Lifeboat Foundation: Safeguarding Humanity
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Category: space – Page 1055

It’s been a while since anyone contributed a post on space exploration here on the Lifeboat blogs, so I thought I’d contribute a few thoughts on the subject of potential hazards to interstellar travel in the future — if indeed humanity ever attempts to explore that far in space.

It is only recently that the Voyager probes provided us with some idea of the nature of the boundary of our solar system with what is commonly referred to as the local fluff, The Local Interstellar Cloud, through which we have been travelling for the past 100,000 years or so, and which we will continue to travel through for another 10,000 or 20,000 years yet. The cloud has a temperate of about 6000°C — albeit very tenuous.

We are protected by the effects of the local fluff by the solar wind and the sun’s magnetic field, the front between the two just beyond the termination shock where the solar wind slows to subsonic velocities. Here, in the heliosheath, the solar wind becomes turbulent by its interaction with the interstellar medium, and keeping the interstellar medium at bay from the inners of the solar system, the region currently under study by the Voyager 1 and Voyager 2 space probes. It has been hypothesised that there may be a hydrogen wall further out between the bow shock and the heliopause composed of ISM interacting with the edge of the heliosphere, another obstacle to consider with interstellar travel.

The short end of the stick is that what many consider ‘open space’ to traverse once we get beyond the Kuiper belt may in fact be many more mission-threatening obstacles to traverse to reach beyond our solar system. Opinions welcome. I am not an expert on this.

On a casual read of the appraised work of Duncan R. Lorimer on Binary and Millisecond Pulsars (2005) last week, I noted the reference to the lack of pulsars with P < 1.5 ms. It cites a mere suggestion that this is due to gravitational wave emission from R-mode instabilities, but one has not offered a solid reason for such absence from our Universe. As the surface magnetic field strength of such would be lower (B ∝ (P ˙P )^(1÷2)) than other pulsars, one could equally suggest that the lack of sub millisecond pulsars is due to their weaker magnetic fields allowing CR impacts resulting in stable MBH capture… Therefore if one could interpret that the 108 G field strength adopted by G&M is an approximate cut-off point where MBH are likely to be captured by neutron stars, then one would perhaps have some phenomenological evidence that MBH capture results in the destruction of neutron stars into black holes. One should note that more typical values of observed neutron stars calculate a 1012 G field, so that is a 104 difference from the borderline-existence cases used in the G&M analysis (and so much less likely to capture). That is not to say that MBH would equate to a certain danger for capture in a planet such as Earth where the density of matter is much lower — and accretion rates much more likely to be lower than radiation rates — an understanding that is backed up by the ‘safety assurance’ in observational evidence of white dwarf longevity. However, it does take us back to question — regardless of the frequently mentioned theorem here on Lifeboat that states Hawking Radiation should be impossible — Hawking Radiation as an unobserved theoretical phenomenon may not be anywhere near as effective as derived in theoretical analysis regardless of this. This oft mentioned concern of ‘what if Hawking is wrong’ of course is endorsed by a detailed G&M analysis which set about proving safety in the scenario that Hawking Radiation was ineffective at evaporating such phenomenon. Though doubts about the neutron star safety assurance immediately makes one question how reliable are the safety assurances of white dwarf longevity – and my belief has been that the white dwarf safety assurance seems highly rational (as derived in a few short pages in the G&M paper and not particularly challenged except for the hypothesis that they may have over-estimated TeV-scale MBH size which could reduce their likelihood of capture). It is quite difficult to imagine a body as dense as a white dwarf not capturing any such hypothetical stable MBH over their lifetime from CR exposure – which validates the G&M position that accretion rates therein must be vastly outweighed by radiation rates, so the even lower accretion rates on a planet such as Earth would be even less of a concern. However, given the gravity of the analysis, those various assumptions on which it is based perhaps deserves greater scrutiny, underscored by a concern made recently that 20% of the mass/energy in current LHC collisions are unaccounted for. Pulsars are often considered one of the most accurate references in the Universe due to their regularity and predictability. How ironic if those pulsars which are absent from the Universe also provided a significant measurement. Binary and Millisecond Pulsars, D.R. Lorimer: http://arxiv.org/pdf/astro-ph/0511258v1.pdf

Russia’s hastily convened international conference in St. Petersburg next month is being billed as a last-ditch effort at superpower cooperation in defense of Earth against dangers from space.

