What else can you do with an Interplanetary Transport System?(antipope.org)
antipope.org
What else can you do with an Interplanetary Transport System?
http://www.antipope.org/charlie/blog-static/2016/09/what-else-can-you-do-with-a-bi.html
48 comments
It's a key part of the proposal. The propellant is shuttled over to the spaceship in orbit via multiple runs of a refuelling rocket.
I guess the downside of constructing or assembling anything anywhere but earth today is that it's going to be a lot more expensive and complicated. Perhaps once Mars has some critical mass the construction can shift to there as the gravity is lower.
The moon is farther away than orbit and also doesn't really have a lot in the way of accessible natural resources. Elon touched briefly on the topic of a moon settlement...
Despite all the talk of a space elevator I think it's still science fiction. Elon's plan is all based on existing technology...
I guess the downside of constructing or assembling anything anywhere but earth today is that it's going to be a lot more expensive and complicated. Perhaps once Mars has some critical mass the construction can shift to there as the gravity is lower.
The moon is farther away than orbit and also doesn't really have a lot in the way of accessible natural resources. Elon touched briefly on the topic of a moon settlement...
Despite all the talk of a space elevator I think it's still science fiction. Elon's plan is all based on existing technology...
I guess I was imagining more of an Interplanetary Transport System that was at least self-sustaining if not profitable.
The lack of resources on the Moon could be solved by finding an appropriate near-earth asteroid to mine. The ideal 1st candidate based on potential mineral wealth ($87 billion, but I don't believe those numbers are very accurate) and proximity to earth (a measly .1au, or 9 million miles during its solar periohelion :) is Anteru I believe.
Here we are, on the precipice of colonizing Mars in possibly my 80 yr old father's lifetime, witnessing perhaps mankind's greatest and boldest feat yet and I'm getting greedy and thinking "Yawn, who cares. Let me know when the Interplanetary TRADE System is profitable and indefinitely self-sustaining."
I'd try to visit Mars at least once . When it reaches a level of infrastructure and economic development of early 18th century British or other Euro colonies is when it's looking likely I would consider making a one way trip there.
The lack of resources on the Moon could be solved by finding an appropriate near-earth asteroid to mine. The ideal 1st candidate based on potential mineral wealth ($87 billion, but I don't believe those numbers are very accurate) and proximity to earth (a measly .1au, or 9 million miles during its solar periohelion :) is Anteru I believe.
Here we are, on the precipice of colonizing Mars in possibly my 80 yr old father's lifetime, witnessing perhaps mankind's greatest and boldest feat yet and I'm getting greedy and thinking "Yawn, who cares. Let me know when the Interplanetary TRADE System is profitable and indefinitely self-sustaining."
I'd try to visit Mars at least once . When it reaches a level of infrastructure and economic development of early 18th century British or other Euro colonies is when it's looking likely I would consider making a one way trip there.
What's the appeal of people living in orbit though? By that I don't mean industries that could happen there, but people actually having kids, growing up, and dying. I don't see the rationale for a permanent population in orbit anymore then we have one in Antarctica or a deep sea oil platform.
You more or less answered your own question. For example, let's say that Enceladus or Europa does actually indeed possess a subsurface liquid water ocean and becomes a colony. Further, let's also assume that a lot of the raw materials needed for colonization for both Mars and the moon come from mining the asteroid belt. Thirdly, let's assume that there is a decent amount of trade between Earth, Mars, and one of these moons.
When you're working on one of these stations, you're not a seasonal worker like an offshore oil driller. It takes ~5 years to travel to Jupiter, so travelling there is most likely a very long term work commitment. At that point, it makes a lot of sense to have some sort of permanent port instead of a work camp between Mars and Jupiter to stretch your space legs,, rest, refuel, resupply, seek entertainment and the company of others, buy whatever black market items are banned on Earth or other colonies, etc. Prostitution would likely make its way there to as it does with mining towns here on earth. These circumstances would be a very attractive economic incentive for some enterprising folks. In fact, if we ever settle anywhere beyond the asteroid belt, this would become inevitable. People with unbearable and untreatable joint pain may find zero gravity to be a panacea for other reasons why someone might opt for this.I'm just spitballing though and came up with this scenario in 5 minutes, so take what I say with a grain of salt :) I just think that if we become truly a spacefaring civilization, permanent habitation in space becomes inevitable for a litany of reasons.
