Posted on 01/21/2008 8:41:38 AM PST by Truth29
Oh yeah. The decision by Congress to redesign because it cost too much ran up the costs. Duh.
Then, involving the Russians probably doubled the cost of the station.
At present a MINIMUM of 20.25# of supplies, i.e., food, water, oxygen & fuel, is required per astronaut/day spent in space. 13 tons of supplies goes up, and 13 tons of waste comes down.
How big will the crew be? At present one would need to consider taking along at least crew_number *(20.25#/astronaut/day) * 450 (to 900) days.
Of course a water reclamation system would go far in reducing that amount somewhat. That means reclaiming water from feces, urine, sweat and breath.
It would also entail implementation of some system that recycles oxygen. Either break the C off of the CO2, and combine it with F4 (or something), or electrolyse the reclaimed water and pump the H into fuel cells. Dunno looks like some sort of sink to me. Certainly appears to have endothermic thermodynamic qualities (rather than exothermic thermodynamics).
Whatever transit vehicle/technology is implemented/utilized has to deal with the fact that solar radiation at Mars orbit is 2 1/2x what the astronauts experience in the ISS (although probably a little bit less on the surface - but not my much). Moreover, if a Venus swing-by gravity-assist is implemented in the orbital configuration (either outbound or inbound), radiation pressures are going to be a whole hell of a LOT higher than that.
Furthermore, transit will entail a goodly amount of interplanetary 0G time. Depending on the orbital configuration, a Venus fly-by gravity-assist may take as long as 400 days in its own right (either outbound or inbound - don't matter). The question is, will the crew be up to deal with that harsh 0.38G Mars surface environment after spending 200 days in interplanetary 0G?
I'm not going to even ask the quexion about what they're going to do after at least 200+ 0G days outbound, and 10-30 some odd 0.38G days ON Mars, and then some 200+ days on the return trip and the crew has to push some buttons during the 8+ G's re-entry phase.
OH! Oh! oh. ONE LAST THING: plants ain't growin' all so well in zero G. Nobody knows why, but they just ain't.
Quite frankly, I believe it to be a Fool's Endeavor.
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The crying shame here is that none of America’s hero MoonWalking Astronauts will be alive to witness their bretheren Astronauts walk on another Planet.
And they could have by now if only America hadn’t abandoned its focus on traveling to another Planet.
The other shame here is that those of us who saw them walk on Earth’s Moon on TV, won’t even be around to witness others walk on another Planet.
Alas, the “We Live In Two Different Worlds” Melody is going to have to be sung by somebody else.
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Moon Base Alpha was sabotaged if I recall...The explosion (theoretically impossible) launched the moon into deep space (kooky theory) but I really liked the show.
Additional reaction:LiveScience.com Blogs » Leonard David
Address:http://www.livescience.com/blogs/author/leonarddavid Changed:6:25 AM on Wednesday, January 23, 2008
Even worse, if we had continued on the track that Mercury, Gemini and Apollo had started, we would not only have lunar and Martian colonies, we would be on our way out to the asteroid belt and beyond.
It would also entail implementation of some system that recycles oxygen. Either break the C off of the CO2, and combine it with F4 (or something), or electrolyse the reclaimed water and pump the H into fuel cells. Dunno looks like some sort of sink to me. Certainly appears to have endothermic thermodynamic qualities (rather than exothermic thermodynamics).
It just so happens that I have been working on the electronic controls systems and the instrumentation of the ground test system for portions of the ECLSS (Environmental Control & Life Support System ) for the past 5 years or so.
This system takes sweat, urine, humidity, all of the excreted water and purifies it for re-use. The Columbia Disaster slowed down some of the work . We actually had some in-flight tests for the ECLSS system on Columbia. We got a great deal of the data before re-entry, but did not get everything.
We have GOT to get ECLSS on board the Space Station and operational. If we don't make ECLSS work, we don't go to Mars. It's that simple.
the point is that if they can have something with a design lifetime of 90 days operational after four years, how robust would an advance outpost with a five-year design lifetime be on Mars?No, the point is, the rovers don't have to come back, but humans do. Mars would be better and more thoroughly explored using robotic rovers controlled in realtime from Mars orbit. The astronauts would be in a shirtsleeves environment during their long trip to and from Mars, and while in orbit around it; the machinery will be exposed to space, and irrespective of semantics, that will be true of all human missions to Mars.
Work on tether systems means that the Mars crew may be able to spend the trip out and back in Mars-equivalent gravity, with the ship spun against a counterweight on a tether.
With my comment about the rover design lifetime vs. actual lifetime, I was responding to your comment about sending stuff ahead:
The problem with sending stuff on ahead is, all can be in perfect working order when the crew makes direct ascent, and fail when they’re a month away from Mars. They need to be sent with everything they’ll need for the trip. A decent level of redundancy will be a must.
They'll need to be sent with everything they need for a free return trajectory, not with everything they need for a months-long stay on Mars as von Braun and the old NASA reference mission proposed, because in the unlikely event that the advance-staged equipment fails while they're a month away from Mars, they'd just head on back.
I think we agree on the need to send them fully equipped, which is IMHO a good thing. The idea of “living off the land” on Mars won’t work until a much clearer idea is available about what the land actually can provide, and that will require a lot of reconnaissance on the surface, much more than Mars walks can provide. Once some idea of economically feasible exploitation of Martian resources is obtained, it’ll be time to determine whether or not a permanent human presence — of some kind — is feasible.
[my first-ever FR post, and some others]
http://www.freerepublic.com/focus/f-news/1051021/posts?page=8#8
http://www.freerepublic.com/focus/f-news/1088571/posts?page=46#46
http://www.freerepublic.com/focus/news/1513003/posts?page=12#12
Bono plan, something probably of interest:
http://www.freerepublic.com/focus/f-news/1593602/posts?page=16#16
Gilbert Lewin:
http://mars.spherix.com/
The water can be split for more hydrogen, and a supply of oxygen. The mass leverage here is 18:1, since you only have to bring the lightweight hydrogen, and pull the heavy carbon and oxygen out of Mars resources.
Testing has already been done in this regard:
It's pretty simple chemistry.
As a test, on Mars, using robotic systems, it might make some sense to try it. But fuel is a very small component of the cost of spaceflight — it’s mostly the cost of the technology. And making fuel for a return trip doesn’t make Mars economical to colonize.
Is the ECLSS scheduled for transportation to the ISS by the shuttle during any of its remaining missions? Or will the equipment fit on the Russian Soyuz or Progress vehicles? Thanks.
Last I heard, it was scheduled for the middle of 08 on a shuttle. IT is definetely planned to go up on one of the remaining shuttle flights.
Indeed, the ISRU testbed folks are probably working toward a flight-worthy system for a test on Mars.
The “cost” or “economy” of making fuel on Mars isn’t the issue, it’s the mass - if you have to drag 1/18th the mass in fuel from Earth to Mars, that’s a mass budget that can be used for more science equipment or amenities for the crew.
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