But it cannot be overlooked that this conference comes in response to the highly controversial NATO anti-ballistic missile deployments in Eastern Europe. These seriously destabilizing, nuclear defenses are pretexted as a defense against a non-nuclear Iran. In reality, the western moves of anti-missile systems into Poland and Romania create a de facto nuclear first-strike capability for NATO, and they vacate a series of Anti-Ballistic Missile Treaties with the Russians that go back forty years.

Deeply distrustful of these new US and NATO nuclear first-strike capabilities, the Russians announced they will not attend NATO’s planned deterrence summit in Chicago this month. Instead, they are testing Western intentions with a proposal for cooperative project for near-space mapping, surveillance, and defense against Earth-crossing asteroids and other dangerous space objects.

The Russians have invited NATO members as well as forward-thinking space powers to a conference in June in Petrograd. The agenda: Planetary defense against incursions by objects from space. It would be a way of making cooperative plowshares from the space technologies of hair-trigger nuclear terror (2 minutes warning, or less, in the case of the Eastern European ABMs).

It’s an offer the US and other space powers should accept.

High energy experiments like the LHC at the nuclear research centre CERN are extreme energy consumers (needing the power of a nuclear plant). Their construction is extremely costly (presently 7 Billion Euros) and practical benefits are not in sight. The experiments eventually pose existential risks and these risks have not been properly investigated.

It is not the first time that CERN announces record energies and news around April 1 – apparently hoping that some critique and concerns about the risks could be misinterpreted as an April joke. Additionally CERN regularly starts up the LHC at Easter celebrations and just before week ends, when news offices are empty and people prefer to have peaceful days with their friends and families.

CERN has just announced new records in collision energies at the LHC. And instead of conducting a neutral risk assessment, the nuclear research centre plans costly upgrades of its Big Bang machine. Facing an LHC upgrade in 2013 for up to CHF 1 Billion and the perspective of a Mega-LHC in 2022: How long will it take until risk researchers are finally integrated in a neutral safety assessment?

There are countless evidences for the necessity of an external and multidisciplinary safety assessment of the LHC. According to a pre-study in risk research, CERN fits less than a fifth of the criteria for a modern risk assessment (see the press release below). It is not acceptable that the clueless member states point at the operator CERN itself, while this regards its self-set security measures as sufficient, in spite of critique from risk researchers, continuous debates and the publication of further papers pointing at concrete dangers and even existential risks (black holes, strangelets) eventually arising from the experiments sooner or later. Presently science has to admit that the risk is disputed and basically unknown.

It will not be possible to keep up this ostrich policy much longer. Especially facing the planned upgrades of the LHC, CERN will be confronted with increasing critique from scientific and civil side that the most powerful particle collider has yet not been challenged in a neutral and multidisciplinary safety assessment. CERN has yet not answered to pragmatic proposals for such a process that also should constructively involve critics and CERN. Also further legal steps from different sides are possible.

The member states that are financing the CERN budget, the UN or private funds are addressed to provide resources to finally initiate a neutral and multidisciplinary risk assessment.

German version of this article published in Oekonews: http://www.oekonews.at/index.php?mdoc_id=1069458

Related LHC-Critique press release and open letter to CERN:

https://lifeboat.com/blog/2012/02/lhc-critique-press-release…hc-upgrade

Typical physicist’s April joke on stable black holes at the LHC (April 1 2012, German): http://www.scienceblogs.de/hier-wohnen-drachen/2012/04/stabi…rzeugt.php

Latest publications of studies demonstrating risks arising from the LHC experiment:

Prof Otto E. Rössler: http://www.academicjournals.org/AJMCSR/PDF/pdf2012/Feb/9%20Feb/Rossler.pdf

Thomas Kerwick B.Tech. M.Eng. Ph.D.: http://www.vixra.org/abs/1203.0055

Brief summary of the basic problem by LHC-Kritik (still valid since Sep. 2008): http://lhc-concern.info/wp-content/uploads/2008/12/lhc-kriti…ry-908.pdf

Detailed summary of the scientific LHC risk discussion by LHC-Kritik and ConCERNed International: http://lhc-concern.info/wp-content/uploads/2010/03/critical-…ed-int.pdf

We wish you happy Easter and hope for your support of our pragmatic proposals to urgently increase safety in these new fields of nuclear physics.

