New Mars Forums

Good point about the relative merits of advances in materials science, Euler. I see what you mean about the payload mass ratio.
    I guess if you can develop a viable hybrid engine, jet/scramjet/rocket, together with lighter stronger materials for structural components and fuel tanks etc., then the SSTO concept will be realised. But what of nuclear engines?
    If we could produce a Nuclear Thermal Rocket with negligible contamination in the exhaust, would it be light enough to provide the efficiency improvements necessary to make SSTO feasible right now?
    And where might Quantum Nucleonic Reactors fit into the picture? Could they be used as part of a hybrid SSTO engine to improve efficiency?   ???

    Apologies to those who may have covered these concepts in other threads here at New Mars. I confess I haven't been keeping up with every thread in recent months.

    Hi, Rik! Your comments about operational costs are very topical at the moment. I see Lockheed have just done some tests on airbag systems for landing capsules on the ground instead of at sea. This would presumably make capsules more re-usable (less salt water damage etc.) and obviate the need for expensive naval task forces to recover crews offshore.

I believe that's the current state of play, all right.
    Without claiming any expertise in rocket science, I've read enough from various well-informed people to realise that Single-Stage-To-Orbit vehicles are technologically and economically marginal at present. In fact, given the theoretical performance limits of chemical rockets and the forseeable improvements in materials science, I think it's difficult to see any immediate future for the SSTO concept.
    Any improvements in materials would probably be just as advantageous for 'big dumb boosters' as for SSTO vehicles, so those improvements would likely be used to make conventional staged rockets cheaper, rather than to make state-of-the-art space planes.

    I don't know just how cheap rockets could become if they were truly mass-produced(?) but I think access to orbit is always going to be expensive unless we can come up with something revolutionary. Ideally, we will find a way to manipulate gravity, without breaking every rule in the physicists' handbook! But, in my opinion, the construction of several heavy-duty space elevator cables may be our best option, which is why I'm so interested in the progress being made in that department.

    Sorry! I guess I'm getting a little bit off-topic here.   

Thanks for asking about 'that penny' but I haven't seen it for many years. I always assumed my mother had it and, when she died, that it must have gone to one of my nieces in Ireland.
    I'll ask 'em one day.   

Ammonia or no ammonia, I still think there's life on Mars.
    I'd be happy if Mars were sterile but I believe the chances of that are slim. I can't prove a thing, of course, but the balance of probabilities persuades me.
    Time will tell.
                                     

RATS!!!    :bars2:   

Those MERs are wonderful machines all right!   
    They're certainly giving us many more pieces of the martian jigsaw puzzle to play with but, as RobS tells us, we have to be careful not to over-interpret the data. I confess to being a bit of a romantic when it comes to Mars and so I have to keep my enthusiasm in check somewhat!

    Thanks, Rik, for the encouragement about paradigm shifts. I hope any actual shift won't just move us from one stage of frustrated puzzlement to another!   
    That's the trouble with robotic probes; they usually present us with more questions than they answer. If we had humans there, we could modify our 'interrogation' of Mars as we went along, changing the emphasis of the exploration as circumstances dictated.

    I'm still confused about the paradox of a planet which shows so much evidence of massive inundation all over the place and yet has so many areas of olivine on the surface. (Olivine, as you know, is extremely vulnerable to quick weathering in the presence of water, or even ice.) So, while every report about surface water makes me wonder whether one of the MERs might actually stumble across a macroscopic fossil (Yes, wouldn't it be fantastic, Cindy?! ), the wet-Mars/dry-Mars inconsistency keeps pulling me back, like the bridle on a horse!   

    Still, Spirit and Opportunity aren't dead yet and I'm optimistic, as always, that great discoveries are just around the corner.
                                               

Cindy:-

    You said it, Cindy!
    I can't adequately express my admiration for these engineering geniuses who produce such magnificent devices. May their names live on in the hallowed annals of space history forever!
                                            

All good points.
    However, I still think there's a biosphere on Mars, though I won't be upset if I'm wrong.
    My ideal situation is for Mars to be sterile and volcanically active. These two situations are ideal from a terraforming point of view and colonisation/terraforming are my main aims for Mars.
                                                     

Wasn't that the one in the urban myth? You know, the one controlled by a KGB dwarf who went to the Moon one-way, in secret, inside the Lunokhod - a suicide mission for the greater glory of mother Russia?
                                       

Interesting quote, YLR.
    Can you give us a link? I'd like to read the whole article.
    Thanks.   

O.K. GCNR!
    I think I understand your position a little better now.

    As far as the asteroid thing goes, I think our understanding of the structure and consistency of comets/asteroids is lacking. If we're ever to influence the path of one of these critters, we'll need to know them far better than we do now.
    Any attempt at carrying out experiments to gather actual data about their physical characteristics and how they behave when 'provoked', must surely be worthy of support(?).
Personally, I don't care who does it, as long as it gets done.

    And I am filled with admiration for the spectacular skill and intelligence of the NASA workforce. I've been in awe of the American space program since I was a child and any gripes I have about NASA are really only born of impatience because they're not moving fast enough for my liking! But then, if they had 20 NASA scientists on Mars today, I'd probably want to know why there weren't 40!!   :laugh:

    Having expressed my admiration for NASA and America's space achievements, though, I'm still keen on Europe getting into the act. I think the Europeans have a lot to offer and they've made good progress lately, even though they still lag well behind the U.S.
                                           

Thanks, Rob.
    I've always been impressed that we have among our number someone of your calibre, who was involved in the Viking missions. They were, after all, groundbreaking missions which revolutionised our understanding of Mars.
    For this reason, among others, your opinion in all this is important to me as a barometer of how much the new data about Mars and terrestrial extremophiles may be altering our views of the life-on-Mars question.

    Even since I registered at New Mars, about 2 years ago, the attitude to 'life-on-Mars' has changed. I believe most of that change has happened since the MERs have been doing their thing at Gusev and Meridiani.
    In the early days, I could feel the coldness in the air when I suggested Mars was alive, not dead. It's becoming much easier to raise the subject lately!