"Terraforming" the Asteroid Belt

Tom Kalbfus · 2014-10-28 13:58:24

The Asteroid Belt is the next thing out from the Sun after Mars. What do you think is the most efficient way to create an Earthlike environment out of the material of the asteroid belt?

Terraformer · 2014-10-28 14:28:12

For most places, disassembling them and building free space colonies... in fact, if you want Earthlike, then that's what you have to do to everywhere except perhaps Venus, Saturn, Uranus and Neptune - if you're content to have +-10% Terran gravity...

Tom Kalbfus · 2014-10-28 16:18:02

There are other configurations besides the cylinder, ring, or sphere, if you discard rotational symmetry. How about a larger version of the interplanetary spaceship that provides centrifugal force for gravity. The bigger the better within structural limits. Imagine a dome in free space, suspended from a cable with another dome o similar size and mass on the opposite side. The idea is to trick the senses, make one seem to be standing on the surface of a planet. The horizon is 4.668318755 km away for myself since my eyes are 5'6" off the ground, from a second story window, 5 meters off the ground, it is 8 km away the minimum radius of the dome should therefore be about 10 km, for a person standing in the center of the dome, the edge of the dome will be about where the horizon would be for most people standing on the curved surface of the Earth. We could introduce rolling hills to make the horizon closer, Hills no more than 6 meters high.

The distance from Staten Island to Westchester is 54 miles, lets make it 60 This comes to 96 km, we'll make it 100 km. So lets say we have an island in this dome that is surrounded by water, the water extends outward from this 100 km radius island another 10 km so we have a dome with a diameter of 120 km. We hang this dome by 1200 km of diamond cable at the other end of which is another similar dome. So we have the approximate area of two New York Cities with building restrictions of two stories. Rotate this to provide 9.81 meters per second squared of centripetal acceleration. Mirrors reflect sunlight into the domes.

Last edited by Tom Kalbfus (2014-10-28 16:52:41)

karov · 2014-10-29 00:56:04

Tom Kalbfus wrote:

The Asteroid Belt is the next thing out from the Sun after Mars. What do you think is the most efficient way to create an Earthlike environment out of the material of the asteroid belt?

a topopolis

Tom Kalbfus · 2014-10-29 21:38:05

A topopolis is a very long O'Neill Cylinder which forms a ring around the Sun. One problem is how to get light inside, the standard three mirror arrangement of an O'Neill cylinder won't work with a topopolis, as it can't be oriented with its end facing the Sun with three mirrors opened to reflect sunlight into the opposing valleys of the cylinder.

My idea is somewhat more modest than this. Ever hear of a Banks Orbital? I have a variation of this that I call the Banks Orbiter Instead of having a small ringworld 3.71 million kilometers in diameter, instead we have a set of tracks, and a disk world with walls to hold in atmosphere, that levitates inside the track and makes a complete circuit around this track once every 24 hours to produce 1 g of centrifugal force. The neat thing about this is the track isn't passive, there is a wave in the set of tracks, the disk world sits on the crest of the wave as it travels above the tracks, the wave makes a compete circuit around the track once every 24 hours as the disk world rests on top of it. The disk is moving, the track is not, only the waves in the track are moving.

In terms of action reaction, the disk pushes outward on the track sustaining its circular path, in opposition to this, the track is initially moving inward as it meets the underside of the disk world, the disk world pushes outward on the track, causing a section of the track to be pushed back outward as the disk passes over, after he disk has passed over the track is expanding outward on a 24 hour cycle. the track is elastic, like a rubber band, it stretches and elongates for 12 hours, slowing down as it does so, then contracts inward rushing towards the center of the track to meet up with the disk world again to be pushed outward once more and the cycle repeats. the energy of the disk's outward push is distributed over 24 hours time, rather than having the track be strong enough to support this weight continuously, this saves on track mass. The bank's orbiter rotates once every 24 hours, its disk diameter is 20,000 km, the track is tilted by about 24 degrees from its orbital plane, and the orbital period for the entire track as it moves around the Sun is 2 years. Each half year is a full seasonal cycle for the inhabitants of the disk world. The climate is similar to the Earth at 45 degrees latitude. The tropics are a bit unhealthy for humans anyway, just look at the third world and all the poor people that live along the equator, where diseases like Ebola get cooked up.

Tom Kalbfus · 2014-10-30 21:14:52

As for the Banks Orbiter, you probably need two per track, to balance each other out, the wavelength would I tis case be half the track loop instead of the whole, the frequency would be 12 instead of 24 hours The shape of the orbiter track would be that of an oval. The disk worlds would be on the narrow part of the Oval opposite of each other, this would be the crests of the two waves that support them. The orbiter tracks would look something like this:

th?id=HN.607993839892041395&w=98&h=108&c=8&pid=3.1&qlt=90&rm=2 Initial position
th?id=HN.608026017788988881&w=165&h=164&c=7&rs=1&pid=1.7 After the waves and disk worlds have traveled 90 degrees of their mutual circle 6 hours later.

The shortest diameter would be 3.71 million km. The two disk worlds would travel in a circle and the oval would rotate with them, the disks always being on the narrow minimum distance part of the oval no matter what their orientation and always separated by 180 degrees in their circular path. This whole thing would orbit once around the Sun every 730.48 days or two years. The thing is, this is about the same distance as Mars is from the Sun, about 1.52 AU. So guess what? We can put a Banks Orbiter at Mars-Sun L4 and L5, 60 degrees behind and ahead of the planet in its orbit. We probably could reduce its axis tilt to nearly zero an have Martian style seasons based on distance from the Sun. Mars gets half the sunlight per unit area as the equator of the Earth, which on Earth is about the equivalent of 60 degrees north and south. Or else we could have two fresnel lenses focus Earth levels of Light onto each disk, the lenses would have to be about twice the diameter of each Disk World and would have to pivot in order to keep each disk world illuminated at Earth levels of intensity. 1350 watts per square meter.