LHC Critique / LHC Kritik — Network for Safety at nuclear and sub-nuclear high energy Experiments.

www.LHC-concern.info

[email protected]

Tel.: +43 650 629 627 5

New Facebook group: http://www.facebook.com/groups/LHC.Critique/

I have on occasion used the term ‘the neutron star paradox’ amongst LHC safety critics to denote the existence of neutron stars, as micro black hole capture should invalidate their existence if micro black holes were stable, according to official safety reports. The oft used counter-argument being that of superfluidity, which I personally dismiss as bunkum (zero viscosity cannot slip and slide your way out from the dark side of an event horizon).

It would be more appropriate to consider the magnetic field of the neutron star such that cosmic rays are always deflected by the Lorentz force from such stars, or perhaps some solar wind type effect may do similar (though this has at least partly been argued against in safety assurance already). The alternative (and infinitely more plausible) explanation of course is that micro black holes (TeV scale, at least) do not exist, though dozens of papers on arXiv and other journals argue otherwise (and CERN scientists willfully anticipate the creation of approx. 10,000 of these over the course of LHC experiemnts). The slightly less plausible explanation is that Hawking Radiation Theory is actually effective, with the only other explanation being that MBH accretion models are flawed. Otherwise we would not have stable neutron stars in the Universe… they would all be black holes by now.

I thought I’d kick off a thread of discussion here — if anyone has the appetite to participate — on discussion of ‘The Neutron Star Paradox’, as you will see from my previous post on the flux of (hypothetical) stable micro black holes, this is quite central to LHC safety assurance.

- CERN’s annual meeting to fix LHC schedules in Chamonix: Increasing energies. No external and multi-disciplinary risk assessment so far. Future plans targeting at costly LHC upgrade in 2013 and Mega-LHC in 2022.

- COMMUNICATION to CERN – For a neutral and multi-disciplinary risk assessment before any LHC upgrade

According to CERN’s Chamonix workshop (Feb. 6–10 2012) and a press release from today: In 2012 the collision energies of the world’s biggest particle collider LHC should be increased from 3.5 to 4 TeV per beam and the luminosity is planned to be increased by a factor of 3. This means much more particle collisions at higher energies.

CERN plans to shut down the LHC in 2013 for about 20 months to do a very costly upgrade (for CHF 1 Billion?) to run the LHC at double the present energies (7 TeV per beam) afterwards.

Future plans: A High-Luminosity LHC (HL-LHC) is planned, “tentatively scheduled to start operating around 2022” — with a beam energy increased from 7 to 16.5 TeV(!):
http://cdsweb.cern.ch/journal/CERNBulletin/2012/06/News%20Articles/1423292?ln=en

One might really ask where this should lead to – sooner or later – without the risks being properly investigated. Many critics from different fields are severely alarmed.

For comparison: The AMS 2 experiment for directly measuring cosmic rays in the atmosphere operates on a scale around 1.5 TeV. Very high energetic cosmic rays have only been measured indirectly (their impulse). Sort, velocity, mass and origin of these particles are unknown. In any way, the number of collisions under the extreme and unprecedented artificial conditions at the LHC is of astronomical magnitudes higher than anywhere else in the nearer cosmos.

There were many talks on machine safety at the Chamonix meeting. The safety of humans and environment obviously were not an official topic. That’s why critics turned to CERN in an open letter:

———————————————————–
Communication on LHC Safety directed to CERN

For a neutral and multidisciplinary risk assessment to be done before any LHC upgrade

—————————-
Communiqué to CERN
—————————-

Dear management and scientists at CERN,

Astronomer and Leonardo-publisher Roger Malina recently emphasized that the main problem in research is that “curiosity is not neutral”. And he concluded: “There are certain problems where we cannot cloister the scientific activity in the scientific world, and I think we really need to break the model. I wish CERN, when they had been discussing the risks, had done that in an open societal context, and not just within the CERN context.”

Video of Roger Malina’s presentation at Ars Electronica, following prominent philosopher and leading constructivist Humberto Maturana’s remarkable lecture on science and “certainy”: https://www.youtube.com/watch?v=DOZS2qJrVkU

In the eyes of many critics a number of questions related to LHC safety are not ruled out and some of them have concrete and severe concerns. Also the comparability of the cosmic ray argument is challenged.

