This article talks about a theorized new class of terrestrial: carbon planets, possibly with layers of pure diamond and surfaces of crude oil.

Wow. I've always thought we were a little conservative in the way we think about extrasolar planets (though I've seen pieces suggesting gaseous iron - or even silicate - atmospheres for some of those torch-orbiters.)

I've been wondering about iron planets myself. After all, if you peel off the crust and mantle, to some extent the Earth is one - and asteroid 16 Psyche is also thought to be a lump of iron/nickel 250km in diameter.

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Fin
Skep-ti-cult® member #488-28303-790

Very interesting article indeed!



So, if these planets do exist, what kind of colours could you assume that they have? And what about surface reflectivity (is that albedo?)

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Imagine the erosional possibilities of wind-driven diamond dust - they could be real smooth and shiny...

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Fin
Skep-ti-cult® member #488-28303-790

Don't forget the asteroid that plowed into what is now Ontario, Canada, that is now one of the worlds largest nickel mines (and a major source of platinum group metals)!

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T. Anderson

My imaginary planet Ribblehead is supposed to be mostly carbonaceous chondite, and originally had a dry Venus-like atmosphere.
But it seems I was too conservative; this proposed new class of planets has carbon monoxide and hydrocarbons in the atmosphere as well.

Something suggests to me that this is the sort of environment which might occasionally give rise to primitive life or at the very least, self-replicating molecules. I could be life, but not as we know it.

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Wow! El Dorado and Shangri La had nothing on these

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Eagle Eye Observatory

Well....

1. Would it be possible for life to exist on these carbon planets?

2. What kind albedo could such a carbon planet be expected to have?

3. What would the interior look like? Molten carbides?


I realize that we know little about these planets, but maybe someone could make an educated guess?

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1. Life without water? seems unlikely; but I would be very happy to be wrong.

2 Probably like a brownish Venus, with hydrocarbons instead of (or as well as) sulphur.

3 Lakes and seas of fluid tar and pitch perhaps, in a weathered surface otherwise similar to Venus. A very hot version of Titan.

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I think we could also expect an atmospheric O2 content approaching zero. "Today's Fire Hazard Level is: 10,000%"

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Why shouldn't a carbon planet have water? Nobody expects it be PURE carbon (or even hydrocarbon) -- just much greater abundance of carbon and correspondingly less silicon.

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http://news.bbc.co.uk/2/hi/science/nature/3492919.stm
This is slightly off topic because it deals with an entire star, not just a planet. They think this former star is made of carbon, and compressed enough that it makes a diamond 4,000 kilometers in diameter. It's a solid diamond rather than just having layers of diamond in it.

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There are 10 kinds of people. Those who understand binary, and those who do not.

We sorta talked about this in this thread. The discussion was more along the lines of asteroid sized diamonds. Scrol down a bit.

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It's just one of those damn things of which there are many few. -- Dan Blocker

I am not sure;
from here-
http://www.universetoday.com/am/publ...s.html?1022005
I invented a carbon rich imaginary world, myself, a while ago; in it's natural, pre-terraformed state it was very Venus-like, because of a runaway greenhouse effect. I suspect runaway greenhouse effects are fairly common among carbon-rich planets.

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New Orion's Arm Site . The Starlark . Against a Diamond Sky (OA Novella Collection) . OA Flickr set

WoW humans are already asteroid miners and don't even know it.