Asteroid/Moon mining

[D2DC]

With all the political jabbering going on this week, I thought I would start a thread for some scientific discussion: mining resources in space. I am curious how many people have heard of this? Until I saw some recent videos on the subject, I didn't really realize the potential, or how close we are to actually being able to pull something off.

Here is a good Bloomberg vdo to watch if you'd like to learn about it and/or discuss.

 

[Glurin]

I've heard of it from time to time and I know there were some promising looking projects in the works, but as far as how close anyone is to doing it without losing their shirt in the process... *shrug*

 

[D2DC]

Or, there is this one which really lit my pants on fire. I don't know how accurate the information is, as they are mostly just narrating an animated video instead of speaking to actual engineers. But, the potential for basically unlimited nuclear energy without all that pesky radiation is quite intriguing. Didn't realize that environmentalists should have been supporting rocketry/robotics/mining technology all along!

Anybody know how nuclear fusion of Helium isotopes works? 🤔

 

[krischan]

The moon is said to have significant amounts of Helium 3 because it's not protected from cosmic rays. He-3 plus Deuterium (H-2) needs little energy to start a fusion into He-4 plus a neutron (which decays into H-1 plus an electron with a half time of about 10 minutes). The other "easy" fusion is Tritium (H-3) plus Deuterium, but Tritium is radioactive with a half-time of 12 years (rather weakly radioactive per nucleus... but still enough to kill you if unprotected) and naturally available in small traces only (through cosmic rays only, IIRC). You would have to produce it artificially. 2x H-2 -> He-4 might be within our grasp as well.

The holy grail is fusing 4x H-1 into He-4 which would produce by far the most energy (that's what happens in the core of the sun), but that's currently out of what we can achieve.

Here's a graph of the average binding energy per nucleon (i.e. proton or neutron) for nuclei (i.e how much energy per nucleon would be needed to rip the nucleus apart into neutrons and protons):

To figure out how much energy is reased on a fusion, choose two or more source elements, add up their binding energies for all of its nucleons and compare it with the sum of binding energies of all the nucleons of one or more target element into which they can fuse. If the source has less, then energy would be released on a fusion. It's pretty much the same for fission, but our fission reactors use elements from the far right of the curve, with comparingly pathetic binding energy differences.

That's not all of it, however. What's not included in the graph is that you also have to produce enough energy to make it happen (i.e. to cause conditions at which the strong nuclear force overcomes the repulsion of the electric charges) and that's the challenge of it all.

 

[D2DC]

"Mining" it from the moon sounded pretty straightforward if its basically all at the surface. However, according to this study, getting/processing sufficiently large amounts of material would be the biggest challenge. The He3 content in lunar regolith is only 20ppm.. Transporting it back to Earth would be the "easy" part..

 

[jmervyn]

The moon is said to have significant amounts of Helium 3 because it's not protected from cosmic rays. He-3 plus Deuterium (H-2) needs little energy to start a fusion into He-4 plus a neutron (which decays into H-1 plus an electron with a half time of about 10 minutes). The other "easy" fusion is Tritium (H-3) plus Deuterium, but Tritium is radioactive with a half-time of 12 years (rather weakly radioactive per nucleus... but still enough to kill you if unprotected) and naturally available in small traces only (through cosmic rays only, IIRC). You would have to produce it artificially. 2x H-2 -> He-4 might be within our grasp as well.

The holy grail is fusing 4x H-1 into He-4 which would produce by far the most energy (that's what happens in the core of the sun), but that's currently out of what we can achieve.

Very interesting; I always was of the impression that our Moon wasn't worth exploiting, aside from all the idiots who would scream about destroying lunar culture & what not.

I paid what little attention I gave the subject to the concept of "capturing" outer space objects & mining them. Seemed like a fine idea but far beyond our real capabilities at this point.

 

[Glurin]

I knew about the Helium 3 on the Moon, but only in the context of using it to fuel rockets for maned missions outside of Earth orbit. The basic idea was that since the Moon has so much less gravity and could work as a fuel source, it makes a natural jump off point for much larger vehicles than we can currently launch from Earth's surface. So just use smaller vehicles to bring in supplies and materials to the moon, then construct and launch the larger craft from there.

 

[jmervyn]

I knew about the Helium 3 on the Moon, but only in the context of using it to fuel rockets for maned missions outside of Earth orbit. The basic idea was that since the Moon has so much less gravity and could work as a fuel source, it makes a natural jump off point for much larger vehicles than we can currently launch from Earth's surface. So just use smaller vehicles to bring in supplies and materials to the moon, then construct and launch the larger craft from there.

Makes me feel like breaking out my, "Space 1999" Lunchbox, it does.

(Kidding, of course - my mom wouldn't have bought it for me, and I couldn't afford my own. I lusted after one owned by a classmate though.)

 

[D2DC]

I knew about the Helium 3 on the Moon, but only in the context of using it to fuel rockets for maned missions outside of Earth orbit. The basic idea was that since the Moon has so much less gravity and could work as a fuel source, it makes a natural jump off point for much larger vehicles than we can currently launch from Earth's surface. So just use smaller vehicles to bring in supplies and materials to the moon, then construct and launch the larger craft from there.