Australian risk researcher and ethicist Mark Leggett concludes in a paper that CERN meets less than a fifth of the criteria of a modern risk assessment:
http://lhc-concern.info/wp-content/uploads/2009/09/leggett_r…_1__09.pdf

Without getting into details of the LHC safety discussion – this article in the well-recognized Physics arXiv Blog (MIT’s Technology Review) states: “Black Holes, Safety, and the LHC Upgrade — If the LHC is to be upgraded, safety should be a central part of the plans.”

Similar to pragmatic critics, the author claims in his closing remarks: “What’s needed, of course, is for the safety of the LHC to be investigated by an independent team of scientists with a strong background in risk analysis but with no professional or financial links to CERN.”
http://www.technologyreview.com/blog/arxiv/27319/

The renowned Institute for Technology Assessment and Systems Analysis (ITAS) in Karlsruhe and other risk researchers have already signalized interest in cooperation. We think, in such a process, naturally also CERN and critics should be constructively involved.

Please act in favour of such a neutral and multi-disciplinary assessment, maybe already following the present Chamonix meeting. Even if you feel sure that there are no reasons for any concerns, this must be in your interest, while also being of scientific and public concern.

In the name of many others:
[…]
————————–
LHC-Kritik / LHC-Critique
www.LHC-concern.info

Direct link to this Communication to CERN:
http://lhc-concern.info/?page_id=139
Also published in “oekonews”: http://www.oekonews.at/index.php?mdoc_id=1067776

CERN press release from Feb 13 2012:
http://press.web.cern.ch/press/PressReleases/Releases2012/PR01.12E.html

“Badly designed to understand the Universe — CERN’s LHC in critical Reflection by great Philosopher H. Maturana and Astrophysicist R. Malina”:
https://lifeboat.com/blog/2012/02/badly-designed-to-understa…t-r-malina

“LHC-Kritik/LHC-Critique – Network for Safety at experimental sub-nuclear Reactors”, is a platform articulating the risks related to particle colliders and experimental high energy physics. LHC-Critique has conducted a number of detailed papers demonstrating the insufficiency of the present safety measures under well understandable perspectives and has still got a law suit pending at the European Court of Human Rights.

More info at LHC-Kritik / LHC-Critique:
www.LHC-concern.info
[email protected]
+43 650 629 627 5

As we all know, Venus’s atmosphere & temperature makes it too hostile for colonization: 450°C temperatures and an average surface pressure almost 100 times that of Earth. Both problems are due to the size of its atmosphere — massive — and 95% of which is CO2.

The general consensus is that Venus was more like that of the Earth several billion years ago, with liquid water on the surface, but a runaway greenhouse effect may have been caused by the evaporation of the surface water and subsequent rise of greenhouse gases.

It poses not just a harsh warning of the prospects of global warming on Earth, but also a case study for how to counter such effects — reversing the runaway greenhouse effect.

I have wondered if anyone has given serious thought to chemical processes which could be set in motion on Venus to extract the carbon dioxide from the atmosphere. The most common gas in the Universe is of course hydrogen, and if sufficient quantities could be introduced to the Venusian atmosphere, with the appropriate catalysts, could the carbon dioxide in the atmosphere be eventually reversed back into solid carbon compounds, water vapor and oxygen? The effect of this would of course not only bring down the temperature, but return the surface pressure, with 95% of its atmosphere removed, to one more similar to that of Earth. Perhaps in adding other aerosols the temperatures could be reduced further and avoid a re-runaway effect.

I’d like to hear others thoughts on this. It would be a long term project — but would perhaps make our closest planet our most habitable one in the future — one we could turn into a habitat that would be very accessible, with ample oxygen, water and mineral resources… The study of such a process would also greatly benefit Earth in the event that theorized runaway greenhouse effects start to occur on our own planet, the strategies learned could save it. Other issues to address regarding Venus: lack of magnetic field and its slow rotation would have to be considered, though hardly off-putting, and 150ppm sulfur dioxide in the atmosphere would need to be cleansed — surely not insurmountable.

There has been a lot of discussion about a lunar colony or at least a base as a precursor to sending humans to Mars. The advantages cited are its proximity to Earth, the use of telerobotics for construction, and the fact that we’ve been there before. My position is that it would be far easier to establish a self sufficient colony on Mars with existing technology.

