Wikipedia:Reference desk/Archives/Science/2017 December 24

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December 24[edit]

Military presence on the moon[edit]

I realise this might be taken as asking for speculation, but it's actually asking for facts. I'm trying to work out what advantage a country could gain from having a military presence on the moon. Surely it's too far away for any sort of response to intercontinental threats, and not really suitable for surveillance of enemy nations. Maybe it's some sort of psychological thing? Wouldn't the cost and complexity of establishing, and maintaining a defendable military base rather than just a scientific moon base far outweigh any advantage? Thanks in advance 49.197.84.151 (talk) 04:35, 24 December 2017 (UTC)[reply]

I can’t think of any advantage; and even if there is one, I think it will be outweighed by the cost and complexity. Dolphin (t) 04:44, 24 December 2017 (UTC)[reply]
You can't be directly above latitudes with an absolute value beyond the maximum lunar inclination plus the Tropic of Cancer number plus the Moon semi-diameter. Is there any advantage to that? Sagittarian Milky Way (talk) 05:23, 24 December 2017 (UTC)[reply]
I could see where a military presence might be needed to protect a scientific outpost to prevent it falling into the hands of an (earth-based) enemy. McMurdo Station, a scientific base in Antarctica, has a significant military presence with flights to and from Christchurch, New Zealand. Akld guy (talk) 05:27, 24 December 2017 (UTC)[reply]
The US Army considered a Lunar Military Outpost: Project Horizon2606:A000:4C0C:E200:B8D8:3FE9:323E:5312 (talk) 05:59, 24 December 2017 (UTC)[reply]
One advantage that is often very underestimated, especially regarding military forces, is prestige. According to historians this already played an essential role in the Space Race in the 1960s, between the Soviet Union and the United States. --Kharon (talk) 06:01, 24 December 2017 (UTC)[reply]
(edit conflict) Back in the good old days of Project Horizon, the stated purpose was to:
"...develop and protect potential United States interests on the moon; to develop techniques in moon-based surveillance of the earth and space, in communications relay, and in operations on the surface of the moon; to serve as a base for exploration of the moon, for further exploration into space and for military operations on the moon if required; and to support scientific investigations on the moon."
The first part of that was made redundant my the Outer Space Treaty, the surveillance and communications are better served by satellites these days (remember that Project Horizon was before the miniaturization of electronics and the computer revolution; the assumption was that surveillance and communications would have to be manned), and most of the rest was covered by the civilian Apollo program. Other military projects involving the moon, such as the Lunex Project and Project A119 had similar goals and/or was meant as technology demonstrators and/or a show of force.
One could view the moon as the ultimate high ground, the control of which would be a morale booster more than a practical issue (even more so today than in the fifties). Arguably satellites have made a military moon base redundant, doing the missions envisioned for such a base back in the day cheaper, better and with less risk. WegianWarrior (talk) 06:11, 24 December 2017 (UTC)[reply]
The Moon is a Harsh Mistress is instructive. If you want to take out a city on Earth, all you need to do is point a chunk of rock in the right direction. No current weapons, including missiles, can reach the Moon, so you'd be impervious, at least on the Moon. Of course things are a bit different if we're talking about an Earth-based power with an outpost on the Moon, but this is all hypothetical. The Moon would also make a good staging ground for interplanetary travel. --47.157.122.192 (talk) 07:17, 24 December 2017 (UTC)[reply]
I can't see any particular use. However a lot of sci-fi has bases on the moon either for attacks on earth or to defend earth. In Captain Scarlet and the Mysterons the defence forces against attacks by the Mysterons of Mars are based on the Moon, and there's a point there because launcing the Angel interceptor from Earth would take a lot more fuel. Dmcq (talk) 10:09, 24 December 2017 (UTC)[reply]
Water on the moon is a key resource for developing affordable interplanetary operations and eventually industries that would rain down minerals on their owners. Whoever controls a few craters near the lunar poles controls the solar system. China is putting a lot of effort into getting to the Moon presently. If you watch a Chinese propaganda film like Beyond Skyline or Valerian (film) you'll see the China-to-the-Moon theme featured prominently (AFAIK all films now are 15-20% propaganda by budget... just a question of which government pays for it). With every American director likely to face sexual allegations if they haven't already, you can expect to see a Chinese moon landing in practically any sci-fi film you watch for the next 3 years or whatever it takes them to get there. Of course, "dropping rocks" on Earth is not that simple; some kind of fancy railgun or other launching system is implied, which is either very vulnerable or very sophisticated engineering to dig out on the moon (though it does have lava tubes, if there's one in the right place...) I think the most relevant military force involves the ability of one country to "claim" the resources and then beat off potential competitors on the Moon, perhaps in what would nominally be a proxy conflict between supposedly independent corporations or entities. Wnt (talk) 10:09, 24 December 2017 (UTC)[reply]
The Moon offers a selective advantage that the big powers cane exploit but smaller powers cannot. So, as the technology gaps shrinks and e.g. countries like Iran can launch satellites, the big powers cannot count on certain military advantages they used to take for granted until recently. E.g. in case of war with Iran, Iran may well be capable of destroying GPS satellites, or triggering the Kessler syndrome by destroying a big satellite like Envisat: "A collision between a satellite the size of Envisat and an object as small as 10 kg could produce a very large cloud of debris, initiating a self-sustaining chain-reaction of collisions and fragmentation with production of new debris, a phenomenon known as the Kessler Syndrome."
E.g., the Moon can be used for hosting back-up communications facilities in case all the low Earth-orbiting satellites are destroyed. The Moon can also be used as a covert construction site. Here one can exploit the fact that the Moon has no atmosphere, allowing transport of materials and equipment from a space-station and the moon and back using micro-rockets. This would allow components like computer chips to be manufactured on the Moon and transported to the space-station covertly. Count Iblis (talk) 12:27, 24 December 2017 (UTC)[reply]
  • The Moon is a Harsh Mistress scenario mentioned above is quite relevant. "The military importance of high ground has been recognized for over 2,000 years, citing early examples from China and other early-dynastic cultures who regularly engaged in territorial/power struggles." See also, railguns, which, one presumes, are more effective and easier to construct in vacuum and low gravity than artificial naval islands in the South China Sea. The moon is essentially the top of the tallest mountain on earth. Consider that Robert A. Heinlein didn't write from ignorance. He graduated from the US Naval Academy, took graduate classes in physics and mathematics and was well-versed in ballistics. μηδείς (talk) 18:00, 24 December 2017 (UTC)[reply]
