Just don't brush your teeth with it....
NASA, in a joint venture with US air force boffins, has tested a new kind of rocket fuel which "has the consistency of toothpaste" and could potentially be manufactured off-planet in remote space outposts. Its inventors say it is also less environmentally damaging than some current rocket fuels when used within Earth's …
Just don't brush your teeth with it....
We havn't even managed to get people to Mars yet and already we are contemplating mining a scarce resource. Ain't people wonderful.
You get all the way they, assemble you little fuel making robot and oops, a parts broken.
Well, nice knowing you....
while i'm aware that burning hydrogen and oxygen - as current liquid fuelled rockets do - produces water vapour as an exhaust...
I was under the impression that hydrogen and oxygen aren't the ONLY ingredients in a liquid fuelled rocket. There are usually various additives and stabilisers etc etc - some of which are extremely toxic, so maybe an ALICE engine could be more environmentally friendly than a "convention" rocket?
I suspect they would get the fuel production working remotely first, before relying on it. That bit is pretty easy, if the right compounds are on the planet.
I guess they'd want to test it out first with one or more robot missions, e.g. to return a sample from Mars, before trusting it for a manned mission. Ideally you'd set up a fuel factory for use by multiple return missions and stockpile fuel ready for the arrival of a manned mission so they'd know they've got the fuel to return before setting off..
Right, so we'll now start mining remote planets for our own selfish ends: given the track record of tearing the guts out of this one, I'm not thrilled at that prospect (no mining pun intended)!
Right, because NASA never carries any spare parts. For anything. Ever.
Seems like quite a clever idea to me.
"We havn't even managed to get people to Mars yet and already we are contemplating mining a scarce resource. Ain't people wonderful." ... By Roger Jenkins Posted Monday 24th August 2009 11:10 GMT
And imaginative too, RJ, and some would even say quite optimistically mad for astronomical funding. And it is as well to imagine that there is a price to pay Martians for their resources too, to ensure that your secretive imaginative technologies are not shared with more than capable competition and engaging opposition.
...Use a MASSIVE bunch of baloons to take the payload up to around 100,000 feet where it can then launch into space with a minimal amount of fuel / thrust?
Rocket exhaust also contains significant quantities of nitrogen oxides formed in the high temperature hydrogen-oxygen flame. These are environmental and health nasties and are also a drawback to burning hydrogen in conventional engines.
And has anyone checked the health implications of nano-scale aluminium particles yet?
You just find a water ice asteroid and crash it into Mars, thus giving you a vast supply of non-native water, thus you don't use a scarce local resource. Actually, you might even be able to put the asteroid into orbit around Mars, if you're worried about the tectonic, or environmental impact of an impact, and the for each ton of water ice you extract from the pole, you lob a couple of tons of asteroidal ice into the atmosphere, it melts in decent and falls as snow somewhere on the planet's surface, and so on.
Now where do we find a water ice asteroid or two.
But really, just how much water on Mars would you use, and how much nano scale aluminium and trace elements like gallium would you need to import to make it in usable quantities, I suspect the latter might be the bigger problem, as by the time you have made a meaningful dent in the water on Mars, you would probably have found enough water ice elsewhere to replace it. Also bare in mind that a lot of it would come back as water vapour, as I assume you are using the Aluminium as catalyst to crack the water into H & O2, and then burning the H and O2 to produce the thrust, with the heat driving the cracking process. The is the issue of pumping exotic oxides of Aluminium into the atmosphere though, which we then breath in, Alzheimer's and all that. Also that you need quite a lot of power to produce the aluminium from bauxite in the first place, assuming you have a handy source on Mars, that's near the Water. To make it economically viable, you would need the sources of materials locally to the production site, as shipping Aluminium and Water to the production site might actually be a tad expensive. It might be Ok for Aluminium if the quantities uses are in parts Per Million, probably better than 1g Al to 1000Kg H2O, can't be pothered to work out exactly.
But if it gets us to Mars and beyond, I thinks it's worth it.