Space travel is going to be possibly the most disruptive development in human history. I'm going out on a llimb here, but I think that new religions will spring up and instead of a pilgrimmage to Mecca, the destination may be to observe the rings of Saturn. Or some people may just fall in love with the calming white noise of a warp drive generator. A 5 hr loop of Star Trek's engine noise is my go-to deep work soundtrack :)
A lot of towns in the United States and globally started out as rest and refueling stops between major centers of trade. Why would this be any different? I think there are enough people here on Earth out of a population of billions who might actually prefer to live in that environment or just don't mind it in the face of striking it rich.
When you're working on one of these stations, you're not a seasonal worker like an offshore oil driller. It takes ~5 years to travel to Jupiter, so travelling there is most likely a very long term work commitment. At that point, it makes a lot of sense to have some sort of permanent port instead of a work camp between Mars and Jupiter to stretch your space legs,, rest, refuel, resupply, seek entertainment and the company of others, buy whatever black market items are banned on Earth or other colonies, etc. Prostitution would likely make its way there to as it does with mining towns here on earth. These circumstances would be a very attractive economic incentive for some enterprising folks. In fact, if we ever settle anywhere beyond the asteroid belt, this would become inevitable. People with unbearable and untreatable joint pain may find zero gravity to be a panacea for other reasons why someone might opt for this.I'm just spitballing though and came up with this scenario in 5 minutes, so take what I say with a grain of salt :) I just think that if we become truly a spacefaring civilization, permanent habitation in space becomes inevitable for a litany of reasons.
Space travel is going to be possibly the most disruptive development in human history. I'm going out on a llimb here, but I think that new religions will spring up and instead of a pilgrimmage to Mecca, the destination may be to observe the rings of Saturn. Or some people may just fall in love with the calming white noise of a warp drive generator. A 5 hr loop of Star Trek's engine noise is my go-to deep work soundtrack :)
A lot of towns in the United States and globally started out as rest and refueling stops between major centers of trade. Why would this be any different? I think there are enough people here on Earth out of a population of billions who might actually prefer to live in that environment or just don't mind it in the face of striking it rich.
Once the cost is low enough, the rationale is its cheaper to make new land than to buy land on a crowded planet. If we hit that point, you would expect massive space colonization.
Thankfully someone mentioned a Dyson swarm [1] in the comments :)
[1] https://en.wikipedia.org/wiki/Dyson_sphere#Dyson_swarm
[1] https://en.wikipedia.org/wiki/Dyson_sphere#Dyson_swarm
SciShow estimated you'd need to destroy all the planets to get enough raw materials to build a swarm.
https://youtu.be/GrM3f7Bil5A?t=185
https://youtu.be/GrM3f7Bil5A?t=185
We don't really need a full swarm, at least not until we can use it to compute something useful. Even Mercury, the smallest planet, has enough raw material to build more space stations and power-gathering sats than we know what to do with at present.
If you had a partial Dyson swarm right now, what would you actually use it for?
If you had a partial Dyson swarm right now, what would you actually use it for?
At least the basics of having shelter, food, and water. Maybe at some point we as a civilization could create matter from energy and then create atoms, then finally molecules of whatever we needed.
We would also probably want to live long healthy lives maybe even transfer our minds into other bodies or devices.
We aren't even a Type I civilization yet so there is lots of planning and inventing to do.
We would also probably want to live long healthy lives maybe even transfer our minds into other bodies or devices.
We aren't even a Type I civilization yet so there is lots of planning and inventing to do.
I would use it to build and accelerate Von Neumann probes to colonize the Universe.
So how many sunshades (or square meters of mirror foil) could we get to orbit to regulate global warming?