I don't deny the scenario but I think that some of the drawbacks might have been left out to make the novel seem more persuasive. I mean, lunar escape velocity is low, but it is much harder to have lots of power on the Moon. Certainly coal and wind power aren't happening! But using solar panels means having large swathes of expensive electronics exposed to the Sun, or to any microwave or laser projector the enemy might momentarily make much brighter than the Sun. And throwing rocks is... well, still just throwing rocks, no matter how big they are. What are the odds you can precision-guide those meteorites to a target? It has to be a "strategic bombing" i.e. indiscriminate bombing campaign, something which by modern standards would certainly be presented as a war crime. Why not just use a nuke designed for reduced fallout, or if you can manage it an antimatter bomb or induced gamma emission munition? Or if you're serious, designer biological weapons, which offer the best chance to have mass casualties but still be creative and even quite selective. Though I think the biggest threat may be coherent terahertz ... based on some very rudimentary publications from a few years ago, I'm thinking ongoing research might displace particular proteins from the chromatin of the victims, cause custom syndromes, identify them by DNA sequence remotely and harm only the specific 100 million people the software doesn't like, each with different symptoms, from drone or satellite emitters. Cell phone cancers are for ham-handed emitters in broad ranges of frequencies. Or... well, you get the picture, and I haven't even resorted to weapons people actually use yet. That we know of. (What did they do at the U.S. embassy in Cuba?) I think military on the Moon is mostly useful ... on the Moon. Identify its saleable resources and you identify how people will fight over them. Wnt (talk) 02:04, 25 December 2017 (UTC)[reply]
In the book, the Loonies use nuclear power, and they built their backup launcher underground in a secret location. Precision targeting of rocks is not a major technical problem: orbital mechanics is a well-understood discipline. The big problem is that a kinetic strike from the Moon is not a quick-response weapon. The shortest feasible trajectories take a day or so and a high-mass precision strike to a high latitude location will take more than week. The other problem is that keeping a lunar location secret is a lot harder today than Heinlien thought it would be: he did not envision our ability to launch huge numbers of highly capable surveillance satellites. -Arch dude (talk) 06:13, 25 December 2017 (UTC)[reply]
Orbital mechanics, yes. Piloting a large, heavy rock through Earth's atmosphere to a precise location as it melts and ablates? That's where I have the problem. Nuclear power on the Moon is certainly conceivable (indeed, helium-3 is supposedly a resource to be harvested from it, though I have no understanding how the hell anyone would collect it), but think of all the infrastructure you've added up - mining isotopes, building nuclear reactors, digging a giant underground tunnel. And the same orbital mechanics that tells where the rock goes certainly tells exactly where it came from! Which makes that infrastructure vulnerable. Note that small neutrino detectors are finally possible (or at least, finally public) [1] so the nuclear power plant can also be detected directly, wherever it is. Also, the transmission cables ought to stick out like a sore thumb electromagnetically compared to TMA-1, say. And I really doubt a retaliatory nuclear strike on the Moon would be viewed (at least on Earth) as negatively as a terrestrial nuclear attack ... and such missiles would come pre-loaded with reflective shielding and lots of chaff to make sure the "Loonies" can't really stop them. All in all, I think if they even tried to do a North Korea program with rocks, they would be viewed as remote, devoid of normal political protections, and as megalomaniac astronauts who are ungrateful, while being very easily observed, making some kind of pre-emptive strike uncommonly likely before they were even ready. (Yes, they might have dual-use railguns in advance, but for shipping commercially relevant amounts of metal ore, not giant city-killing asteroids. They could be a nuisance with those, a West Bank grade nuisance)
By contrast, war on the Moon seems near inevitable. First you have some lobbyist who persuades a government to recognize his claim over some part of the Moon, like Obama's commercialization of asteroids. At first nobody believes it is valid. The boundaries are made up ad hoc -- if a rocket at the time has a 6-km landing ellipse, maybe he claims 50 miles radius "just to be safe". Some figure, minutes or months, is made up for how long after a human astronaut leaves the base shouldn't legally be interfered with. Fast forward a few decades and three or four players have joined the game, accepted those rules, they have little aluminum huts all over the moon where a single human astronaut sleeps for four hours every lunar day to keep the claim up. And obviously, it would be really really nice for one of the competitors if he had some accident while driving around and couldn't keep to schedule. Wouldn't be troops causing the accident, more like Russian tourists in the Ukraine. Then... you get more and more accidents. Now fast forward a few more decades and all those 50-mile boundaries are the most solemn law and there is a huge portion of the population that sees no problem with their policy of throwing a mother and child out the airlock, after first recovering their air of course, because the unauthorized presence on their land is an unacceptable trespass and a violation of the most sacred and divine law. You can't really do much for people like that ... chop them up, burn the pieces, beam them through a portal to hell into a black hole, and even then, technically by relativity, you've only moved their unshakeable belief into the future. Wnt (talk) 14:05, 25 December 2017 (UTC)[reply]
Leaving out the treaty obligations barring most space-faring nations from making territorial claims to heavenly bodies (including the Moon), there are strong physics-related reasons why it's not worth using the Moon as a military base against the Earth. The Space Review article "Take off and nuke the site from orbit (it’s the only way to be sure…)" deals with them in depth, but basically, a Fractional Orbital Bombardment System is much more capable of engaging targets on Earth with nuclear or conventional warheads, Rods from God bridge that range of weapon effects by kinetic kill - striking targets with telephone pole-sized tungsten rods from orbit, while satellites would accomplish every other conceivable purpose of a lunar military base (except for defending territory on the Moon). You don't have to spend propellant lifting a missile off the surface of the Moon to hit an object on Earth - just drop a warhead in a re-entry vehicle on your target directly from orbit. loupgarous (talk) 03:13, 1 January 2018 (UTC)[reply]