Aluminum is very common on the Moon, and water is very common on Mars. So they're getting there.
And the ballons would rise using..... oh yeah, fuel!
So aluminium is common on the moon and mars eh?
Yes, but it’s tied up in felspars (anorthosite in the case of the moon). There’s plenty of feldspar on earth too, (the pinky bits in granites from Shap – very attractive rock) but do we get aluminium from it? Last time I looked they extracted it from bauxites, using tons of electricity, and bauxites form from rocks weathered under hot wet conditions.
Remind me when the moon last had hot wet conditions will you? Or weather for that matter.
AL + H2O2
Mmmm.. Peroxide Blombed
So, explain to me how the biosphere of these planets is going to be damaged by this strip mining?
Oh wait, there isn't one on either. Ooops!
This seems to me like a more refined version of thermite (relies on aluminium and iron oxide to cause a reaction).
If so, then this should be quite environmentally friendly indeed :)
If you can come up with an engine that burns* Helium** as fuel there might be a Nobel prize in it for you.
*No fusing it, smartarse.
**Like wot you use to inflate balloons for high-altitude work like, say, carrying something up to 100,000 feet....
The trouble is, you let go and... it falls back to earth.
If you want it to escape the earth's gravity you'll need to accelerate it to escape velocity (~25,000 mph), and that's a lot of thrust. The 100,000 ft starting height doesn't help that much.
Roger, if we're going to exist off this planet at all, we're going to have dirty our hands by "mining scarce resources" in the process. The alternative is to remain planet-bound and go through one Malthusian mass die-off after another until we finally grind ourselves down to a miserable extinction; if there's one thing we can learn from our own history, it's that we are not a species which will be satisfied with anything in between. We're not going to go back to our environmentally-sustainable hunter-gatherer prehistory, because we *can't*, any more than you can go back to your three-year-old self by sheer force of will. So we're left with one or the other, expansion or extinction, and mood disorders aside I know which *I* prefer.
And goggyturk's right, anyway: anything that once lived on the Moon died very shortly after that celestial body calved from our own planet and shed its atmosphere, and anything that still lives on Mars is either microscopic, or far underground, not interested in visitors, and not dependent on water to survive -- if it were anything more obvious than that we'd *know* it by now, and if it were dependent on macroscopic water for survival then it would be long dead by now, assuming you don't want to join the Hollow Mars Society and postulate on no evidence at all that that planet's crust is floating on world-girdling underground oceans.
So aside from the whole environmentalist insistence that humans are by definition unnatural and that a human so much as looking cross-eyed at a blade of grass is viciously raping the biosphere for selfish gain, what are you left with, Roge? The idea of mining Mars for water ice and extracting vapor from the atmosphere is something you find distasteful, is it? Fine, then -- don't go.
Altitude helps, but you still need speed to get into orbit. Lots of it. Which needs a great deal of fuel.
..getting a smelter, electrodes and a fair sized powerplant shipped to the site might be.
The anodes currently are made of carbon which is eroded by the process of sequestering the oxygen as CO2. The only practicable solution would be to have an electrode manufacturing facility on site. Raw materials to feed it? Perhaps a forest in a dome converting the CO2 to a usable source of carbon? And the water comes from?
Add to those factors the comparatively tiny amounts of aluminium that will become rocket fuel and the talk of off-world manufacturing is just a load of lip-flap to mollify the environ-mentalists who would be screaming about how bad aluminium production is.
So, where can we get black powdered aluminum so we can start experimenting ourselves, sounds like a good project for model rocketry buffs everywhere. Not those puny Estes things, but these:
So, do you suggest that once we run out of raw resources on this planet, we should just curl up and die, or more likely, go backwards in technical evolutionary terms to the stone age?
Fuck off and die you morons, I vote we mine Mars dry [careful with the moon, what with it's effect on tidal forces, etc, mind]
Many people don't seem to realise that most of the cost of getting something into orbit isn't the vertical hike of 200 miles or so, but rather getting to a horizontal speed of 17,000 MPH to achieve orbit and not fall back to the ground.
