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Comment Re:science fiction (Score 1) 36

1% is too high, 100 ppm is the correct number for a "good" metals-rich asteroid. However, most of the value in an asteroid is the bulk materials. A ton of metallic asteroid is worth at least $5 million if turned into something useful in high orbit, because that how much it costs to deliver *anything* to that orbit today. the PM content is 100 grams, worth ~$3,200. Anyone who thinks PM is the reason to mine asteroids hasn't talked to a mining geologist about ore values.

Comment Re:science fiction (Score 1) 36

Right now, the best cost for getting stuff to GEO transfer orbit is ~$5000/kg. That includes propellant to complete getting to GEO, which is the desired destination. Hauling loads of asteroid rock to Earth orbit, and processing them for propellant could generate about 100 tons a year, thus worth $500 million/year, with 40-100 tons of starter equipment, and an additional 100 tons/year for each 20 tons more equipment (mainly more ore tugs to fetch rock faster). The trick is to do it at low enough cost to make a profit, but it's not orders of magnitude away, it's roughly profitable with reasonable development costs.

Comment Re:science fiction (Score 4, Informative) 36

I was one of the contributors to this plan, and one of the big misconceptions is that NASA is the only player in space. In reality, worldwide space industry was $323 billion in 2014, and NASA's $17.6 billion only represented 5.45%. Most of the 1250 active satellites in Earth orbit are commercial ones, and a lot of innovation is happening in that arena. For example, ion thrusters for boosting to synchronous orbit are standard procedure these days, using solar arrays 2.5 times as efficient as the ones powering the Space Station. SpaceX is working on recovering their first stage so it can be used again, while NASA is going backwards on the SLS solid boosters. In the Shuttle era the boosters were 2/3 re-used, on SLS they will be thrown away.

Comment Re:Asteroid Mining (Score 1) 64

Your question assumes a static economic situation, which is not what will happen. Launching whole factories to process the raw asteroid rock will cost too much at first. What you want to do instead is launch a starter kit of production machines. You use those machines to make parts for *more* machines out of some of the asteroid, plus some parts you bring from Earth. As your collection of machines in space grows, you can make a wider range of items, and need less from Earth.

In addition to growing the factory, you devote part of the output to products for sale. You start with the easiest products, like water and carbon compounds for fuel, because most anything in space requires some fuel, and they can be extracted by simple heating. You convert H2O + C --> O2 + Hydrocarbons, which is common rocket fuel mix. As you are able, you can start to make higher value items, like spacecraft parts.

Along this path, you may find products and materials you can deliver to Earth for less than the ground-produced version. A first such item would be "pristine meteorite samples". Collectors, jewelers, and scientists will pay large amounts for them, and they don't require any processing, just delivery. Precious metals are often mentioned, but they occur in ratios of 30-100 parts per million in asteroids, meaning you have to do a *lot* of processing to get them out. It may not be worth the trouble until much later in the industrial development. But whenever your cost gets below the competing Earth cost, then go ahead and do it.

Comment When Solar Got Cheap (Score 3, Informative) 325

> I disagree mostly because solar really didn't get cheap until the Chinese began to flood the market with panels, around 2010-2011 or so.

It wasn't the Chinese so much as solar grade silicon production. Prior to about 2009, demand for silicon for solar cells was smaller than for electronics. So solar piggy-backed on existing silicon foundries. But electronics-grade silicon is expensive (~$400/kg) because even one defect can ruin a chip. Eventually solar cell production got big enough that solar-grade silicon was worth it's own foundry lines. Defects in a solar cell just degrade the output a little bit, they still function just fine. The lower quality product was much cheaper to make ($18/kg last time I looked). Since the raw silicon was a major component of final panel cost, you had dramatic cost reductions for a few years.

Now we are back to more incremental cost reductions, but the panels are now so cheap that the "balance of system" (panel mounts, labor, wiring, inverters or transformers, permits, etc.) is the majority of the cost, and that's where work is being done to reduce them more.

Comment Re:Lying scum (Score 1) 303

> The real question is, is she bound for Prison or will Obama pardon her.

I'm sure Ed Snowden can give her some relocation advice :-).

