Mining a Carbon Planet

[takemeout_totheblack]

A carbon planet is a world that, rather than being a primarily silicate based like earth, is composed of carbon in all its wonderful flavors. Such planets would have a crust composed of various carbon compounds such as graphite, various metal carbides, and good old fashioned diamond...kilometers of it.

What I would like to know if if there could be a somewhat scientifically hard (no pun intended) way of mining such a world, it's for a short story of mine.

http://en.wikipedia.org/wiki/Carbon_planet
Yes, yes I know it's wikipedia, but the articles in the references section seem pretty legit to me.

[Rossum]

I'm not an expert on such matters, but a planet made primarily of carbon (instead of silicon) should either have very little oxygen in its atmosphere or it would have runaway greenhouse gas problems like we've never thought possible. Well, maybe look at Venus which was almost exactly like Earth a few billion years ago until its slight closer proximity to the sun and lack of life resulted in runaway greenhouse gasses that raised its temperature to the point that it rains sulfuric acid, all water evaporated from the planet, and its atmospheric pressure is something like 90 times that of Earths.

Also, Carbon burns and turns into a gas like carbon dioxide or monoxide when exposed to oxygen, silicon turns into sand. Again, it would either need to have no atmosphere at all, or an atmosphere devoid of oxygen.

Again, I'm no expert on such things and if anyone else can tear into my reasoning then by all means do so. To play it safe, I would assume a mineable Carbon Planet would be one of the small rocky dry sorts of planets... like Mars, Mercury, or Pluto (before they decided it wasn't a planet). I'm guessing the whole idea for a Carbon Planet would be a planet that formed from gasses that for one reason or another had much more carbon than silicon.

As for problems... eh, graphite can crumble easily and leave lots of carbon dust on things and leave marks everywhere so things would look dirty alot. Graphite is black so it would absorb sunlight easier than silicon and the surface temperature would be hotter... snow and water would heat up easier as a result. There might be lots of diamond shards laying around depending on the geology... they could probably puncture tires or scratch up equipment if they get caught in the wrong place.


Other than that, I don't know. I'm imagining a low gravity world with little in the way of oxygen that gets unusually hot during the day and has black dust and diamond shards getting into stuff and messing with equipment. Depending on how rare silicon is in the area, it could be harder to get access to silicon for creating circuit boards or solar panels if the mining operation uses on-site fabrication. Though they could use substitute materials using carbon or carbon-based plastics.

[Uncluttered]

A few things to consider
1. Is the material going to be used locally, or exported?
If used locally, perhaps as building materials, then I think hydraulic mining would work fine.
You might be able to cut/burn the diamond with liquid oxygen.

if you plan on exporting the diamonds, perhaps as industrial diamonds, then you would just dig in with explosives and jack hammers.

2. Assuming export: What is the gravity at the poles? This effects launch cost.
I'm assuming this planet is metal poor, or the crust was molten for much longer than earth was.
If the planet is metal poor, the density is less than earth.
The relatively low density, would give you a larger diameter for the same mass as earth, gravity at the poles would be roughly the same IIRC.
However, at the equator, the gravity will seem much, much lower depending on rotation.

If the planet has earth density, and is just metal poor at the crust, It may have massive diamond mountain ranges at the equator. Tall equatorial mountains will reduce launch costs.

3. With large tracks of clear diamond, this planet might actually be very easy to paraterreform..sort of.
Diamond structures will let in the light. If you tunnel underground, you have a world under skylights. The diamond should protect you against meteorites, poisonous atmosphere, and some radiation.

Unlike regular terraforming, paraterraforming has a quicker payback.
Here's a link describing it.
http://beyondshuttle.blogspot.com/2010/ ... -1992.html

[takemeout_totheblack]

Actually, according to the page and its sources, such planets would not be nearly as metal poor as you might think. Such a world would be just as metal rich as a sillicon planet, the only difference being a far greater abundance of carbon. The substitution of one element in a planet's make-up doesn't exclude the presence of any others just because. So you're probably looking at the full spectrum of carbides and a possible substrata of diamond that'll pop up here and there, so I don't think drilling is going to be terribly productive. As you said, blasting and concussive tools like jack hammers would probably work, as would chemical based mining.

[Junghalli]

Actually, according to the page and its sources, such planets would not be nearly as metal poor as you might think. Such a world would be just as metal rich as a sillicon planet, the only difference being a far greater abundance of carbon.

IIRC carbon planets would form if the primordial gas cloud had more carbon, leading to large amounts of carbon being bound in forms that are less readily dispersable (by virtue of having higher vaporization temperatures) than the CO and other simple forms that most primordial carbon in the solar nebula would have ended up in. So yes, carbon planets would form out of gas clouds that have more heavy elements than the primordial solar nebula and so logically could easily have large amounts of metal.

[Zixinus]

I'm not an expert on such matters, but a planet made primarily of carbon (instead of silicon) should either have very little oxygen in its atmosphere or it would have runaway greenhouse gas problems like we've never thought possible.

What if its sufficient distant from its sun that it would barely heat the planet?