Methane Explosion on Asteroid?

[Janet]

That's a good question! It's the main component of natural gas and as such is an energy source. So it would be for export to Earth. As another thread on this blog points out, demand is so down everywhere, for everything, due to our cursed economy, we don't need methane from space now, or any other of the very many riches we could reap from space. That's our main problem to exploration now. We've got the technology, we don't have the demand. My novel discusses this, I hope not too much. But it is a real contradiction now.

Meanwhile, if you wanted to do something practical about it, could all the great guys using this forum quit playing so many video games, find a nice girl and have about A DOZEN KIDS? Cause that's the best thing you could do for actual space exploration about now.

[crubs]

Meanwhile, if you wanted to do something practical about it, could all the great guys using this forum quit playing so many video games, find a nice girl and have about A DOZEN KIDS? Cause that's the best thing you could do for actual space exploration about now.

Yeah... That ain't happening.

I find it difficult to suspend my disbelief in such a scenario. I find it really hard to believe that earth would ever need methane so bad that it would mine it from asteroids. I mean, We could extract methane nearly-for-free from all the mounds of cow poop that factory farms put out.

However, there are serious considerations for mining asteroids for metals. They say asteroid mining could reduce the costs of some metals to practically nothing. Methane can also be refined into hydrogen by pyrolysis:

http://en.wikipedia.org/wiki/Sabatier_reaction#International_Space_Station_life_support

Hydrogen, in turn can be directly used to fuel nuclear thermal rockets without needing oxidizer:

http://en.wikipedia.org/wiki/Nuclear_thermal_rocket

You could have the mine operate as a metal-fuel mine simultaneously. It's a tricky balance between being scientifically accurate and trying to avoid bogging down the reader with hard science and excessive detail.

EDIT: Hydrogen is actually more explosive than methane, and careless pyrolysis is a fine recipe for disaster.

Edited August 22, 2014 by crubs

[Cirocco]

Oh, Mesons, thanks!! But it's two hundred pages, dear heart! I'll come post a link where you can get it, though, when it's done. It's called Run. That's not very original but the rest of it is. I only have two chapters left, this fight scene, and the very last scene where the good guys pull into their hidden asteroid in the Oort Cloud to build a new world not based on modern society, especially the modern economy, at all.

I think I used science in a pretty creative way in one scene. When the good guys rescue the miners and split, they are pursued. There's a little gun play but both pursuers and pursued are interrupted by a Solar Weather Warning that an unanticipated CME of catastrophic proportions is headed straight for them. The good guys are passing an asteroid which happens to be a water asteroid, common in space--a source of oxygen, water, and fuel. They analyze it quickly and just at the right second pulverize it with their lasers and plunge into the steam, and are saved, but the pursuers, not so much. Just like Exodus only not. (Water in any form protects from radiation--God bless Google.) Please don't tell me it's impossible, I'm only going for plausible!

Not impossible I think. It's an incredibly risky and desperate move which would require wide-area heat based weapons (probably explosives of some kind, some sort of ship-to-ship torpedo or something) to vaporise enough water but not dissociate it and do it fast enough before the cloud disperses too much. You'd also probably only absorb the radiation partially, but you might bring it down from fry-the-entire-ship-insta-death to not-quite-insta-death. The ship would probably still take heavy damage to the electronics and the crew would still require space-age treatment against the effects of radiation poisoning, but yeah, I think it might work. Simply putting a large asteroid between you and the sun would probably be a more effective shield, but if there's no large enough asteroid around, this is -I think- a plausible last-ditch desperation move.

But hey, desperation move, just barely making it, crawling out of battle bloodied and bruised but alive... makes for a hell of a dramatic exit

Also, while a nice girl would be very welcome, twelve kids is NOT on my list of things I plan to do in my life

Edited August 22, 2014 by Cirocco

[Cirocco]

Yeah... That ain't happening.

I find it difficult to suspend my disbelief in such a scenario. I find it really hard to believe that earth would ever need methane so bad that it would mine it from asteroids. I mean, We could extract methane nearly-for-free from all the mounds of cow poop that factory farms put out.

However, there are serious considerations for mining asteroids for metals. They say asteroid mining could reduce the costs of some metals to practically nothing. Methane can also be refined into hydrogen by pyrolysis:

http://en.wikipedia.org/wiki/Sabatier_reaction#International_Space_Station_life_support

Hydrogen, in turn can be directly used to fuel nuclear thermal rockets without needing oxidizer:

http://en.wikipedia.org/wiki/Nuclear_thermal_rocket

You could have the mine operate as a metal-fuel mine simultaneously. It's a tricky balance between being scientifically accurate and trying to avoid bogging down the reader with hard science and excessive detail.

EDIT: Hydrogen is actually more explosive than methane, and careless pyrolysis is a fine recipe for disaster.

Well earth might not need methane, but it's a nice source of hydrogen and carbon in outer space. That being said, you don't need to be mining for methane for it to be a problem. To draw the comparison with earth-bound mining: mine gas can be a problem in any mine if it leeches into the tunnels no matter what you're mining. If the asteroid colony is mining mostly metals and other minerals but the rock/ice/whatever material the crew quarters are dug out from contain lots of small methane ice pockets, then a slow build-up is possible.