Raising a spacecraft to 100,000 feet using balloons would impart approximately 1% of the final energy it would need to achieve orbit.
This why the Virgin Galactic(tm) trip will be so cheap: they don't actually get you to orbit.
My idea is to send robots to Mars to make a rocket engine (and fuel of course) that pushes Mars closer to Earth... in fact, they should push it into one of those binary orbit things.
Then we can easily take all its resources and dump our rubbish there.
Once its f***ed we blast it out of the solar system.
...isn't this part of the plot from Total Recall?
Getting to 100,000 feet is cheap. Accelerating to orbital velocity is expensive.
Before launch, the shuttle and boosters have a mass of 2030000kg. Lifting all that to 30500m requires 607GJ. (Slight over estimate because you would not need a full external tank if you start from 100,000 feet.)
Without the external tank and boosters, the shuttle has a mass of 109000kg. Magically accelerating only that to the velocity of the international space station (7680m/s) without any rocket fuel requires 3200GJ. In real life, over 90% of the initial thrust is used to accelerate rocket fuel. This percentage falls as the fuel is burned, but you need much more than 3200GJ when you include accelerating some of the the fuel to some of the final velocity.
You might save 5% on the cost of a space shuttle if you had a free ride to 100,000 feet. You are looking for a payload of about 200,000kg. Here is what is/was/might be available:
Payload: 160,000kg Currently incomplete and out of money.
Payload: 40,000kg. Zeplin/helicopter hybrid currently under development.
Payload: 83,000kg. Currently in pieces under the sea.
Payload: 72,000kg. Currently in pieces under the sea.
Payload: 10,000kg. Currently not functional. (LZ-130 scrapped after 129 went down in flames)
Payload: 2000kg. The biggest I could find that actually flies today.
I doubt that any of these could get close to 100,000 feet.
I read it as getting the oxidizer on the moon/Mars, not necessarily the aluminum too. Not having to carry the oxidizer from Earth is a win; figuring out a way to mine aluminum just makes it better.
And the comparison shouldn't be with hydrogen/oxygen liquid fueled rockets, but with kerosene/oxygen and aluminum perchlorate sold rocket fuels as used in the Shuttle SRBs. Perchlorates are nasty and quite persistent in the environment.
I also have to agree that mining water ice is not a big threat to Mars. Now when we start strip-mining it, then maybe we ought to think a bit harder. But we've got a ways to go before we start launching Caterpillar 797s to Mars.
You'll get some nitrogenous waste out of *any* rocket, because they all emit hot plumes. However, the main emission of the shuttle's three main engines is pure water.
On the other hand, the shuttle has a couple of filthy solid boosters slapped on the sides, which are responsible for all the smoke you see on take-off. It wouldn't be hard to improve on that.
Back on the first hand, unless you are planning a truly awesome extension to NASA's budget, I don't think the environmental credentials of a few rockets will make much difference to the planet..
Rockets won't cut it for a long-term solution.
Fortunately, nature has already come to our help: the caldera of Olympus Mons is almost in outer space; the rim is 76,000 feet higher than the surrounding plains. Why not just make a gigantic Gauss gun? Accelerate across the caldera, ramp up over the rim and WHOOOOOOOSH! into orbit. At the very least it would be a great way to get bulk cargo into space to construct an interstellar craft.
Now, as far as ALICE goes, I noticed it does burn very very fast (the commercial engine, probably an Aerotech motor, had a burn time probably 10x longer) and so while the THRUST is great with ALICE the IMPULSE is not so hot. This is backed up by the comments at the end of the video where someone commented they "hoped it'd be higher" or something like that.
Contrary to some reports most non-solid and non hypergolic propellants are actually pretty cheap. Liquid oxygen is less than 10c a lb in bulk. Known liquid fueld or cryogens (Methane, Propane, RP1) are all in the <$1/lb range. Solids and hypergolics are expensive because they are either treated as explosives (solids = fuel+oxidiser. If they start to burn they are likely to keep burning and some of them are *big*) or are toxid and / or carcinogenic (Petrol toxicity c1000ppm. Hypergolic fuel c 0.5ppm. Hence $70/lb, hazmat plan and team, armed guards etc)
On a practical engineering point. Phase changes *always* cause trouble. Water expands on freezing (like Silicon but unlike most metals) while exerting substantial (pipe cracking) levels of force.