"species-preserving captivity"[edit]

Some accounts of the death in January of Colo (gorilla) say she was the first gorilla born in "species-preserving captivity". Does that qualifier mean anything? —Tamfang (talk) 09:19, 24 December 2017 (UTC)[reply]

That article says first gorilla to be born in captivity anywhere in the world, so probably not. I mean sure, in theory there's a difference between "intending" to raise gorillas with the purpose of killing them all off later and not doing so, but usually a farmer doesn't plan to kill his cattle. But it does sound nicer than saying you're raising it in captivity to keep zookeepers employed. ;) Wnt (talk) 10:13, 24 December 2017 (UTC)[reply]
To me, it means that the species is threatened by extinction in its natural habitat, so some are being held in captivity in order to preserve the species. I don't know whether they are in danger, I'm only telling you my interpretation. Akld guy (talk) 19:22, 24 December 2017 (UTC)[reply]
It might help if you linked to the article in question; our article (as Wnt says) states she was the first gorilla born in captivity period. So, if your question was whether the qualifier meant anything with regards to Colo herself, the answer would seem to be "no" (again, as mentioned above). However, if your question is more about species-preserving captivity in general, then yes, there is a distinction. We have a bit about it at zoo and more at ex situ conservation and captive breeding. I guess the short version would be that the qualifier means that the zoo or particular specimen in question was meant specifically to help boost the population of an endangered species, as opposed to zoos whose purposes are more in line with research or public entertainment. Matt Deres (talk) 04:12, 27 December 2017 (UTC)[reply]