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41

The United States (along with Russia, China, Japan, India, and most other space-faring nations) did not sign (or in some cases, ratify) the Moon Treaty, and so companies that are registered in any of these countries are also not bound by it. So, that treaty is essentially pointless for anyone who actually has the ability to get to the moon in the first ...


19

With all the hype in the news this was surprisingly hard to research for specifically 2011 UW158. I never did find a source for the claim on the value, though the Slooh Community Observatory put the claim at "\$300 billion to as much as \$5.4 trillion dollars worth of precious metals and minerals". The answer basically seems to come down to: we've analyzed ...


16

This answer is outdated. The Dawn flyby in February 2015 added a lot of information which was not known at the writing of this answer. We don't actually know much about Ceres. All we know about it is from earth-based or earth-orbit-based observation. Until now it wasn't visited by a probe, but the Dawn spacecraft will do so in February 2015. This will ...


13

For a Hohmann transfer to Saturn, I get 15.7 km/s for both burns. The transfer time is also a simple formula. I obtain roughly 6 years. Compare to the lunar ice. It is roughly 2.8 km/s to get to, and the trip time would be a few days, even from Low Earth Orbit. As suggested by the other answer, you could compare to Earth's surface. If we're using some ...


13

Yes. Planetary Differentiation is the key here. When enough smaller asteroids smash together and form a big enough body, the heavy stuff sinks to the bottom (iron and other metals), middle layers tend to be formed of silicates (i.e. sand and rocks), and the lighter stuff floats on top (water, methane). (Mind you, the examples here are based on the ...


13

On Earth, before a mineral or petroleum resource is mined/extracted, the deposit is delineated and evaluated. Briefly, the process involves sending a some geologists and some drill rigs and their operators to a deposit and drilling holes through the deposit on a predetermined grid pattern. The drill cuttings or core (depending on the type of drill used) will ...


13

the Moon is actually pretty damn small The Moon is actually pretty damn enormous. The mass of the Moon is about $7.34 \times 10^{22}$ kilograms. As a point of comparison, all the copper ever mined on Earth comes to 700 million tons - that is, $7 \times 10^{11}$ kilograms, or $\frac 1 {100000000000}$ of the total mass of the moon. Removing that much mass won'...


12

As others have stated in their answers, there is no evidence, so far, that there is gold on Mars. We can't say there is or there isn't gold on Mars, we just haven't found any yet. We also don't know if gold were to exist, if it occurs in concentrated deposits, amenable to mining, or whether it's disseminated. Gold hasn't been the focus of the exploration of ...


10

If gravity was repulsive between the Earth and the asteroid, this could at least make sense in principle. In that case, getting close is like pushing on a spring, and with a carefully managed trajectory, you might be able to finish the trajectory on the surface, with zero gravity. But gravity isn't like a pushing spring, it's like a pulling spring. That ...


10

In terms of delta-v budget there could be large savings in transporting required materials from the Moon to LEO (∆V ~ 2.74 km/s) instead of Earth to LEO (∆V ~ 9.3 - 10 km/s) [1], assuming you can reduce excess orbit insertion velocity (~ 3.3 km/s from about 11 km/s reentry speed to 7.7 km/s for ISS) that builds up due to Earth's larger Hill sphere with ...


10

Sorry to spoil everyone’s excitement, but one claim, credited to Mining.com, that the kilometer-wide asteroid might contain “up to 90 million metric tons of platinum and other precious metals” is wrong and is orders of magnitude too high. Assuming the asteroid to be roughly spherical and 3280 feet (1 kilometer) across and being the more uncommon “nickel-...


10

Two big ifs here. IF we achieved viable commercial fusion power (other than the sun) and IF He3 was an indispensable part of this process. But for the sake of argument, let's say He3 is the fusion fuel of the future. I'll quote John Schilling's comment from Rand Simberg's Transterrestrial Musings blog. Helium-3 mining on the moon simply does not pass ...


10

That sounds like a terrible idea. The article says that: Lastly, Both planets contain high concentrations of methane. Like graphite, it too can actually transform into various forms of complex hydrocarbons given enough heat and pressure. Consider this: Pressure is high enough to make diamonds, so any mining equipment would need to sustain even ...


10

Given your constraints I can't see it being worthwhile, period, even if it were our own moon. Lets throw some numbers at it: Current cost to deliver a kilogram of payload to the moon: \$1.2 million. Price of a kilogram of gold: \$40k. In other words, for every kilogram you land on the target you need to bring back 30kg of gold just to pay your launch ...


10

NASA [1] indicates that helium-3 can be assessed indirectly by measuring the presence of titanium dioxide and soil characteristics ("maturity"), the correlation having been derived from the study of Apollo lunar rock samples. The helium-3 is "detected" through remote analysis for these favorable mineral and soil characteristics. Using data on the titanium ...