The $64 question. What's the Isp? If its > c256secs at sea level (Shuttle SRBs) it might be a candidate for SRB propellant replacement (Yes I know the Shuttle is due for the US scrappage scheme. Check the storage requirements placed on prospective acquirers). I have found no mention of this and probably will not have due to this being USAF funded and current ITAR rules being bonkers.
The original In-Situ-Propellant-Utilisation scheme Bob Zubrin proposed planned to use direct electrolysis of CO2 (present in very large quantities in the Martian atmosphere and available by heating carbonate rocks on the Moon) to get Oxygen and Carbon Monoxide. No phase changes, fairly simple seperation but little database on burning CO as a fuel in rockets (but substantial industrial experience on earth).
OMG how would NASA *ever* manage to figure out how to burn a near cryogen (81K ,Vs 92k for LOX and 18K for LH2) with it?
It is likely to be more ozone friendly than most present SRB fillings at it should not release Hydrogen Chloride and hence Chlorine. The NOx compounds released happen whenever any hot gas flow mixes with air.
So *potentially* useful as an SRB filling replacement if it has enough Isp to do the job and you don't mind the short shelf life. A fairly epic fail on the ISRU front. Complex trouble prone engineering with multiple phase changes as standard.
On the plus side its given some engineers a real taste of real world engineering and an actual real result. If only UK universities did as much (although I think Salford may do something).
Mine will be the one with a copy of Sutton in.
Is helium not a fuel then?
Just because your not burning it, you'd still be using lots of it to fill the balloons which will then be lost into the upper atmosphere where it escapes to space. Helium actually being a relatively rare resource on Earth.
Depends on the liquid fuel combo used. Some rocket engines burn pure liquid hydrogen and liquid oxygen. (no additives needed) Some burn rocket grade kerosene (RP-1) and liquid oxygen. Some burn hydrazine and nitrogen tetroxide, which is nasty stuff. The later, and other hypergolic fuels like them, are probably the one you're thinking of when you say "extremely toxic" and are often used in upper stages or thrusters. This isn't by any means an exclusive list of fuel combinations. You might find one or more of these combined together in separate stages on one vehiclet.
The correct term for Helium would be a consumable. It does not burn but probably would escape the Earth.
"Rockoons" (rocket-ballons) have been proposed regularly since the 1950s. Some have flown.
The problem is this.
Balloon carries big rocket up to altitude (this allowas a *very* big expansion nozzle on the engines which improve Isp quite a lot. At sea level the final pressure inside the nozzle would be so low it would trigger massive shaking and destroy itself)
Balloon looses huge portion of mass balencing the lift gas.
Balloon goes into sudden fast ascent
Skin tension rises to bursting levels
Gas vents fast enough to stop it and balloon goes into dive.
Gas does not vent fast enough and ballon bursts.
If it were hydrogen it could be burnt off (and hydrogen is cheap and used in high altitude weather ballons regularly)
Helium is not that rare. Most Helium in the US comes from collecting it at oil wellheads in Texas where it exists with the oil in reservoir strata. This was the supply Germany wanted to use to gas the Hindenburg which the US refused to supply and which caused the switch to Hydrogen.
On a general point. Water is quite rare and should be conserved. It contains hydrogen, which on planets (which are what people tend to prefer not interplanatary or interstellar space) people might live on is rare. Hydrogen is akward to store in pure form and difficult to seperate in compounds (unless you have a compact nuclear reactor handy). Probably best avoided as a rocket fuel.
"Careful with the moon."
Great, now all I can think of is Praxis...
We know less about the earth's oceans than we know about the moon/mars. It doesn't need all sorts of boffinry and is more meaningful.