Idiots. Diamond is not intrinsically valuable; carbon is not rare, and industrial diamond is fairly cheap. Humans (and in particular one cartel) set a high value on gemstone diamonds.
It's going to be cheaper to turn waste carbon into diamond here on Earth than it is to boost any sort of mining platform out to another planet or our own asteroid belt, and this will continue to be true for many many years.
The speculation is not merely about planets that are lightyears away. The speculation includes asteroids. The Google cofounders, and James Cameron, and others, are funding Planetary Resources, which will mine near Earth asteroids. They will be launching their first satellites in 2-3 years and plan on beginning mining operations in about 10 years.
I think you are being extremely shortsighted and rude to call people "idiots" when they speculate about mining the asteroids.
Edit: It saddens me that the top post in this thread contains such hate and name-calling towards someone with the imagination to think about the future. Come on, HN, you're supposed to be better than this.
Asteroid mining of other stuff is a separate issue.
(Likewise, quality isn't an intrinsic value of anything, either. Humans assign qualities to things. There is a buzzword called "quality" which means "homogenized reproducibility")
Turning matter from diamond to carbon-fiber, or anything else, takes much energy. This is why diamond is so hard to cut - the carbon atoms have very strong magnetic bonds, and separating them takes a lot more force than separating iron atoms when cutting steel.
Once there is a lot of it, the price drops. Anyone remember the Futurama episode where they go to the gold planet?
http://www.theatlantic.com/magazine/print/1982/02/have-you-e...
Whats more interesting is a planet made up of rare metals - that would still cause the prices to drop (this assumes the mining can easily generate lots of metal easily, transport costs aside), but can immediately be turned around into something useful.
The reason they're more expensive than, say, iron, isn't that they're rare but they're rather difficult to purify from each other. They share the same outer shell electrons (s and d), and what separates them from each other is their f-shell electrons. Those, however, are buried inside the other shells. So their differences are largely driven by differences in atomic radius, differences which are small in chemical effect.
Which is all to say that the cost of producing them wouldn't change too much in that scneario, even if you had access to a trillion tons of ore for free.
http://arxiv.org/pdf/1210.2720.pdf
It's reasoned guess. They know three things about the planet: its mass, its size (radius/volume), and its orbital distance. They also know some of the chemistry of the star it orbits.
From the mass and radius, they inferred the density of the planet is a lower than other rock planets. They can explain low density in several ways. One is a thick layer of low-density supercritical water on the surface. Very large, extremely hot "oceans". An alternative is low-density graphite or diamond inside the mantle.
What they show is that a carbon interior is plausible given the data. They model several things. For one, the planet's formation from a primordial dust disk -- given the star's chemistry, which is unusually carbon-rich, and physical models of how elements separate out in accreting to planets. And they model the planet's current interior, based on known physics. They can't directly observe the planet chemistry; they can only model it.
Where are the measurements from?
The planet's radius/size was measured photometrically when it passed between us and its star (an occlusion, like an eclipse). They don't have the resolution to see the planet, but they can measure the reduction in the star's brightness when it occludes, and hence how big of a cross-section it has.
http://en.wikipedia.org/wiki/Transiting_extrasolar_planets#T...
The mass was discovered by measuring the gravitational effect on its star. It is a very tiny effect -- it's too small to see any difference in the star's position. But small changes in velocity shift the frequency of its emitted light, and that can be detected. This is a very small effect: the star's velocity variation due to this planet is just 6.3 meters/second, and it was measured with 0.2 meter/second precision! That's how they know the mass to within 5% accuracy.
http://en.wikipedia.org/wiki/Radial_velocity_method
http://arxiv.org/pdf/1208.5709v1.pdf
The star's element composition is known by spectrometry -- measuring how much of an atom or ion is at its surface, by how much that atom absorbs light of a specific color.
http://spiff.rit.edu/classes/phys230/lectures/spec_interp/sp...
http://en.wikipedia.org/wiki/Spectrometer
You can do it yourself. Do you know why the sky is blue? Because blue light waves are scattered by molecules in our atmosphere. The light emanating from distant stars also interact with the molecules in the star and nearby planets etc.
Also wouldn't the light only show us what's on the surface? Or perhaps only the atmosphere? They seem to know there's diamond inside the planet.
(this is an honest question, while I am trying to make a point, I would actually like to hear other peoples opinions)
Something always seems off about the quality of their articles compared to the other (above average) content that usually makes its way to the front page.
