New Mars Forums

I would like to see all the Al Qa'eda leadership taken into Low Earth Orbit so they could look down at our beautiful blue planet.
    I want them to see what the astronauts often talk about. I want them to see a world with no visible evidence of political boundaries, where we all depend on Earth's bounty for our survival and on each other for a peaceful life.
    Maybe they'd come away from that with a different point of view(?).

To an extent, I agree with Clark's reasoning in that it seems sensible to keep the astronauts in a high gravity situation for as much of the mission as possible.
    In view of the probability (in my opinion) that the astronauts' bodies will quickly lose high-g conditioning as soon as they take up residence on Mars, I wonder whether artificial gravity set at a level higher than 1g is really necessary. Whether you've been in 1g or 1.2g for the six month outward voyage, you'll feel like a 'superman' or 'superwoman' for only a limited time when you arrive - perhaps only a week or two.
    And besides, I'm having enough trouble talking people into 1.8 km of cable, 1 rpm, and ONE g !! Never mind upping the ante to 1.2 or 1.3g !

    I think the reasoning behind creating only 0.38g on the way to Mars is two-fold: Firstly, it looks technically easier to do than creating a full 1g and saves the weight of a longer cable and, secondly, there may be a valid argument that the astronauts will be better 'primed' to gauge and control their physical actions and reactions more accurately if they're acclimatised to martian gravity before they get there.
    But this scenario is usually presented as part of a bigger picture which includes a return flight to Earth with no rotation at all. In other words, it's a bare-bones compromise to ensure the explorers can function adequately when they reach Mars but which pays little attention to their long-term well-being when they get home.

    If I read Clark's attitude correctly then I agree with what he's saying, that a full 1g (at least! ) should be provided almost all the way to Mars. Rotation should be halted at least 48 hours before arrival to allow for the period of space sickness which afflicts more than 50% of astronauts when they hit zero-g.
    Rotation should be arranged for the return trip also - gradually increasing from 0.38g to 1g during the course of the journey.
    If the above plan can be implemented with a rotation rate of only 1 rpm (i.e. with long cables), then I believe we'll have done everything feasible for the physical well-being of the crew.

    Aside from the weight of the cable, spool, and small ion thrusters for spinning-up and spinning-down, I don't see any significant problem with this scheme and I believe it is in the best interests of the people we send on these missions.
    An added advantage, if sufficient warning can be supplied, is that the counterweight could be used as an additional shield against solar flares if it could be manoeuvred into the right position in time.
                                               

I've always wondered what it would be like, Cindy, to stand on Mars and realise how much smaller the Sun looks.
    I think that difference, plus the closer horizon and the lesser gravity, are the things which have always made me yearn to go to Mars. (And I use the term 'yearn' without exaggeration - it's the damnedest feeling to want something so strongly without really knowing quite why! There must be something mystical about that planet.)
    As I've said before, I imagine a time when we can walk unprotected on the surface of a Mars transformed into a new home. I can almost feel the cool sea breezes and the salt spray of a sandy beach beside the northern ocean and I can feel the muted warmth of a smaller gentler Sun with its softer light.

    It's been a while since I've pictured that scene.
    Thanks, Cindy, for jogging my imagination back into gear!
                                                     

Things are shaping up nicely!
    An industrial heavyweight and household name has stepped up to the plate to encourage the future of space elevators. Who am I talking about? Why, none other than that doyen of the world of elevators .. OTIS, no less!!

    Already in the process of creating new and innovative elevator systems for the sky-scrapers of tomorrow, including multi-storey elevator cars, Otis says it can produce low maintenance vehicles for the space elevator in a time frame of just 10 years!
    Apparently their personnel see no technical show-stoppers in the way and seem perfectly confident it can be done.
                                               

    For the full story, have a look at This Site.
    This could be the start of something big.
                                                               

I know we've discussed airplanes on Mars but I couldn't remember whether or not we've discussed helicopters.
    As it happens, other people have certainly been discussing non-fixed-wing aircraft for use on Mars!

    Apparently the thin air and lower gravity make insect-like wing-flapping craft very appropriate. The way an insect moves its wings creates vortices at the wing edges which greatly enhance lift and horizontal manoeuvring.
    But it seems the good ol' helicopter can be made to fly on Mars also, albeit in a somewhat modified form and on a small scale.

