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I Where on the Moon should the first Moonbase be?

  1. Mar 20, 2017 #1


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    Should it be on the farside to get radio silence for radio telescopes and explore there, or should it be at the pole for the ice, or in a cave?
  2. jcsd
  3. Mar 20, 2017 #2
    On balance I would say that close proximity to a known source of water would be the priority if we are talking about a permanently manned base.
    That not only directly solves a primary needs for a habitat, it also is a source of Oxygen, while Hydrogen is a storeable energy source.
  4. Mar 20, 2017 #3
    Jeff Bezos of Blue Origin thinks the rim of the Shackleton Crater at the south pole is a good spot. Ice is expected in the shadows of the rim and the rim has almost perpetual sun light for solar cells.
  5. Mar 23, 2017 #4
    To Moon colonists living on the Lunar south pole, would the Earth appear to be upside down (for the most part) on the horizon?
  6. Mar 23, 2017 #5
    The Earth would certainly be close to the horizon most of the time.
    I'm not sure of the alignment of the Moon's rotation axis compared with Earth's axis, but I'm pretty sure they don't align exactly.
    So the Earth might even appear sideways in relation to the Moon horizon.
  7. Mar 23, 2017 #6
    Wouldn't that depend on the observer's latitude on the Moon? If you're at the equator of the Moon and see the Earth on the horizon, I would think the Earth would be sideways, with other factors like the Earth's tilt and the Moon's tilt affecting precisely how sideways.
  8. Mar 26, 2017 #7

    Fervent Freyja

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    A place where the base is statistically less likely to be bombarded by large meteors? If it's really in random locations, then maybe a location recently hit.
  9. Mar 27, 2017 #8


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    Why recently hit? That doesn't make it less likely to be hit again.
    It might make it easier to investigate the debris.
    Perhaps high latitudes or the poles are less likely to be hit, since most objects in the solar system orbit in rougly the same plane.
  10. Mar 27, 2017 #9


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    Isn't the north pole also in almost perpetual sunlight?
    No matter.
    But I agree: with no clouds, and no night, the poles are ideal locations for solar.

    Secondary prime location candidates might be the lava tubes.

    Marius Hills
    Marius Hills "Hole"
    The hole, first discovered by the Japanese SELenological and ENgineering Explorer (SELENE) and then later imaged by the Lunar Reconnaissance Orbiter has been the subject of much research and speculation. There is a possibility that this feature could be a skylight in an underground lava tube. The depth of this hole is estimated to be between 80 and 88 m (262 and 289 ft) and its width is estimated to be several hundreds of meters.

    This tube could provide radiation shielding for a future underground lunar colony. However, it is unclear whether the tube is open or accessible. Two other lunar sites have been found by remote sensing, including on the far side's Mare Ingenii. An even larger, intact but buried lava tube estimated to be 1.7 km in length and 120m wide was detected by the Chandrayaan-1 orbiter.​

    Why spend a boat load of money to shield Selenites* when you can just give them a ladder.

    Also, according to a doodle by James Tuttle Keane at the 2017 LPSC, there's a hotel already waiting for guests in one of them.


    *Selenite, a fictional native inhabitant of the Moon; see Selene and The First Men in the Moon
  11. Mar 27, 2017 #10
    The first one on the ground will probably be located near lots of raw materials right near the surface. Automation will likely construct the base for us before anyone gets there.

    Is lunar orbit a possibility for the first one, or do we have to be underground to deal with the radiation?
  12. Mar 27, 2017 #11


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    I interpreted the OP's question as; "Where should the first 'human' moon base be?"

    But as I said earlier; "I agree". This time with your "Automation will likely construct the base for us before anyone gets there" statement.

    Sending a boatload of miniature 3-D printer bots to get things ready for us is the best plan of action, IMHO.

    And that location will be at one of the poles, as humans being water based, seem to have a serious addiction.
  13. Mar 27, 2017 #12
    What is has not been discussed very much is the hazards of meteoroids. With no atmosphere to burn them up all meteoroids will strike the surface. At speeds of 10's of thousands of mph they will carry quite a punch even tiny ones. The ISS has only been hit only a couple of times and by really small meteors so the strike frequency may be very2 small . However there are currently programs to determine strike rates on the moon at least those that you can see by their flash on impact. One of Jeff Bezos projects when he lands his robots on the moon is to locate the lunar rover. It will give some needed info on impact rate given that it has been there for over fifty years. None the less any colony on the moon will have to take meteoroids more seriously than down here on earth particularly the bigger ones for like in horse shoes close will count.
  14. Mar 27, 2017 #13
    I'm fairly certain that anything that'll stop a cosmic ray would stop a small meteoroid. Remember, any human base would have to be either underground, or covered in very thick shielding. I would think that either would be sufficient to block sand grain sized projectiles.
  15. Mar 27, 2017 #14
    But how thick? A 1 gram size meteoroid traveling at 20,000 mph has and energy of about 40,000 Joules or I oz. traveling at 1633 m/sec. Ouch! A 400 kg. (diameter about 0.5m) meteoroid was observed to produce a crater 40 m in diameter with an estimated depth of 4 - 6 m depth and that does not consider the shock wave it produces.