Suppose that you can build a reflector surface with a 10 micron aluminum foil (27 grams per square meter) and an additional 13 grams of support mass to keep it rigid/oriented, for a total mass of 40 grams per square meter. Near Earth but outside atmosphere the solar constant is about 1366 watts per square meter. That puts an upper bound on how much warming you can prevent per m^2; in reality the Earth's atmosphere and surface already reflect a fair part of that energy without absorbing it. If you send the reflectors to geostationary orbit they'll be in sunlight constantly, but I don't know if their full penumbra will actually fall on Earth, plus that reduces the deliverable payload mass. Instead let's make another unrealistic simplifying assumption for the sake of argument: pretend that the shade array goes to LEO but it's reflecting sunlight away from Earth 100% of the time.
At 40 grams per square meter of reflector and 1366 watts per square meter that's an upper bound of 34.15 watts per gram or 34.15 megawatts per tonne of avoided insolation. With one expendable launch of 500 tonnes to LEO that's an upper bound of 17,075 megawatts of avoided insolation per launch. In 2007 the IPCC estimated the net anthropogenic component of radiative forcing for the Earth system at ~1.5 watts/m^2, or 765,108,000 megawatts altogether (1.5 * 510072000 * 10^6 watts). Using the assumptions previously given, one maximum-payload launch could mitigate about 0.002% of anthropogenic radiative forcing. Adjust the achievable mitigation upward proportionately if you think that the shield system can be implemented with less mass and adjust it downward if you want to replace my optimistic upper bounds assumptions with more realistic (lower) ones.
At 40 grams per square meter of reflector and 1366 watts per square meter that's an upper bound of 34.15 watts per gram or 34.15 megawatts per tonne of avoided insolation. With one expendable launch of 500 tonnes to LEO that's an upper bound of 17,075 megawatts of avoided insolation per launch. In 2007 the IPCC estimated the net anthropogenic component of radiative forcing for the Earth system at ~1.5 watts/m^2, or 765,108,000 megawatts altogether (1.5 * 510072000 * 10^6 watts). Using the assumptions previously given, one maximum-payload launch could mitigate about 0.002% of anthropogenic radiative forcing. Adjust the achievable mitigation upward proportionately if you think that the shield system can be implemented with less mass and adjust it downward if you want to replace my optimistic upper bounds assumptions with more realistic (lower) ones.
The earth, as it turns out, is pretty big. I don't think that you can get meaningful amounts of sunshades into orbit via rocket launches from Earth, even really, really efficient rocket launches from Earth.
As a wild-and-crazy concept, doing the lunar space elevator thing that Stross mentions in his blog post would allow you to build a manufacturing facility on the moon that turned regolith into a sunshade and then ship them up the lunar space elevator and drop them off into Earth orbit at a moderately reasonable cost.
If you aren't too concerned about the mass of a sunshade, there are lots of ways to constitute them, so this seems like it would be one of the easier manufacturing jobs you might imagine locating on the Moon.
As a wild-and-crazy concept, doing the lunar space elevator thing that Stross mentions in his blog post would allow you to build a manufacturing facility on the moon that turned regolith into a sunshade and then ship them up the lunar space elevator and drop them off into Earth orbit at a moderately reasonable cost.
If you aren't too concerned about the mass of a sunshade, there are lots of ways to constitute them, so this seems like it would be one of the easier manufacturing jobs you might imagine locating on the Moon.
Gold is supposedly the most malleable metal. One ounce - the size of a quarter - can be hammered out to 10 square meters.
I'll let someone else do the math.
I'll let someone else do the math.
The radius of Earth (according to Google) is 6371 km
π * 6371^2 ≈1.28e8 km^2 = 1.28e11 m^2 = 1.28e10 oz of gold
So, you would need 800 million pounds of gold, which would cost (at current spot price of 1324.80/oz) almost 18 trillion dollars.
Gold is probably not the best material for this
π * 6371^2 ≈1.28e8 km^2 = 1.28e11 m^2 = 1.28e10 oz of gold
So, you would need 800 million pounds of gold, which would cost (at current spot price of 1324.80/oz) almost 18 trillion dollars.
