We will need a faster propulsion system than what we have now. Something like Project Orion, where the transit time is days rather than months. That IMO is the sine qua non of a manned mission.
I have heard that option as well, but some ‘experts’ I have spoken on phone/chatted online with over last few years have said that would reuire more supplies/weight/time/shielding of capsule for longer exposure to radiation effects, scaling up the overall cost(s). Its a trade-off of different options - at best is a judgement call for the most part. I am sure it’ll be a trade-off of various options based on safety issues prior to mission leaving Earth.
I say clearly I have just an informed opinion, not at being an ‘expert’ by any means. One of the couple of NASA-employed (or retired from) guys I spoke with many times only a few years ago was a high-level Astronaut Safety Trainer/Officer for some Apollo/STS operations, so his/their words carry some weight, obviously. Gave me a lot of learning/understanding of the dynamics of long-term space-travel issues. This was a couple years ago, though, so advances have surely been made in a number of areas.
I even ran, on my computer, a number Excel-based escape-rocket performance calculations one guy came up with that he presented publicly and to his old workmates (and personally meeting with NASA’s Director, I hear) with the data that helped ‘doom’ the cancelled Ares program since his laptop was not powerful enough to give the results in a timely manner. If the Ares had to abort in-flight due to an explosive incident, the human-contain capsule would, more than likely than not, be engulfed in the fireball/flaming pieces of solid-booster contents from the lower stage(s), per the calc’s he showed. A serious issue of safety for human-rated spaceflight requirements, so to speak.
BUT, just this morning, a privately-owned large rocket for a resupply-capsule mission to ISS managed to ‘land’/target-accurately its first stage upon a relatively-small floating barge way downrange, but it was not a ‘purely successful landing’ as the first-stage was destroyed by excessive downward velocity, IIUC, from nasaspaceflight.com’s forum - it’ll get worked out, no doubt. Close enough to have me cheering out loud as I ‘monitored’ the event live online. YEAH for SpaceX’s ambitions! Being able to launch more stuff, much cheaper, makes putting essential things on Mars in advance of human presence is, no doubt, a BIG advantage, but its very costly right now to do multiple launches for one mission. Economics of ‘getting there’ play a big role (or the major role, IMHO). At least that is what I was ‘schooled’ at on this subject at that time. Advances will be made, and we will get there eventually. 
There seem to be probes leaving for Mars every month these days. (Why don’t they send a lander to Mercury instead?) Although it’s slow going, those landers are almost certainly a more cost effective way to gather the same data. But you don’t go do something that’s borderline impossible just to gather data. You do it because it’s there. Also, in the long term we need to move off this planet.
Apart from cost my main problem with sending people to Mars is that we’ll then have polluted another planet with our microbes.
But suppose we want to do it. Yes, sending supplies and return vehicles in advance would be an important part of making it work. I really should learn how to do the numbers, but is there really no way to do all of this faster than in two years? If we can make fuel on the moon it shouldn’t be too much of a problem to bring the fuel needed for a much faster trajectory.
Also, what about accelerating the interplanetary ships in advance with gravity assists, and then use the smallest possible shuttle to accelerate the astronauts and catch up with the interplanetary ship?
What about energy? How much would you need to keep a bunch of astronauts alive for months? And would it make sense to use an ion motor, or would the enormous solar panels required to get worthwhile acceleration be a non-starter? I suppose all of this will work a lot better once we have working fusion. Or maybe use a fission nuclear reactor for energy?
What would be the best crew size? Six seems like a good number, that’s enough to get some variety in the personal interactions. Or maybe make it just two, then there’s only one relationship to worry about.
Sending crew is certainly risk, and inarguably more expensive by a couple of orders of magnitude than even a complex robotic mission like the Mars Science Laboratory. But I think we need to bear in mind that a good portion of the cost is due to our current very primitive chemical propulsion and habitat systems, and also because we have to lift every required environmental supply and propellants from the surface of the Earth at great expense (>$20k per kilogram for superheavy lift vehicles). In consideration of the “pointless”-ness, we need to evaluate what legitimate goals may exist in terms of exploration.