One thing everyone agrees on is that local resources will have to be used. We now know that There has been a lot of geological and hydrological activity on Mars that has segregated and concentrated useful ore bodies that can be exploited with current extractive technology. One type of mineral of interest is the occurrence of iron and magnesium carbonate formations on the surface. Magnesium carbonate is easily converted by heating to magnesium oxide, the primary component of a type of cement that I am researching as a construction material for Mars. The widespread occurrence of sulfate salts also gives reason to believe that metal sulfide ore bodies are also available there. This type of ore can easily be refined with simple electrolytic equipment. The same metal refining on the Moon would require grinding and processing basalt with a lot of heavy equipment.

I would argue that Mars also has a more friendly environment. First, it has higher gravity than the moon, at 38% of Earth’s gravity. This may prove to be significant in minimizing the health effects of reduced gravity. The higher gravity would also aid in many industrial processes such as ore separation and concrete consolidation. Mars also has an atmosphere, however thin. While 4 to 8 millibars may not sound like much, it is enough to burn up a lot of micrometeorites before they reach the surface, reducing the danger of micrometeorite damage. It may also help reduce the danger of galactic cosmic rays, but that will need to be tested. One thing that is certain from my own research is that the thin atmosphere is enough to allow magnesium oxychloride cement to cure before a significant amount of water has evaporated from it, and prevent boiling during the curing process. On the airless Moon, this type of cement would boil violently and the water would evaporate before it would cure. The total lack of atmosphere on the Moon would preclude the use of any cement that depends on water for curing.

Dust will be the biggest challenge to machinery in either place, and I argue that it is much less of a challenge on Mars. We have already studied lunar dust, and it is composed of fractured particles that retain sharp edges and points, with no mechanisms for smoothing the surfaces such as wind or water movement. This makes Moon dust very abrasive to machinery (and air seals) and very irritating to human tissues on contact. Mars has annual wind storms that blow dust around the planet, and has had flowing water recently in it’s history. This would serve to smooth out Martian dust particles to something more closely resembling the kind of material found on Earth, which we can more easily deal with. As further evidence, we have had rovers survive multiple dust storms and keep operating. I would say this is as much a testament to the Martian environment as it is to NASA engineers. Additionally, the dust has been found to be largely magnetic, meaning that magnetic filtration could be used to keep it out of habitable spaces.

Some would argue that solar power is more abundant on the Moon, but the problem there is that it intermittent. 14 days on, then 14 days off. Power either has to be stored for two weeks at a time, or produced from other sources. On Mars, you just need to get through a single night. The dust storms can cause problems of course, but that is at most a month out of every 22.

Finally, there is the question of water. On the Moon, water ice is probably at the bottom of some deep craters near the poles. It can probably be mined beneath the surface, we are just not sure how far down we need to go. On Mars, snow has been observed made up of water ice, and water ice has been seen just beneath the surface in rover tracks. It appears to be everywhere, just below the surface.

The Moon may be closer as the bird flies, but in terms of energy to get there, Mars is not much further. The biggest challenge will be getting humans there alive, but once that is done the learning curve once we get there is much shorter. Instead of developing new and untested industrial processes to exploit lunar resources, we can use proven technology to exploit Martian resources with much less effort. The prize is there for the taking, and there is no point in stopping on the way to build a temple to Luna.

Recently, Newt Gingrich made a speech indicating that, if elected, he would want 10% of NASA’s budget ($1.7 billion per year) set aside to fund large prizes incentivizing private industry to develop a permanent lunar base, a new propulsion method, and eventually establishing a martian base.

THE FINANCIAL FEASIBILITY OF A LUNAR BASE
Commentators generally made fun of his speech with the most common phrase used being “grandiose”. Perhaps. But in 1996 the Human Lunar Return study estimated $2.5 billion from NASA to send and return a human crew to the Moon. That was before SpaceX was able to demonstrate significant reductions in launch costs. One government study indicated 1/3 of the cost compared to traditional acquisition methods. Two of SpaceX’s Falcon Heavies will be able to launch nearly as much payload as the Saturn V while doing so at 1/15th the cost of the same mass delivered by the Shuttle.