Gold is probably not the best material for this
800 million pounds is about 360,000 metric tons.
The total amount of gold we have mined so far is somewhere around 170,000 metric tons.
So if you used all the gold in the world, you'd only have about half of what you need.
At the same time, I was surprised that it is even in the same ballpark.
The total amount of gold we have mined so far is somewhere around 170,000 metric tons.
So if you used all the gold in the world, you'd only have about half of what you need.
At the same time, I was surprised that it is even in the same ballpark.
Thanks for the math help :)
That's looks like the size to cover the entire planet and completely remove all sunlight. But to counteract global warming, we'd need a much smaller area. If it's 1%, we're down to a mere $180B.
I'm sure you're right that other materials would be far more economical. My gut says Aluminum.
That's looks like the size to cover the entire planet and completely remove all sunlight. But to counteract global warming, we'd need a much smaller area. If it's 1%, we're down to a mere $180B.
I'm sure you're right that other materials would be far more economical. My gut says Aluminum.
Given that the costs of global warming are talked in the trillions, this means that this silly thought experiment would actually be a rationally economical solution.
Which just illustrates how terrible global warning really is, I suppose.
Which just illustrates how terrible global warning really is, I suppose.
Regarding fun-in-zero-gee: velvet cargo nets. Sorted!
Seriously, doesn't the recent news about higher mortality among lunar astronauts throw all this talk about colonization into doubt?
http://www.nature.com/articles/srep29901
Seriously, doesn't the recent news about higher mortality among lunar astronauts throw all this talk about colonization into doubt?
http://www.nature.com/articles/srep29901
I mean, if that sort of long-term mortality risk is a big factor for the colonists, things are going really well. Even if all of Musk's plans work out, living somewhere as inhospitable as Mars (not to mention falling out of the sky at many times the speed of sound) will entail shouldering substantial near-term risks regardless. The hope is that there's enough smart people with a sufficiently weak sense of self-preservation.
The Airship to Orbit concept [1] caught my attention a while ago. There's something rather elegant about floating one's way to (almost) orbit.
[1] http://www.jpaerospace.com/
[1] http://www.jpaerospace.com/
#7 Lifting Coca Cola LED billboard
Railguns that could accelerate and dump pieces of metal anywhere in world from high orbit. Militaries would drool over the idea of controlled falling meteors for strategic bombing
I wonder what one might do with a few square kilometers worth of foil shaped like a concave mirror and a lens or two. Perhaps the atmosphere is too efficient at absorbing light, but an equivalent of frying ants with a magnifying glass sounds pretty scary to me.
https://en.wikipedia.org/wiki/Kinetic_bombardment
I think we would all be better off if we didn't develop even more effective ways of killing each other...
I think we would all be better off if we didn't develop even more effective ways of killing each other...
Ramen. We really need to get into primary schools subjects such as meditation, ethics, moral and "care for humanity" instead of having people get educated to go into military and "drool over weapons to kill more effectively".
At least in this case there are treaties that prevent space based weapons platforms.
Well, that would work if people/government don't break treaties of all kind on daily basis. Solution must be in roots not a patch on top of pile (of bullshit we created over time)
a) it's kind of hard to hide a launch system where the fueled-up booster stack on the pad weighs two and a half times as much as a Saturn V and the launch is visible with the naked eye from a hundred miles away.
b) There is a reason we don't use Trident D-5 SLBMs (or the Russian equivalent) for precision conventional explosive strikes on targets which otherwise require long range bombers with intricate in-flight refuelling arrangements to hit: something about not scaring the other folks with strategic nukes into thinking we've initiated a first strike and hitting the big red end of the world button.
TLDR: even the big guys don't mess with space-based or sub-orbital weaponry. The risk of a misunderstanding is non-trivial and the perceived costs are far too high.
b) There is a reason we don't use Trident D-5 SLBMs (or the Russian equivalent) for precision conventional explosive strikes on targets which otherwise require long range bombers with intricate in-flight refuelling arrangements to hit: something about not scaring the other folks with strategic nukes into thinking we've initiated a first strike and hitting the big red end of the world button.