Certainly, in just collecting scientific information about Mars or any other body, robotic systems can do much of the same work at a much lower marginal cost, and when supported by an Earth-based “crew” can be directed to perform most of the same capabilities as a human astronaut without constantly having to manage workload, ameliorate fatigue and stress, and ultimately having to return to Earth. However, robotic systems do not currently have the (or expected in the near term) capability to make onsite evaluations of conditions, and because of the time delay in communications this limits the responsiveness of such a system. There is also the relatively inflexibility of a robotic system; although such systems have been developed to much greater capability since the early Mars rovers, a human astronaut in a “shirtsleeve” environment is still more mobile and articulate, although having to work in pressure suits as currently designed are quite restrictive both in terms of manipulation and perception. (Working in a pressure suit can be approximated by wearing heavy scuba gear with extra gloves, a motorcycle helmet, and a weight vest.)
A crewed mission to Mars of six astronauts would require a landing vehicle of >40 T landed mass (more likely 60 T) even with a pre-staged environment and resources and would only be able to explore about a 50 km radius at best. A long duration (conjunction class) mission would require nuclear power on surface as well as sufficient resources to survive an almost year and a half duration. None of these are insoluble problems with sufficient time and budget, but the costs are extraordinary; the best estimates on a conjunction-class mission are consistently in the US$500B range without consideration for unique challenges which may be encountered in technology development, and still represent a minimum maturity model; in other words, technology is developed only to the minimal capability to achieve the mission objectives with no additional planned effort to mature the technology. This is the same type of program as the Apollo moon landing program, what we call a “destination-oriented” program. The problem with such programs is that once they achieve their initial objectives public and political support evaporates.
The other real problem with a Mars (or other interplanetary) mission using extensions of extant propulsion and habitat technology is that with the limited capability for robustness and amount of crew, any sort of major problem or disaster would either be totally unrecoverable, resulting in a total loss of mission, or would consume resources and prevent critical exploratory and scientific objectives from being achieved. The Apollo 13 mission is often hailed at being such a “successful failure” in recovering from a critical flight failure in the propulsion system, but in fact it was just plain a failure, achieving no mission objectives and only recovering the crew because it occurred on the outbound leg after CSM-LM docking, and because of the extensive planning in using the LM as a lifeboat. (Unlike the entertaining but factually inaccurate Ron Howard film, the procedures were not nearly as ad hoc as presented and were largely already developed for this kind of contingency.) A similar category of failure on a crewed Mars mission on either the outbound or return leg would represent loss of mission (and very likely loss of crew) at a cost of many hundreds of billions of dollars. For the same cost, the surface of Mars could literally be peppered with rovers, and the loss of a handful would be a comparatively inconsequential loss in overall objectives. Even what we currently consider minor nuisances such as the abrasive silicate-rich dust of Mars may present significant health and operational concerns for a human crew that would limit the ability of the crew to operate effectively.
That being said, this is all in consideration of the extrapolation of existing technologies and capabilities. Developing the capability for in situ resource utilization of space-based resources, propulsion technology, space habitation technologies, et cetera in a near Earth capacity would reduce the threshold cost of any interplanetary mission to the point that the expense of a crewed mission may be more comparable in terms of cost per capability to purely robotic missions, and would represent a rational focus for development of space technologies. In addition, combining robotic and crewed exploration would allow the best of both capabilities; a local “crew” operating robotic probes and rovers of various capabilities from orbit may well present the best value for operating dollar, especially in operating in unmitigatedly hazardous environments such as the Galilean moons of Jupiter.
The notion of human settlers migrating en masse to Mars growing crops in greenhouses under the pale Martian sky, or miners with laser pickaxes prospecting asteroids is about as realistic a plan for human exploration and exploitation of space resources as the writings of Jules Verne. But this doesn’t mean that humans don’t have a place in space; by the contrary, developing the necessary technologies to explore and use space resources will enable relatively inexpensive and low(er) risk human exploration and habitation, leaving only the problem of getting from Earth surface to orbit more cheaply than current chemical propulsion methods. We won’t solve this by going to any particular destination; it requires a focused effort to develop and mature enabling space technologies to allow for a wide array of utilization and habitation capabilities.
Stranger
If the astronauts don’t land and use the commonly cited 6/12/6 month mission plan, they’d have to be in microgravity for two years, which could be a death sentence in its own right.
