Two new interesting news items, both discovered via Synthetic Aperture Radar (SAR) scanning by orbital space-vehicles. First target is the Moon… Water Ice Found on Moon’s North Pole …some 600 million tons of the stuff, found as ice a couple of metres thick lining the floors of 40 or so small craters around the Moon’s North Pole. The India moon-probe Chandrayaan-1 carried an American SAR instrument into Lunar orbit and successfully scanned the Moon before the probe packed it in. Now data analysis is producing these sort of reports, more which will appear thanks to the 41st Lunar & Planetary Sciences conference that is currently happening in the USA.
The next target is Mars… JPL News Buried Martian Ice …which has even more ice present than first imagined, buried under regolith so it doesn’t evaporate away to the Poles. Very handy for future colonists. Discovered via a Shallow Radar system on the Mars Reconnaisance Orbiter mission. A lot of it is very clearly associated with erosional basins, thus some kind of water/ice based weathering created the features and eventually trapped the ice there.
Buzz Aldrin has recently come down on the side of the Obama administration’s axing of the “Return to the Moon” program GWB began in the wake of “Columbia” burning-up in 2003. For a Moon-Walker that might seem a strange position to take, but Buzz’s position is more ambitious than the apparently “purposeless” (i.e. non-vote related) program of NASA. He wants commercial space-vehicles servicing the ISS while NASA builds a real space-ship, the XM, a space-ship ultimately bound for Mars. And he thinks we should use all the remaining bits of Shuttle etc. to do it.
I agree with the spirit of his plan, but I have one reservation. The Moon has a long-term resource that Mars doesn’t seem to have. Mars is the destination for colonization and ultimate transformation, sure, but the Moon has about ~2.5 million tons of 3He in its regolith, and I believe that will be vital to building high-speed fusion propelled space-ships. But we need to “ground truth” those proposed solar-wind deposited resources of the Moon. And there will be more than just 3He, which is very rare. All that lunar hydrogen, bound up as water-ice, will contain deuterium, another fusion fuel and vital for CANDU natural uranium reactors.
But here’s where Mars has an advantage – deuterium. Mars is enriched in the stuff, at least the water we can see is. Ideally we need both worlds, something only serious propulsion systems, like fusion, can give us.
Adam, I would agree with you that Mars should be colonized but that we should go to the Moon first. But I say this for a different reason. Namely, that we need an off-Earth, self-sustaining colony as a back-up in case humanity destroys itself. Please allow me to ask you some specific questions:
– Do you believe that it is possible (let’s say 2% or greater) that someone will develop self-replicating technology sometime around mid-century which could pose an existential threat? Perhaps it would be a self-replicating echophagic chemical, nanosomething, accelerating AI, or an artificial bacteria to which we have no immune defense against?
– Do you believe that it is faster / cheaper to colonize the Moon than it is to colonize Mars?
– Do you believe that it is possible within reasonable budgets to construct a self-sustaining lunar base before about 2060-2070?
If you answer yes to all three, then, wouldn’t the survival of mankind take priority over He-3 or deuterium? Shouldn’t survival be the driving motivation for what NASA should be doing next?
Note: Both motivations to return to the Moon (survival vs development) share a lot initially in terms of architecture. But, without the survival motivation, we might be diverted to Mars (national pride instead of development or survival) with a pretty significant delay before achieving a colony. Also, a lunar mission based upon survival would probably differ on what we’d do once we arrive (e.g. transporting carbon & nitrogen or the equipment to extract those ppm from the regolith).
> Point (3) I’d say definitely. Once an efficient Cis-Lunar transport system is available, then a self-sustaining base is a reasonable goal.
I’d like to explore with you sometime what would be the minimum requirement necessary to achieve a self-sustaining lunar base — especially if the cis-lunar portion of Constellation really is cancelled. i.e. would it still be possible with Falcon 9 Heavys, for example and, if so, how?
> Point (2) I am not so sure. The Moon is closer in raw travel time, but further away in some respects because you can aerocapture/aerobrake at Mars
Yes, I believe that the fuel requirements for Mars is actually less than for the Moon because of aerobraking. But Mars has the following problems:
– every-2-year launch window,
– significant time delay for teleoperated robots,
– radiation exposure in transit,
– fear that astronauts in precarious situations (e.g. Apollo 13) couldn’t return quickly, and
– having to carry months of life support.
I just don’t see aerobraking and atmospheric resources as being overriding advantages compared with the Moon if speed of achieving a self-sustaining base is a strongly held goal. However, if we don’t have an easy way of reaching the lunar poles then this changes the equation considerably.
> Self-Refuelling NTR
Sure, but I am imagining that this will take lots of dollars, time, and overcoming anti-nuclear opponents. Right now I’m looking at a plan B if the cis-lunar part of Constellation is cancelled in favor of a much later Mars mission.
> the rotten diurnal cycle
Sure. But how much of a problem is a 2-week night? Is it an issue of power? Couldn’t this be solved by operating near peaks of eternal light, storing electricity, nuclear power, breaking H2O into H & O and then using that energy during night?
Or if the problem is that it would mess with people’s circadian rhythm, then basically the colonists would be sort of like shift workers or submariners for half the month.