    The earth gets about 500 impacts a year of meteorites of 1m or less size, most of no consequence being destroyed in the atmosphere. The moon 1/4 the size should be expected to see 30 impacts per year. A 1 m diameter stone meteoroid (about 1400 Kg) traveling at 48,000 Kph has about 125.6 GJ of energy or equivalent to about 30 Tonnes of TNT.
  16. Mar 27, 2017 #15
    Plato Crater. Earth is visible at all times, no need for a relay satellite, vast room for expansion.
  17. Mar 28, 2017 #16
    I think a 1 gram object revealing at 20k would probably need less than six inches of dirt to stop. Dirt is pretty tough. If we were ten feet underground, I don't even think an impact like that would knock dust loose.

    I'm not sure what would stop a 1m impacted. I think we'd probably just accept the odds that it won't be likely and not care. Still, the deeper you dig, the less it matters. 30 tonnes of TNT is nothing, humans have experience building facility designed for nuclear weapons with orders of magnitude more power.
  18. Mar 29, 2017 #17


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    Lava tubes look like an ideal place for human habitation. They would offer protection from both radiation and meteoroids.
  19. Mar 29, 2017 #18


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    If it's in orbit, it would need a lot of shielding. Maybe use Moon rock? That needs rockets to lift it off the Moon, and rocket fuel that could come from Lunar Ice. https://nssdc.gsfc.nasa.gov/planetary/ice/ice_moon.html
  20. Mar 29, 2017 #19


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    Is it easier to have robots dig and transport the ice to a base in a cave, or have them pile lots of dirt on the roof of a base at the poles?

    OR a third option: a place with very porous ground that's easy to dig into: https://phys.org/news/2017-03-young-looking-lunar-volcano-true-age.html
  21. Mar 30, 2017 #20
    The cheapest way to launch space station shielding mass into orbit is with a magnetic catapult. Lunar iron for the shell, fill with rock. Only a tiny bit of fuel needed to raise the perilune if the package isn't intercepted on the first pass. High-G cargo like rock, LOX, refined metals, etc. can use quite a short catapult, more delicate stuff including humans will need a 20 or 30 km launcher to keep Gs survivable. Not an early infrastructure, but economically compelling as the enterprise grows.
    Best location is likely near the equator, but a polar launcher might be justifiable.
  22. Mar 30, 2017 #21


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    I don't know any robots, so I don't know what would be easiest for them.
    But I'm sticking with my first choice, in response to your original question: One of the poles
    I would just tell them what to do, and deal with their complaints as they arise.
    I don't know anything about moon geography, so I can't even make a guess.

    This is an excellent idea.
    Though, I don't know why you say the best location is likely near the equator, as the moon barely rotates.

    Interesting that you came up with "20 or 30 km launcher", as I came up with 22.9 km.
    Did you also use the world's highest G-Force on a Roller Coaster number?: 6.3 g's

    Other numbers I came up with for a moon based maglev orbital launder, based on that number, and the surface orbital speed: 1.68 km/sec:
    zero to 1.68 km/sec: 27.2 seconds
    energy required per kilogram: 1.41 million joules
    power required per kilogram: 51.9 kilowatts​

    note: These numbers are for a surface orbit. I'm not really sure where the best lunar orbit is, so I didn't bother calculating the extra energy to get there.

    opinion: Regardless of where they put your launcher, I think the final trajectory should point towards earth. But this is just a naive notion, based on mere ponderings, and should be therefore taken with a grain of salt.
  23. Mar 30, 2017 #22
    Keep in mind that, due to variations in the Moon's motions, neither pole get continuous sunlight. I once thought just find the highest polar point and have solar on trackers but it was pointed on a forum much like this that the moon wobbles on it's axis, more than I had thought. Nutation I think? Having multiple sites for continuous solar power with the shortest transmission lines would have to be near the poles but for a moon-base I doubt that such extensive construction would be feasible; it is more likely to be a modular construction, built on Earth and provided with all it needs including (nuclear) power plant, water, air and food. There might be experiments around the feasibility of resource extraction for local use or on-site food production but it's unlikely to relied upon.

    I remain very doubtful we will see it - difficult, expensive and lacking tangible benefits to those who pay for it.
  24. Mar 30, 2017 #23
    We have not yet even constructed a permanently inhabited colony under the Seas of Earth,
    where there are tons of useful resources and an environment that is not too risky.
    ( I don't think submarines count)
  25. Mar 30, 2017 #24
    I worked out a few solutions between 8 Gs and 4 Gs (Mercury/Atlas and Gemini flights peaked between 7 and 8 Gs on launch, but that's fairly punishing). 4 Gs (Apollo/Space Shuttle/Soyuz levels) needs a 33 km track.
    There's little or nothing to be gained from equatorial motion - I'm no orbital mechanic but on pondering this I now don't see much need for equatorial orbits. My main concern was matching with stuff placed in equatorial Lunar orbit from the Earth, but it seems almost as easy to put things in Lunar polar orbit from here anyway.
    With enough delta V, a direct trip, Luna to Earth (or even to Mars), would be possible.
  26. Mar 30, 2017 #25
    Would it be a lot cheaper to run a particle accelerator on the moon with no air for the vacuum ring and the cold to keep the supper magnets cool anuf to work right as well as less g force to overcome with the particles????
    Could we see this as motivation good for getting a base up their ??
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