Considering how tricky launching stuff from the earth’s surface into space is, it seems rather insane to launch a rocket, land it on another planet and then have it lift a bunch of astronauts into space. But hey, it worked for the lunar missions. Landing big and heavy stuff and breakable humans on Mars may actually be harder than lifting off, as for the latter the atmosphere is much less relevant.
Anyone agree that trying to build most of this on the moon rather than launch from earth would make more sense?
IF you actually had the infrastructure in high orbit to build spacecraft and their equipment in situ, ala’ O’Neil’s The High Frontier. Otherwise you’re simply using the moon as a staging area while still having to initially boost everything off Earth.
Even that could help. But presumably, at least a few things could be manufactured from local materials. At the very least you could get oxygen from the silicate rocks.
I don’t see how. You lift everything from Earth’s gravity well, land it on the Moon and then lift out of the Moon’s gravity well. It seems like a waste of fuel.
3 married couples would probably be best for overcoming boredom.
Yes, if you have to bring everything to the moon first, then you waste fuel. However, construction will be much easier in the presence of gravity and it would be relatively easy to create large working spaces where your materials stay put and with a breathable atmosphere (something like 0.25 atmosphere pressure pure oxygen).
The moon is of course full of oxygen and various metals, so if manufacturing on the moon is possible then you could save a lot on bulk material transport from earth. If water can be found that’s even better, because then you can manufacture fuel on the moon.
The issue of human sexuality (and the superset of psychological and sociological issues in general) is a significant one. Although the possibility of selecting married couples for interplanetary missions has been suggested, there are strong arguments against, specifically that married couples may either work more with each other, or alternatively against one another (depending on the dynamics of the relationship), resulting in problems with the social cohesiveness and ultimately performance of the crew. Of course, the same could occur with unmarried but romantically bonded couples (of either mixed or same gender, so just selecting an all-male or all-female crew doesn’t necessarily resolve such issues). The long transit duration (8 to 9 months for a Hohmann transfer rather than the 6 months cited earlier) and the long surface stay for a conjunction-class mission argues against too small of a crew. Although NASA has previously argued for its rigorous screening process as eliminating candidates with potential mental or emotional issues, the recent public issue with Lisa Nowak (in a romantic rivalry with another astronaut over a third), issues with the emotional health of astronauts on the ISS, and disclosures about various emotional and substance abuse problems from well-regarded astronauts like Buzz Aldrin argues that screening alone isn’t enough; the inherent stress of the highly selective astronaut selection process and the isolation of years spent in the confines of a small habitat require actively managing the emotional state and social relationships of a crew on an interplanetary mission. And it isn’t as if some kind of flight psychologist at Mission Control is going to be able to influence the situation; it will have to be a set of skills which are currently barely even discussed in astronaut training and conditioning.
Stranger
For about a month; after that the novelty wears off, and if you think it’s hard for two people to make a relationship work, try six.
Didn’t Aldrin begin drinking to excess after Apollo 11, when he knew that he would never fly again due to his iconic status? He had pushed to be number one all his life, and then “Alexander looked about him, and wept, for there were no new worlds to conquer”.
There is also the argument to be made that pilots are more disciplined than geologists and engineers.
I think your quality control would fellate with great allacrity.
There has to be people willing to do a one way trip. I know I would go even knowing that there would be no way to return. Or, perhaps volunteering for a one way mission would cause me to automatically fail the psychological testing.
Yep.
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I found a copy of The Martian on Ebay that I could afford.
Where the guy abandoned on Mars burns hydrogen for water and grows potatoes.
Where the hell does he get the butter, sour cream and chives, hunh?
:dubious:
Right so. We eliminated all that silly life support nonsense and shot our load on a kick-ass Mars probe and discovered: Mars has dirt.
Spock voice: fascinating.
That was the whole rationale of the space colony idea. If you can establish a (nearly) self-sufficient industrial infrastructure in cislunar space almost out of Earth’s gravity well, then everything after that is gravy. The trouble with that is the stupendous upfront cost. Proposals for manned Mars missions since Von Braun’s Conquest of Space have recognized that the more you’re willing to invest in making space travel a regular thing- space stations, refueling depots, lunar mines, massively amortized reusable launch systems, etc.- the greater the return per dollar. It’s the ultimate Giant Economy Size box. But it’s like paying one thousand dollars for one box of cereal, or “only” a million dollars for twenty thousand boxes. A 20X reduction in unit cost isn’t very helpful in that situation.