EDIT: oooh ooh ooh, something I just thought of and which is a technique which is actually used in real life gas mining: it is possible for a layer of rock to have a huge amount of small pockets of gas which are completely sealed off. However, if said rock is subjected to a big shockwave or repeated tremors (in sci-fi that could be anything from ship weapons fire to a drill drilling too close to the quarters) then the rock fractures, the pockets start to crack open and voilà, a sudden gas build-up where there previously never was one.

Edited August 22, 2014 by Cirocco

[Janet]

Not impossible I think. It's an incredibly risky and desperate move which would require wide-area heat based weapons (probably explosives of some kind, some sort of ship-to-ship torpedo or something) to vaporise enough water but not dissociate it and do it fast enough before the cloud disperses too much. You'd also probably only absorb the radiation partially, but you might bring it down from fry-the-entire-ship-insta-death to not-quite-insta-death. The ship would probably still take heavy damage to the electronics and the crew would still require space-age treatment against the effects of radiation poisoning, but yeah, I think it might work. Simply putting a large asteroid between you and the sun would probably be a more effective shield, but if there's no large enough asteroid around, this is -I think- a plausible last-ditch desperation move.

But hey, desperation move, just barely making it, crawling out of battle bloodied and bruised but alive... makes for a hell of a dramatic exit

Also, while a nice girl would be very welcome, twelve kids is NOT on my list of things I plan to do in my life

Well, just start with one--kid I mean, naturally one girl. Try it out. You might go for two, the third will be a happy 'accident,' and so forth.

How they pulverize the water asteroid in the book: not with weapons exactly, they have escaped in a 'mining pod,' which I characterized as having all kinds of suchlike 'lasers' for mining, moving, turning, towing, and pushing asteroids around. I think it worked for plausibility. It IS dramatic. It's very visual, the ship in the midst of a great blue cloud of steam, the CME rushing by. Cue the music.

I swear, Cirocco, you could write your own novel. It is so fun.

[Janet]

I'm gonna think about this, about methane being an accidental thing, they're mining for something else. Because readers also might think the main source of methane is cows, and not realize it's the main component in natural gas and valuable in and of itself. Like, the miners could be mining for platinum and the methane thing happens just as you said, due to shaking, and poor design of the living quarters introduces it into the space, and then Will O. Yee (a miner who wears a mariachi jacket on off hours) lights a -- hmmm.

[crubs]

The asteroid could have oxygen produced by radiolysis of ice water. That mixed with methane would ignite with merely a spark.

[Janet]

The asteroid could have oxygen produced by radiolysis of ice water. That mixed with methane would ignite with merely a spark.

That is so poetic, sir.

[Tommygun]

What about an explosion caused by oxygen and carbon similar to Oxyliquit explosives.

Those two elements seem more likely to be found on asteroids than methane.

http://en.wikipedia.org/wiki/Oxyliquit

[Scotius]

Is your escaping ship equipped with nuclear drive? If yes, then its exhaust would vaporise that floating chunk of ice nicely At least in the world of fiction.

[Mesons]

The asteroid could have oxygen produced by radiolysis of ice water. That mixed with methane would ignite with merely a spark.

You mean photolysis? Any gas produced outside of a pressurized environment would be immediately lost to space due to negligible asteroid gravity. Likewise, any radiation powerful enough to photolyze water/ice molecules would not penetrate whatever shielding material the pressurized dome was made out of.

What about an explosion caused by oxygen and carbon similar to Oxyliquit explosives.

Those two elements seem more likely to be found on asteroids than methane.

Methane is the lightest stable molecule Carbon readily forms--due to the abundance of hydrogen and greater amounts of lighter elements during solar system formation, and especially since the melting point of methane is slightly above the boiling point of oxygen, much more methane would be found than oxygen in typical asteroids. Keep in mind that atmospheric makeup on the Earth is not very representative of the main constituents of the solar system! It's a whole different set of building blocks, which is a huge part of why I find astrochemistry so cool!

[Janet]

Is your escaping ship equipped with nuclear drive? If yes, then its exhaust would vaporise that floating chunk of ice nicely At least in the world of fiction.

I have been vague on this element. However, in the interviews that will follow the book's release, it might come up and then I will pull this out! 'Uh, well, the ship has nuclear drive, so of course it had enough power.' And then I will thank you, Scotius.

[Cirocco]

I swear, Cirocco, you could write your own novel. It is so fun.

No I probably couldn't. My brother got all the artistic traits, I got the science/engineer ones. I'm pretty good at writing individual scenes and coming up with stuff that makes me go "hey this is cool", but weaving it all together into one coherent story is where I flat out fail.

That being said I do have a couple files on my PC with written out scenes and ideas for a story/novel. Maybe I'll get around to actually putting it all together someday in the future.

[Janet]

No I probably couldn't. My brother got all the artistic traits, I got the science/engineer ones. I'm pretty good at writing individual scenes and coming up with stuff that makes me go "hey this is cool", but weaving it all together into one coherent story is where I flat out fail.

That being said I do have a couple files on my PC with written out scenes and ideas for a story/novel. Maybe I'll get around to actually putting it all together someday in the future.

Hey, let me recommend James Smith's You Can Write a Novel. It's simple, effective, I used it for Run​, it will help you structure the thing. Just don't buy it from Amazon PLEASE. Barnes and Noble or Abe's used books are two other great vendors and you can't beat Abe's prices.

You can write fiction! All those old distinctions (artistic vs scientific in particular) are bogus. Good science and good engineering is absolutely as creative as art. Smart people are smart, the rest is finding the right sources. IMHO of thirty years of teaching.