Or is the problem of equipment fracturing with the drop in temperatures? Is the diurnal cycle a deal killer?
> The biosphere has experimented with replicators for 4 billion years and still hasn’t produced “One to Rule Them All”
Yes, and I would add that lightening has experimented with basic chemistry to try and create a self-replicating chemical up to some size. But so far it has not created Grey Goo.
But, I think that the difference is that mankind can experiment in a different domain than the biosphere has. Mankind has manufactured many devices that nature has never created. For example, the tree of life gets nowhere close to being able to produce a Toyota Prius. Likewise I wonder if someone with a desktop atom-by-atom manufacturing device could produce a self-replicating chemical which has no competitor, nor predator, nor logical reason why its limiting reagent (e.g. CO2) shouldn’t be used up. I just really don’t know if anyone knows for sure whether it’s possible or not. At any rate, it would be prudent to establish an off-Earth, self-sustaining base as a first priority. Right now, I think that we could establish one on the Moon before we could establish one on Mars.
Hi John
The runaway replicator that eats carbon dioxide… didn’t think of that one. Good points John. Still think Mars is better, but then the Moon is airless and that would limit runaway replicators.
“Replicator” typically brings to mind either an appliance-sized something from Star Trek or at least a nanodevice using wheels, conveyor belts, robotic arms, etc which was designed by an engineer.
A self-replicating chemical typically implies something not much more than a few dozen atoms. Have all possible chemicals up to that size been created naturally? I don’t know. A chemical ecophage would have to be simple enough (I think) that it could easily pull together another copy from simple? reagents readily available in the environment. Now scientists have created self-replicating chemicals but they only operate in unique environments such as a beaker with high concentrations of their reagents. Then, is there something about the nature of nature which prevents something from going to completion without using up all of one of its reagents? In chemistry, the answer is essentially no. But in biology it seems to be yes unless a niche (whatever that means) is considered to be a reagent.
Hi John
There’s the old “andromeda strain” dodge which creates new mass from energy, but that seems excessively difficult to be true. Or “Ice IX” which is a fictional solid phase of water that turns Earth into a desert in a Kurt Vonnegut novel.
> but then the Moon is airless and that would limit runaway replicators.
Lack of air means that it couldn’t spread by air. True. Good point. But what do you think about the likelihood of a replicator (reproducer):
1) leaving the Earth,
2) surviving transit to the Moon vs Mars,
3) burning up in the martian atmosphere vs burning by a hard impact on the Moon
4) surviving long enough to get into a habitat
OK, I feel like I’m speculating well beyond my pay grade here…but here goes…
1) Leaving Earth – If the replicator was a chemical then I could imagine one of them being blown to a high altitude and then being blown into space by frequent, high-altitude meteor strikes. If it was a nanodevice even at the massive weight of a dust particle, I still think that it could be blown to a high altitude. So I’m guessing that it wouldn’t take too long before either would leave the Earth.
2) Surviving Transit – Mars is a lot further away and so solar radiation would have a much longer time to sterilize the replicator. I’m guessing that a single strike by a solar proton would destroy either a chemical or a nanodevice. Furthermore, the orbit of the replicator could only? be changed by the solar wind but the solar wind would destroy the replicator, yes? Certain bacteria survive in space but I think that the reason for this is that one solar proton doesn’t necessarily kill the bacteria and bacteria has repair mechanisms which, presumably, a chemical or nanodevice wouldn’t have. If the replicator were in a piece of rock blown up by an asteroid then it could well survive in space. But, I’m guessing that rocks being blown off Earth to escape velocity happens maybe once every 100? years (e.g. Tunguska-level ground strike). So, it seems to me that transit survival is hard to achieve. But, if possible…
3) Atmospheric vs Ground Impact – Impacting the lunar surface would deliver the energy over a shorter period of time than through the atmosphere. Again, it seems as though free-floating replicators (whether chemical or nanodevice) would reliably be destroyed either way. Again, only a replicator in an ejected piece of Earth would survive either.
4) Surviving Long Enough to Get Into a Habitat – This is particularly interesting. IF we establish a self-sustaining off-Earth colony before replicators are created then we have the protections of 1), 2), and 3). But if we were to only have an underground Earth bunker then leaving the Earth without carrying contamination would, in my opinion, be almost impossible.
If we already had a self-sustaining off-Earth colony when replicators were created on Earth, then I would imaging that it would be at least years (maybe decades, centuries, or never) before the replicator made its way to the Moon or Mars. If it were to survive after reentry (Mars) or impact (Moon) then I think it would be iffy but possible that it could replicate on Mars and could easily spread by the wind. But I think that it would go nowhere on the Moon.
My Conclusion – Prudence dictates that we establish an off-Earth colony, really, ASAP. I still believe that a self-sustaining colony can be more quickly established on the Moon than Mars. It seems to me that most people agree that a lunar base can be established quicker, safer, more cheaply (even taking aerobraking into account). I would go a second step and say that the relative resource deficiency of the Moon vs Mars (e.g. carbon & nitrogen, volatiles only at the poles) can be overcome faster than a martian effort. Just my current understanding.