The hypocrisy would be particularly pungent if she gets a pardon for mishandling classified data, and Snowden doesn't. The law only applies to peons, right?

Comment Re:Fuck precious metals- propellant all the way ba (Score 1) 61

> The thing is, we know for pretty high probability that (for example) Ceres has huge deposits of water.

The Carbonaceous Chondrite type asteroids contain up to 20% carbon compounds and water, which can be converted to hydrocarbons and oxygen, which is high-thrust rocket fuel. There are 13,000 known "Near Earth Asteroids", and we are finding 1500 more a year. NEA's are a lot easier and faster to return to Earth orbit, since we can use a Lunar gravity assist in both directions for our mining tug. Yeah, sure, mine Ceres eventually, but for starters the NEA's are the easiest to get to.

Comment Re:Space mining and kinetic bombardment (Score 1) 61

A properly designed space elevator (see my class notes for details: and slides: ) carries on-board propulsion for orbit makeup. It doesn't look anything like the pictures you usually see in the media, though. The continuous ground-to-GEO concept can't be built, even with carbon nanotube cables. It would be inefficient even if you could build it. More modern designs based on much shorter *rotating* cable systems are more efficient. Even an efficient modern design needs more traffic than we have today to justify the large construction cost.

Comment Re:Space mining and kinetic bombardment (Score 2) 61

> Unless you are able to use that material in space

That's the intent for early asteroid mining. Space industry is already $323 billion a year total, and a major consumable for all space missions (mostly satellites in Earth orbit) is fuel. Any future Lunar or Mars missions would add large demands for fuel to the existing traffic. But even just existing commercial satellites need fuel to get to their operating orbit and maintain position. If they run out of fuel, or parts break, the satellite has to be written off and replaced. A fuel depot and repair station would save billions a year. To run the depot you need a fuel supply, plus supplies for the repair crew. That's the first market for asteroid mining. Anything else will develop over time.

> Earth is where the money is.

Right. Communications, satellite TV and radio, GPS, weather, ground mapping. The money is down here, but the hardware is in orbit.

> but materials like iron

There is no shortage of iron on Earth. There's a shortage of iron in orbit, where it costs at least 3 times it's weight in silver to deliver. And so does anything else you want to put in orbit. Mining in space to use in space can retrieve 350 times the initial fuel load back to Earth orbit. As long as you find a use for a reasonable percentage of that returned mass, you win over launching it from Earth.

Comment Re:Time Value of Capital (Score 1) 61

Well, as a space systems engineer who does do cost calculations, the math goes like this:

Some asteroids, the Carbonaceous Chondrites, are up to 20% carbon compounds and water. These can be reformed to hydrocarbons and Oxygen, providing high thrust rocket fuel. An asteroid tug consumes about 2% of the returned mass as propellant. So the "return on fuel" is 10:1. It takes 2-3 years for the tug to do the return to cislunar space (near the Moon's orbit). 3 years gives a 115% rate of return. A tug is typically good for 5-8 trips before you have to replace the main parts (solar arrays and electric thrusters), so you can amortize the mass of the tug itself over that many trips.

Precious metals are a side effect to this, because they only occur at 15 parts per million, even in metallic asteroids. The main value is in the bulk components. Fuel is the easiest thing to extract, because that only takes heating, and concentrated sunlight can provide the heat. But you can find uses for the other 80% of asteroid material, bulk shielding against radiation if nothing else.

Comment Re:Not only space (Score 5, Informative) 61

> The appeal of asteroid mining is that they appear to be conglomerations of relatively pure ores

For Platinum-group metals, relatively pure means ~15 ppm in asteroids. On Earth, the vast majority of these metals sank to the core, because they are "iron-loving" (mix well with Iron), and that's where the Iron went. Metallic asteroids are the result of protoplanets large enough to *also* develop iron cores, but later collisions broke them up and exposed the core bits, where you can reach them.

Nonetheless, when you do the math, 15 parts per million is frosting on the value of asteroid rock. Most of it is in the bulk elements you can use in space directly. Space is already a $323 billion industry, so there is a lot of value in not having to launch stuff at great expense.

"Don't tell me I'm burning the candle at both ends -- tell me where to get more wax!!"