TLDR: even the big guys don't mess with space-based or sub-orbital weaponry. The risk of a misunderstanding is non-trivial and the perceived costs are far too high.
That's nice but treaties have been broken and what can be done will be done eventually. It all comes down to power.
Are we trusting the militaries of the world won't make gray goo or 100% lethal bioweapons because those would kill everyone, or will that just happen because it can, no point in even talking about it?
Of course we can and should talk about it. It's important to at least theorize what others might realize in order to be prepared. That's all I wanted to add.
"we are so dominant in space I pity the adversary who would come against us" Lieutenant General Franklyn Blaisdell, Deputy Chief of Staff of the Air Force for Air and Space Operations
The system I described apparently does not contravene these treaties, see wiki someone posted above afterwards
Agreed. Incidentally, the game Planetary Annihilation uses kinetic bombardment as a game mechanic, and it's pretty cool. Also terrifying.
A railgun still obeys Newton's third law. The gun would need a mass much larger than the bullet, or it's the gun that will fly away from the earth (so it won't be reusable for future bullets). This makes putting the gun into orbit too costly, or else the bullets too small.
It's probably most cost efficient to de-orbit the entire satellite, and include a rocket that fires upwards when it reaches a certain low height, to make it exceed its natural terminal velocity.
It's probably most cost efficient to de-orbit the entire satellite, and include a rocket that fires upwards when it reaches a certain low height, to make it exceed its natural terminal velocity.
Yeah, the real "killer app" is throwing asteroids that are already in space on your enemies.
Most naturally dangerous asteroids (near passes) are being publicly tracked, so people would notice you attaching a rocket and nudging it off course. Bringing a whole new asteroid from the belt is feasible (or will be soon), but it takes a lot of time, so you need to do it in advance. But if you put an asteroid in orbit, astronomers (at least) are going to notice and ask questions, which they wouldn't do for a satellite with a cover story.
OK, the world will know, but if no one can stop it, that isn't worth much.
I expect an arms race in this area.
There are also plenty of rocks on the Moon, but I don't have a good feel for how practical weaponizing them would be.
I expect an arms race in this area.
There are also plenty of rocks on the Moon, but I don't have a good feel for how practical weaponizing them would be.
Assemble an Orion ie nuclear pulse propulsion ship in orbit. These can theoretically acheive .1c, Proxima Centari in 40 years (give or take).
I'm not sure there's any time in the near future where we're going to be allowed to loft that much fissile material into orbit, due to the risks of the takeoff exploding and spreading it everywhere. Personally I think the risks are overstated, but that doesn't affect the reality that we're not going to be able to do that any time soon. We're not going to have Orion drives until we can get the fissile material from space.
Also it's not clear to me that an Orion taking off from a very-near-Earth orbit is a good idea, either. I'm not sure how to reconcile apocalyptic-sounding fears about EM pulses from nuclear explosions with an Orion departing from LEO.
Also it's not clear to me that an Orion taking off from a very-near-Earth orbit is a good idea, either. I'm not sure how to reconcile apocalyptic-sounding fears about EM pulses from nuclear explosions with an Orion departing from LEO.
Space Data Centers -- we got tons of power, just need to figure out how to vent all that heat.
Turns out space is really cold.
But vacuum is a very poor conductor of heat.
I think you can have large radiator panels and circulate a cooling fluid or gas. Most (all?) of the cooling effect comes from infrared radiation.
I didn't watch all of Elon's presentation and I don't know if he mentioned this. However, I would think that a space elevator of some sort or a massive lunar manufacturing facility would be required to efficiently create all the components of an Interplanetary Transport System.. Upwards of 80% of the mass of going into space is just propellant to escape gravity. Even if the rockets are reusable, we won't truly be an interplanetary civilization until most of the components needed for space travel are actually manufactured in space or in extremely low gravity situations