ-propellant factory has already been tested and shown to work satisfactorily.
Certainly for the future, though, Martian water is going to be an absolute boon for fuel production and so many other things! Not least of which might be a great big beautiful ocean in the northern hemisphere!!!
Maybe this will be the turning point!
The word 'aerobics' came about when the gym instructors got together and said: If we're going to charge $10 an hour, we can't call it Jumping Up and Down. - Rita Rudner
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It seems to me that if you bring a small nuclear reactor and have access to as much water - H2O - and carbon dioxide - CO2 - as you can use, making H2/02 fuel -or- making methane CH4/O2 fuel is fairly simple.
Run the MarsDirect sabatier process, except you do NOT need to bring H2 feedstock from Earth. No cryogenic H2 tanks being lofted into LEO and no fancy technology to prevent the H2 feedstock from sublimating (boiling off) during the CRV's trip to Mars.
Not needing to bring cryogenic H2 from Earth would seem a major cost savings all by itself.
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I agree completely that a proven source of hydrogen on Mars will eliminate all the problems involved in bringing it from Earth.
However, in the initial stages with the Mars Direct plan, we need to create a fuel supply we can leave sitting in its tanks on the surface until required for Earth return. That's all I meant ... I was just advocating sticking with the CH4/O2 system rather than H2/O2 for that reason.
But the prospects for the future when we have a permanent colony are infinitely brighter now, as you so rightly point out Bill!
I get goosebumps just thinking about it!
The word 'aerobics' came about when the gym instructors got together and said: If we're going to charge $10 an hour, we can't call it Jumping Up and Down. - Rita Rudner
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