So, we may be at the place where a manned lunar base is within reach even if we were to direct only 10% of NASA’s budget to achieve it.

I’m not talking about going to Mars with the need for shielding but rather to make fast dashes to the Moon and have our astronauts live under Moon dirt (regolith) shielding while exploiting lunar ice for air, water, and hence food.

IS A SMALL COLONY WITHIN REACH?
But the point of this post is this. If a small lunar base is within our reach, how much more would it take to achieve something that most of us realize would be the single most important step in ensuring the survival of the human species should a truly existential event strike Planet Earth. So I’m describing a small, self-sufficient colony. I would say that the difference between a base and a self-sufficient colony is fairly small. Small enough to make it worth our while to attempt to achieve.

THE MOST ESSENTIAL REQUIREMENTS
So, what are the requirements for a self-sufficient colony? The most critical would be air, water, and food. But understand, oxygen and water can be produced from the 600 million metric meters of water ice estimated to exist at the north lunar pole. So there’s no shortage. And with recycling, the amount of daily required input could be pretty small — small enough to easily be within a day’s task for mining. But food also requires fertilizer. Fortunately for us, the LCROSS results showed that there is also methane and ammonia in the ice and the regolith contains other minerals such as phosphorus and potassium. So, the most critical components for a colony would already be present with a manned base at a lunar pole.

HABITATS
Besides this, the colony would also need protection from the vacuum and cosmic radiation — i.e. a sealed habitat. This should not be too difficult. For a base, options include inflatable habitats and using fuel tanks as durable, sealable compartments. Radiation protection is as simple as piling regolith over the structures or even digging trenches or caves into the sides of hills or craters. That’s fine for a base. But a self-sufficient colony requires that future colonists be able to construct their own habitats. This could be achieved in the intermediate term by simply caving out habitats, supporting them, and then inflating a liner. Many such liners could be delivered in a single 5,000 kg payload. In the long term, such liners could be produced as plastics from volatiles resulting from the production of water from lunar ice. Broken liners could be patched or even melted to produce new liners. Alternately, metals can be fairly easily produced from the regolith. Run a permanent magnet through the soil, extract iron, melt it using solar concentrating mirrors and then process the molten metal to sheets, wires, cast forms, etc. Glass could be made the same way along with fiberglass. Natural lighting could supplement electrical power by using aluminum mirrors and glass. Supplemental heat could be provided in a similar manner along with locally derived insulation.

ELECTRICITY
Thin film solar panels can provide > 1,000 W/kg. So a 5,000 kg payload could provide a very large amount of onging power (if my math is correct, enough for perhaps 500 colonists). Excessive solar panels could be stored under ground and then used as needed thereby giving the colony decades of power. Eventually, a self-sustaining colony would need to produce its own power from silicon in the regolith. Storage of energy during the lunar night could be accomplished through the use of electrolysis of water to oxygen and hydrogen. These could then be recombined in a fuel cell to produce electricity and heat. Alternately, the colonists could simply travel every two weeks to the other side of the hill near the pole to another sunlit habitat.

CLOTHING
Again, to buy the colony time to be able to develop the ability to produce its own space suits, many years’ worth of thin airproof liners to space suits could be delivered in a single 5,000 kg payload. Again, a self-sustaining colony would need to eventually produce their own. Between the use of fiberglass, metals, and locally produced plastic or silicon sealants, eventually the colony could produce their own. Of course plants could be grown to provide fibers for clothing.

EQUIPMENT
To avoid day-long exposure to cosmic radiation while mining surface ice, mining could either be conducted underground or telerobotically. But regolith is very gritty and can wear out teleoperated mining equipment. But if a colony is able to produce its own metals and had machining equipment which could be used to produce more machining equipment, then the colony could stay ahead of equipment wearing out.

High-tech equipment (computer chips, cameras, and radio equipment) is certainly useful but I believe that there are ways around needing them. Still, in the interim, a single 5,000 kg payload delivery could provide centuries worth of computer chips, camera chips, and critical radio equipment components. For example, the Voyager craft have been exposed to 30+ years of 360 degree space radiation yet still work fine. So, an apple box worth of computer chips could last centuries. Eventually the colony would need to produce its own high-tech equipment. Perhaps they could use 1940’s technology such as vacuum tubes.