    For an interesting overview of work on these two aspects of potential martian aircraft, check out This Site.
                                               

Cindy:-

    You said it, sister!!    :angry:

    [Now do you go along with the death penalty?!!!   ???  ]

I was just about to say the same thing!
    Thanks, Rxke!
                                       

All good points! Thanks again Robert.   

    All this talk may well be moot, of course, since many people are of the opinion that astronauts can withstand zero-g for 6 months and then perform adequately on Mars (0.38g) for 18 months.
    I believe that's probably quite correct, as far as it goes. But then, I look further, at another 6 months in zero-g before a return to full Earth gravity at the end of the mission.
    I honestly don't think the astronauts will be able to make the transition back to terrestrial gravity safely after an absence of two and a half years. At least, not without advances in our understanding of human physiology and the development of appropriate medicinal prophylaxis.

    I happen to think the mastery of the use of 'tethered-gravity' will be no more difficult to achieve than orbital rendezvous techniques were. Where there's a will ... !
    If a suitably low-mass system can be devised, I favour tethered-gravity on both the outward and homeward bound legs of the journey. It was suggested here last year some time that the astronauts could be acclimatised to Martian gravity by slowing the rotation rate in the final stages of the outbound trip. And, conversely, they could be acclimatised gradually to a full 1g during the 6 month flight home by increasing the rotation rate. I believe this is the ideal scenario.

    You know, Robert, with your skills and determination, devising a tethered-gravity system might be a way for you to break into the aerospace business. It looks like a doable project which could be approached in a staged and systematic way, so as not to become unwieldy from a financial perspective. Much of the research could be accomplished before any significant expenditures were required and, basically, it's just a mechanical problem that needs fleshing out and refining. The beauty of it, from your point of view, is that nobody else seems to be doing anything with the idea.

    Imagine the 'RDyck-Tether-System' becoming standard equipment on crewed Mars missions in the next few decades!!
    I, for one, would love to see that happen.
                                           

Yoiks, tally-ho ... and awwf we jolly well go!!!
                                     

Thanks, Robert, for coming up with all the relevant detail!
    I was just going to celebrate the relatively low figure of 2.68 tonnes when I suddenly thought '18,890 lbs ... 2.68 tonnes ... hmmm! That doesn't sound right.'
    Everything looked great up to that point but, tragically, 18,890 lbs is over 8.5 tonnes!! (Don't worry about the last minute slip, I do it all the time.)

    What's important is the unpleasantly large mass of cable for a full 1g. Unless we have very capable boosters for this mission and perhaps a more generous budget, I can imagine a lot of people getting very upset over what they might see as an awful lot of mass to provide the unnecessary luxury of a full Earth gravity.
    Assuming any attempt at all is made to provide artificial gravity, we need to either aim for a lower figure (Mars gravity has been a popular suggestion) or come up with a more efficient cable.
    Does anyone know whether there is any hint of a new material being developed, with a higher tensile-strength-to-mass ratio, apart from carbon nanotubes (cnts) I mean?

    Or should we just be waiting for Hi-lift to sponsor cnts as part of their quest for a space elevator, and then just 'borrow' the technology?! Presumably they'll have a viable cnt material in their inventory within 10 years and that should fit in with a Mars Direct timetable fairly well.
    I have no figures at all but I can imagine a suitable cnt cable for a 1g rotation of the Mars Hab coming in at a helluva lot less than 8.5 tonnes!
                                           

It's good to be skeptical, Josh; Carl Sagan always said we owe it to ourselves to be that way.
    Without skepticism, we start to believe in all the old witchcraft and black magic that kept us in thrall for millenia, before the art of science came along.

    On the other hand, if skepticism becomes too dominant and people are castigated and ridiculed for seeing merit in a new hypothesis or a different paradigm, just because it flies in the face of currently held beliefs, then I tend to shy away from skepticism.
    That kind of skepticism can take away our originality of thought and undermine our ability to imagine and to dream. Science is good at winnowing out the bulldust from the gems in any batch of hypotheses but only the inspiration of the human mind can create those hypotheses in the first place.
    Let's not let anything dampen the enthusiasm of original thinkers!
                                         

All I get is the Elephant's Trunk Nebula.

    It's very pretty but it's not Mars!   

[This isn't the first time I've had trouble getting the right picture. Is there something screwy going on with my server? ]
                                                    ???