As it is, the presented concept follows more of a Mars Direct style plan, where the propellant is produced on Mars prior to the actual lift-off from Earth.
Yeah, but this was supposed to be something we could do now, without any significant development. Mars ISRU fails that criterion.
Quote from: 93143 on 10/29/2010 07:18 pmYeah, but this was supposed to be something we could do now, without any significant development. Mars ISRU fails that criterion.I actually agree, but Mars Direct is also supposed to be something that can be done "now".
Quote from: Warren Platts on 10/29/2010 07:23 pmQuote from: 93143 on 10/29/2010 07:18 pmYeah, but this was supposed to be something we could do now, without any significant development. Mars ISRU fails that criterion.I actually agree, but Mars Direct is also supposed to be something that can be done "now".Martian ISRU is rather easy, actually, since you can grab the oxygen (and fuel, actually) right from the air anywhere on the planet. This technique has been demonstrated, but not on the surface of Mars.
Quote from: Robotbeat on 10/29/2010 07:25 pmQuote from: Warren Platts on 10/29/2010 07:23 pmQuote from: 93143 on 10/29/2010 07:18 pmYeah, but this was supposed to be something we could do now, without any significant development. Mars ISRU fails that criterion.I actually agree, but Mars Direct is also supposed to be something that can be done "now".Martian ISRU is rather easy, actually, since you can grab the oxygen (and fuel, actually) right from the air anywhere on the planet. This technique has been demonstrated, but not on the surface of Mars.TRL < 5 . Period.Which, to me means only one thing : stop campaigning for manned martian sorties. Start campaigning for ISRU tech shakeout missions.
What do you mean by "demonstrated"? A lab tabletop demonstration on Earth's atmosphere doesn't prove much more than the theoretical enthalpy of formation of CO2...
Quote from: Warren Platts on 10/29/2010 08:52 pmWhat do you mean by "demonstrated"? A lab tabletop demonstration on Earth's atmosphere doesn't prove much more than the theoretical enthalpy of formation of CO2...The very definition of TRL 4
All the speculation doesn't change the fact that _any_ ISRU hasnt ever gone beyond TRL4.Which effectively kills the concept.And if anyone wants to help the cause along, the most productive way would be to put together a cheap, reasonably priced proposal ( say, less than $200M lander ) that would actually fly an ISRU demo, and optionally light a rocket on Mars using the produced propellant.
Actually having a budget would help as well. It is time some of the RATS hardware flew.
[quote author=guru link=topic=23169.msg653268#msg653268 There have been no demos of ISRU ever, in the history of spaceflight.The TRL of martian propellant production is what, 3 or 4?That kills your proposal right there.Before ISRU propellant production is demoed on an unmanned mission, its just not a sane approach.
I don't like putting technology development programs on the critical path to a mission, but atmospheric ISRU, in spite of it low TRL, is still comparatively simple and will be required for any sane Mars mission anyway.
Also, why sniff for methane when there is water in the soil practically everywhere that could be converted to high Isp LH2/LO2?