GRAVITY & PREGNANCY
The Moon’s 1/6 gravity is probably not enough to prevent bone and muscle loss. Experiments on the international space station (ISS) show that an exercise program can do much to prevent bone loss. A recent study indicates that Fosamax prevents bone loss in astronauts. A 5,000 kg payload could give 83 million doses of Fosamax. Stored in a permanently shadowed area, it could provide for a very large number of future colonists. But also, a basic centrifuge or even a tether ball-like contraption could provide artificial gravity for colonists for part of the day. Trenches dug along its path could provide partial protection from cosmic rays. Alternately, space forums have discussed completely underground centrifuges using various ingenious approaches.

Of particular concern is how fetal children would develop given limited gravity. Studies of animals on the ISS indicates that this is a real concern. We don’t know enough about this issue. Perhaps pregnant women would need to spend significant amounts of time in a centrifuge perhaps in all trimesters.

ADDITIONAL REQUIREMENTS
I have started with the most essential requirements and have worked down. I propose that there are technologic solutions for each of the requirements but perhaps I have been unrealistic in one or more areas or perhaps have neglected to address an important requirement. Feel free to comment below.

GENETIC DIVERSITY
For a truly self-sustaining colony, for humans, the Minimum Viable Population (MVP) is in the realm 1,000. I personally suspect that it is actually less than that but a solution here could be for a single payload delivery of frozen embryos for surrogate parenting to be frozen long-term in permanently shadowed areas. Although this may strike some as being unethical, these would only be needed in the event of a truly existential event on Planet Earth.

PRESERVING THE BIOSPHERE
I envision the colony as not only securing the human species but a good representation of Earth’s entire biosphere. But discussing the details of that topic would extend this post much longer than it has already become. More on that later.

One way that astronomers and astrobiologists search for life in the galaxy is observation of rocky planets orbiting other stars. Such planets may contain an atmosphere, liquid water, and other ingredients that are required for biological life on Earth. Once a number of these potentially inhabited planets have been identified, the next logical step in exploration is to send remote exploratory probes to make direct observations of these planets. Present-day study of other planetary systems is so far limited to remote observation with telescopes, but future plans for exploration include the design and deployment of small robotic exploratory spacecraft toward other star systems.

If intelligent, technological extraterrestrial life exists in the galaxy, then it is conceivable that such a civilization might embark on a similar exploration strategy. Extraterrestrial intelligent (ETI) civilizations may choose to pursue astronomy and search for planets orbiting other star systems and may also choose to follow-up on some of these targets by deploying their own remote exploratory spacecraft. If nearby ETI have observed the Solar System and decided to pursue further exploration, then evidence of ETI technology may be present in the form of such exploratory probes. We refer to this ETI technology as “non-terrestrial artifacts”, in part to distinguish these plausible exploratory spacecraft from the flying saucers of science fiction.

In a recent paper titled “On the likelihood of non-terrestrial artifacts in the Solar System”, published in the journal Acta Astronautica (and available on arXiv.org as a preprint), Jacob Haqq-Misra and Ravi Kopparapu discuss the likelihood that human exploration of the Solar System would have uncovered any non-terrestrial artifacts. Exploratory probes destined for another star system are likely to be relatively small (less than ten meters in diameter), so any non-terrestrial artifacts present in the Solar System have probably remained undetected. The surface and atmosphere of Earth are probably the most comprehensively searched volumes in the Solar System and can probably be considered absent of non-terrestrial artifacts. Likewise, the surface of the moon and portions of Mars have been searched at a sufficient resolution to have uncovered any non-terrestrial artifacts that could have been present. However, the deep oceans of Earth and the subsurface of the Moon are largely unexplored territory, while regions such as the asteroid belt, the Kuiper belt, and stable orbits around other Solar System planets could also contain non-terrestrial artifacts that have so far escaped human observation. Because of this plenitude of nearby unexplored territory, it would be premature to conclude that the Solar System is absent of non-terrestrial artifacts.

Although the chances of finding non-terrestrial artifacts might be low, the discovery of ETI technology, even if broken and non-functioning, would provide evidence that ETI exist elsewhere in the galaxy and have a profound impact on humankind. This is not to suggest that the search for non-terrestrial technology should be given priority over other astronomical missions; however, as human exploration into the Solar System continues, we may as well keep our eyes open for ETI technology, just in case.