Yes, we are supposed to be setting up (LOP-G) Lunar orbital platform (for docking/transitioning to lunar surface), and gateway for Mars etc missions. Use the orbital velocity of the moon, plus the orbital velocity of the gateway to launch long distance probes/ships farther into the solar system.

 

[krischan]

The big advantafe of a launchpad on the Moon is that it has no atmosphere and in particular a much more shallow gravity well. Remember the takeoff of the Apollo lunar module from moon. It needed a tin can with a small engine to bring it into an orbit around the moon while it needs a huge, multi-stage rocket for something of that size into an orbit around Earth.

The orbital velocity of the most relatively to Earth doesn't bring an advantage for a launch in comparison to Earth. Moon's distance from Earth = 384,400km. Multiplied by 2*pi is the length of the orbit. When dividing that by the duration of an orbit (28*86400 seconds), we get a speed of 1km/s. That's less than the speed of Earth's rotation near the equator.

Edit: 1km/s is actually twice of the speed of Earth's rotaton at the equator, but (1) it doesn't even out the other benefits of the Moon by far and (2) nobody noticed my mistake before I could fix it .

 

[Glurin]

Some interesting news recently.

https://www.forbes.com/sites/arielc...vys-ufo-fusion-energy-patent/?sh=64456f9f4733

Short version, the U.S. navy now has several patents for what has been dubed "UFO technology". One involves a small fusion generator capable of producing more power than a large coal or mid sized nuclear power plant. Another is for an "inertial mass reduction device", which immediately made me think of this:

Spoiler

Now, I wouldn't get my hopes up too much. Details are scarce, so there's every chance in the world that this is just a way to psych out certain foreign powers. We've done it before. But if they've actually got the goods, that would open up some pretty damn exciting prospects.

 

[jmervyn]

Details are scarce, so there's every chance in the world that this is just a way to psych out certain foreign powers. We've done it before.

Also, patent camping is a way to ensure an industry doesn't wind up being the sole province of a single company - when that happens the Gov't has to play legal games so as to not look like the villain it is when it rushes in & seizes the Intellectual Property rights.

So it may be that the tech isn't really "there", or that there have simply been developments in fusion which the U.S. wants to own as National Secrets. Not that we'd sell them to the Chinese, or anything.

Despite the movie "Thor", bureaucrats aren't eager to bend the laws in pursuit of an esoteric cause; we're far too lazy. We greatly prefer to have a friendly judge do the heavy lifting and later we claim we were just following orders.

 

[Glurin]

Something else to consider is that five years ago you could easily brush off something like this as pure science fiction and an obvious ploy. But now you kind of have to wonder about it if you remember the recent declassification of documents and video with our military going "Yup, it's real. That's genuine video from one of our planes of a genuine UFO. We got no friken idea what that thing is, but it's doing stuff that should be impossible."

 

[jmervyn]

Something else to consider is that five years ago you could easily brush off something like this as pure science fiction and an obvious ploy.

Well, *I* still can't believe I'm the only one excited that "Star Trek: The Voyage Home" was so prescient.

 

[LozHinge the Unhinged]

Well, *I* still can't believe I'm the only one excited that "Star Trek: The Voyage Home" was so prescient.

I don't believe you.

 

[jmervyn]

I don't believe you.

You never do. But c'mon, man, transparent Aluminum!!

It's Aluminum! That's TRANSPARENT!!

I did a bit more reading; apparently the finicky science geeks (you know how conservatives hate science & stuff) insist that ALON® AKA Aluminum Oxynitride is technically a ceramic rather than a "real" metal... but it's still a see-through Aluminum compound. I think the operational difference is that it must be cast, rather than poured when molten, which I guess is part of the reason I don't have drinking glasses made out of the stuff yet.

 

[Glurin]

Seems kind of silly to me to obsess about something like whether it's a metal or ceramic. Don't much matter what it's called as long as it can do the same function better and more efficiently. I think the only hangup on transparent aluminum now is the manufacturing cost. If we can just figure out a way to get that cost down, then we can start doing more with it than using it as a potential replacement for bullet proof glass or windows on submersibles.

Might make it a bit harder to create a good action movie scene by blowing away the bad guy through a window though....

 

[jmervyn]

Seems kind of silly to me to obsess about something like whether it's a metal or ceramic. Don't much matter what it's called as long as it can do the same function better and more efficiently. I think the only hangup on transparent aluminum now is the manufacturing cost. If we can just figure out a way to get that cost down, then we can start doing more with it than using it as a potential replacement for bullet proof glass or windows on submersibles.

Might make it a bit harder to create a good action movie scene by blowing away the bad guy through a window though....

Silly is an understatement. The fact that this stuff can be used for armored optics of all kinds, is already in use for deep sea submersible's (larger) windows, and is discussed as being ideal for outer space use is nothing short of astounding. I suspect the cost is fabrication more than creation, as it has to first be cast, and then specially polished.

 

[D2DC]

Anybody else psyched to see the Perserverence landing today?

 

[superdave]

Anybody else psyched to see the Perserverence landing today?

Touchdown!