9

The oblateness of Ceres seems to indicate water. Moreover water geysers were recently detected by Herschel Space telescope. Hopefully we'll learn more when the Dawn spacecraft arrives February of 2015. Planetary chauvinists like to point out mass of the Main Belt is small compared to Earth or Mars. But most of a planet's mass is inaccessible. As we burrow ...


9

It is highly likely it was known that the upper stage would could be overshot into the asteroid belt, but it may be within the upper-bounds of expectations. The reason for this is that Elon commented in the Falcon Heavy post-launch press conference that the propellant left in the upper stage was "within 0.3% of expected values". This means they knew how ...


8

Shallow gravity wells with a healthy angular velocity are much more amenable to space elevators. The elevators can be be much shorter. The stress is much less so the tether could be an ordinary material like Kevlar. P. K. Aravind outlined the equations for an elevator's length and taper ratio: The physics of the space elevator. I attempted to incorporate ...


8

The Moon would be a much better place most likely. As you said, 220 pounds of Helium-3 in a mass of many many tons of rock, makes it so that even a few tons of equipment to be dropped on the Moon would vastly reduce the price to return it home. Lifting 220 pounds from the Moon to return to Earth is relatively easy, all of the Apollo missions did it, and then ...


8

There is an interesting podcast that I listen to - We Martians. Last Nov they had an episode that touches heavily on this. The episode is here: http://www.wemartians.com/home/015 and it goes into far more detail than I can, but here's a brief summary: The SHARAD (SHAllow RADar) instrument on the Mars Reconnaissance Orbiter used ground penetrating radar on ...


8

tl;dr: There's a fair bit of wiggle room in density estimates, macroporosity is a thing to consider, you could still feasibly find a lot of material on this rock I first want to clarify that asteroids are typed according to their spectral properties. In the case of 129 Antigone (at least according to the paper linked in the Wikipedia reference section), its ...


8

The only reason near-Earth asteroids still have water is that it's bound up in hydrated minerals where it's become part of the crystal structure of those minerals. Freeing it from those minerals requires baking it out of at high temperatures (up to around 500 °C), the most easily extractable volatile ices are all long gone due to heat from the sun. In ...


8

The most obvious type of equipment required will be some form of restraint system. While, for some reason, studies of hand-shoveling a tunnel to the center of an asteroid are not appearing in my search results, there have been numerous studies about EVA restraints for small bodies. This robot arm and foot restraint system, similar to those used on the Space ...


7

There are several issues at play here. Are the raw materials needed to be found on the moon? Can the raw materials be realistically harvested on the moon? Can the raw materials be processed into a rocket propellant on the moon? Are rocket engines which use this propellant feasible? Are there more suitable materials for this purpose to be found on the moon? ...


7

NASA actually have looked into mining the gas giants, http://mdcampbell.com/TM-2006-214122AtmosphericMining.pdf, this paper outlines some the methods they might use, whether they will or not is a different question. They were considering mining methods, of Uranus due to its relatively low wind speeds (compared to Jupiter, Saturn and Neptune, such as ...


7

I can think of three generalized trajectories, actually: “More direct” routes, by which I mean quicker than a plain transfer. More Δv is required, and thus more expensive. Unless you have live cargo or other radiation-sensitive materials, this will be rarely used. Hohmann transfers, which will be the route of only the most highly valued resources. Finally, ...


7

While AlanSE did a fine job of addressing it I think I can do a better job of addressing where she's going wrong: Yes, I think an orbit as she is envisioning exists. The problem is that Earth has mass and will pull it out of solar orbit. It won't be in that nice orbit when it hits. The closest you could theoretically come to a soft landing would be to ...


7

Short answer: Maybe, if you allow for an engine like used in the series. Long answer: The spaceships in The Expanse do not use Hohmann transfers. Instead they just start to accelerate continuously to the point of intercept with their target, flipping midway and deccelerating again. This reduces both traveled distances (because your path is far less arced)...


7

That's a one trillion dollars question! Proximity of near-Earth flybys of asteroids is largely irrelevant when it comes to feasibility of matching their orbit and rendezvousing with them, what is more important is their hyperbolic excess velocity with respect to Earth, and how much delta-v is needed to do that. There are many Athen, Apollo and Amor groups of ...


7

I came here with the same question. While rock pressure is one issue, I think the limiting factor is actually heat. The most recent paper I could find on Lunar temperature gradients is Nimmo 2012, which gives a gradient of 2.5C/km starting from 30C near the surface. As the deepest mine on Earth is apparently limited by a temperature of 66C, it follows that ...


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