New Mars Forums

I was initially skeptical when I read the New Scientist article, but after pondering the inner workings of the engine, I'm not quite as sure as I was that it wouldn't work. The fact that he readily acknowledges its limitations (it is only efficient when stationary) is intriguing.

I reckon he's invented the repulsor-lift.

Here's an idea I came up with a few years ago after reading an article on mercury mirrors. I haven't seen this anywhere else yet so I'll release the idea into the public domain. Don't forget where you read it first!

Tethered Mercury Mirror Space Telescope:

By using artificial gravity, the telescope is free to view any location in space with respect to earth.

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Spinning the telescope on a long tether creates a centripetal force which holds the liquid mercury against a circular dish.

The tether is very long so that the rate of spin is extremely slow, thus allowing longer exposures before seeing the effects of motion blur. Also, the tether system will have to be designed so that it does not intefere with the telescopes line of sight.

The circular dish containing the liquid mercury is then spun axially (by either spinning it on air bearings or spinning the whole telescope assembly) at a rate required to attain the desired concave mirror shape.

The wole assembly can be moved about slowly with a small reaction control system to allow it to image any location in space at any time.

Now that the flight risks have become fully apparent, and on the eve of the successful return of STS-114, could this be perhaps the most gracefull moment to finally retire the shuttle fleet, along with the ISS?

What's the likelyhood of hearing something like this from Griffin? He's certainly set everything up for it, what with his SDV plans and all. Will he have the guts?

Atleast with heavy lift we will have that choice. If we really screw up the apollo redux, we can re-focus on Mars efforts without too much extra fuss. But the real question is, what else can we do with a 120MT+ to LEO launch stack when its not required for lunar missions? I mean, the promise about the 40 per year launch rate never held up for the Shuttle, but a cargo-only SDV is a different story altogether. Thats potentially 4800+ tonnes per year! I reckon Griffins got the right idea, making the shuttle system more efficient, not scrapping it altogether.

May I be the first to say how bullsh*t this new CEV craft is.  First off, we shouldn't make a jack-of-all-trades spacecraft, it's just bad principle. Space, as a term of destination, remember, is a huge generalisation. If space is anagolous to the ocean then it would be sufficient to describe the CEV as a boat. It is simply an airtight vessel capable of transporting stuff from one destination to another. Which does nothing at all to describe its capabilities, other than it's capable of being a boat. Is it a short range passenger ferry, a small dinghy, or a disposable life raft, or perhaps a house-boat? The CEV's purpose needs to be set in concrete before we start thinking about the design and funding and such. And what of this nonsense about accelerating the design schedule? Why must NASA insist on a 24/7 human presence in space? Why? Can we even afford it anyhow? I mean look at the year 2013: The CEV will be absorbing maximum funding (operational vehicle or not), the ISS will still be occupied with a full-time crew, all the while the Moon program will be demanding huge sums of money. We simply can't afford all three pursuits. We have to drop atleast one, preferably two. The ISS should go ASAP, so why can't we kill it in 2010, with the shuttle? That way we wouldn't need to accelerate CEV development, which we couldn't afford anyway, and we can put full effort into the Moon-Mars program.

We already have the ISS to hold us back, we don't need the CEV to justify the ISS when it is complete; It'll be just another shuttle. Pointless mutual justification. Kill them both and concentrate on a dedicated 'Moon vehicle', not CEV.

I reckon they drove oppy into the sand on purpose. It somehow seems suspicious...  :;):

GCNR:

I'm being realistic and you know it. I hate this to effect my credibility; but that election reminds me of that South Park episode where they hold a school board election. The candidates are Turd Sandwich and Giant Douche. They were both crap, but atleast we were sure Bush was crap.

I have said this myself in other words, but I feel this point cannot be stressed enough. NASA is an orginazation of engineers and scientists, not visionaries, or as Dook touches on, entrepreneurs. NASA has not even dropped us hints that they plan to look for PGM's, let alone mine them for profit. Honestly, the idea, in todays context, is ridiculous.

Please don't try to justify the lunar return when it is clear NASA's intentions and abilities differ greatly from your own ideals.

Commodore, Mars Direct entails that all the return fuel is made, and the ERV checked, before the crewed hab is launched. So that could never happen. Ofcourse, any number of things could go wrong, but the same could be said of NASA's DRM plan.

Mars Direct consists of the bare minumum of hardware you could get away with, while keeping the crew safe. So if you wanted something with more redundancy, you would have to spend a lot more, but you end up with diminishing returns. Also, by adding redundancy you may also inherently increase risk (by relying on extra docking procedures, etc.). Such is the case with the Design Reference Mission, IMO.

Here's a thought: If you wanted to increase redundancy, why not launch 2 MD missions at aproximately (within a few weeks) the same time (perhaps the first one could be launched at a slightly lower velocity, so that the last passes the first mid-flight). If one fails, the HAB might have enough fuel to dock with the other; the crew would transfer supplies, and land on the surface together in the same hab. Also, by flying two missions together, you could have two teams working together on the same site, and the same advantages might apply on the return leg.

What makes DRM better than MD again?

Cindy, I share your frustration. I think the truth is everyone was rooting for Mars, but when Bush made his speech, and surprised everyone with his Moon goal, we all had to adapt. I mean, at the time it looked like it was either a return to the moon or LEO forever. And now here we all are, trying desperately to convince ourselves that a return to the moon will be okay... Scrambling for reasons and justification.

Damnit! It so frustrating: Why didn't Bush just say 'Mars by 2020'. It would have made so much sense; The MER Rovers had just landed, there was a lot of excitement in the media about a humans to Mars program (Bush's father, afterall, had asked for it back in 1989).

Why oh why...

And now it looks as though a renewed lunar program will significantly delay, or may even kill altogether, a humans to Mars program. As opposed to helping us on the way, as was Bush's real intention.

But Griffin, a common-sense engineer, is in the seat now. So maybe things will change for the better. We'll just have to wait and see.

Damnit GCNR, NASA cannot afford to be dumping half of The Army as you require. They can't and they won't. And if there's not enough dough left over for a half-decent human space flight program, ...well then NASA is screwed. Woe is NASA!

He doesn't need to change his mind. He said Mars, but the moon first, as a 'stepping stone', remember? The debate is not Moon vs Mars, the debate is whether the moon is a viable stepping stone. EELV's only make sense if the moon is the ultimate destination, and I think Bush made it pretty clear that it's not.