It would look sort of like this:
th?id=HN.608026125162843512&w=207&h=207&c=8&pid=3.1&qlt=90&rm=2 but supported by stretchable cables in a loop instead of four elephants on the back of a giant turtle, and it would have walls about 100 km high at the rim, so no water falls.

Last edited by Tom Kalbfus (2014-10-30 21:41:02)

RobertDyck · 2014-10-30 22:00:15

O'Neill cylinder

Stanford torus

Bernal sphere

Tom Kalbfus · 2014-10-31 07:23:37

RobertDyck wrote:

O'Neill cylinder
http://upload.wikimedia.org/wikipedia/commons/thumb/1/16/Spacecolony1.jpg/800px-Spacecolony1.jpg
http://upload.wikimedia.org/wikipedia/c … 3edit.jpeg
Stanford torus
http://upload.wikimedia.org/wikipedia/commons/thumb/6/62/Stanford_torus_external_view_by_Don_Davis_AC76-0525.jpg/768px-Stanford_torus_external_view_by_Don_Davis_AC76-0525.jpg
http://upload.wikimedia.org/wikipedia/c … _torus.jpg
Bernal sphere
http://upload.wikimedia.org/wikipedia/commons/thumb/6/6c/External_view_of_a_Bernal_sphere.jpg/800px-External_view_of_a_Bernal_sphere.jpg
http://upload.wikimedia.org/wikipedia/c … ere_3.jpeg

If you like real estate above your head and inverted. Not having your neighbors above your head and perhaps spying on you with a telescope, gives you more privacy though.

Terraformer · 2014-10-31 10:14:24

Make it big enough, and the air will absorb all the light, stopping anyone from doing that. Still, if we're going where most of the (easily accessible) resources are, we won't be using sunlight, so there's no point having windows. Just have 5km of air above your head, before reaching the sunroof.

When it comes to space habitats built from asteroids and comets, I like Dyson Trees, but a small ringworld - maybe 500m across - doesn't sound bad either... just a small one, for a few families who want to be able to practise their cult in peace. Well, until the Patrol turn up to investigate, and the Marines land.

Tom Kalbfus · 2014-11-01 06:28:43

Terraformer wrote:

Make it big enough, and the air will absorb all the light, stopping anyone from doing that. Still, if we're going where most of the (easily accessible) resources are, we won't be using sunlight, so there's no point having windows. Just have 5km of air above your head, before reaching the sunroof.
When it comes to space habitats built from asteroids and comets, I like Dyson Trees, but a small ringworld - maybe 500m across - doesn't sound bad either... just a small one, for a few families who want to be able to practise their cult in peace. Well, until the Patrol turn up to investigate, and the Marines land.

The best way to have peace is to live by yourself, the more people you add to your community, the more likely you won't have peace, because some people won't respect the rights of others.

The larger the city, the more your rights and freedoms are going to be restricted, for the safety of the public of course. There are people in cities that will murder you, rob from you and so forth, that is why laws are required. Every drunk person who drives and has an accident takes away you freedom, because then the government reacts to that, regulates driving and limits your ability to use a car, for example. Small communities grant you the most freedoms, and communities on Mars, for example are likely to be small.

In a Mars colony of 100, a 14-year old might drive a Mars rover, and no one will bat an eye. There won't be enough 14-year olds to write a rule that they can't drive cars, and if the individual has demonstrated the ability to drive one safely, there is no reason why he shouldn't.

Terraformer · 2014-11-01 07:12:58

Small communities grant you the most freedoms? Try telling that to the people in SeaOrg...

Tom Kalbfus · 2014-11-01 10:28:39

What is Seaorg?

Terraformer · 2014-11-01 12:16:59

http://www.scientology.org/faq/church-m … ation.html

https://en.wikipedia.org/wiki/Sea_Org

Other cults are available.

Tom Kalbfus · 2014-11-01 18:18:10

I don't count a religious cult as a small community, neither would I count an Amish farming community, that is a cult too. Small groups of people may choose for themselves to live highly regulated lives, but the point is they don't have to.

Terraformer · 2014-11-02 03:36:43

I doesn't matter what you think, because the truth is, they *are* small communities. In which individual freedom isn't considered much.

But, nae true Scotsman would live in such a community.

Tom Kalbfus · 2014-11-02 07:13:56

Terraformer wrote:

I doesn't matter what you think, because the truth is, they *are* small communities. In which individual freedom isn't considered much.
But, nae true Scotsman would live in such a community.

They can't prevent someone from leaving, as they have no legal authority to do so! Anyway a religion is no a geographic community, it is a class of people, not a town!

Terraformer · 2014-11-02 07:50:52

Good luck leaving a space colony out at L5 Jupiter...

SpaceNut · 2014-11-02 09:33:39

Ok enough is enough lets get back to the topic of terraforming the Asteroid belt...

What do we know is there is minerals and water there but to the levels to create takes not only energy in the beyond our current means but also the funding to put thoses that would create such a colony there with the processing as well as construction machines...

Void · 2014-11-02 10:05:10

OK, I have had an idea now and then about Ceres.

It has enough solar energy to be solar powered. Presuming it is differentiated and has a world wide glacier at the surface that could be partially liquefied with heat.

I have wondered if a underwater synthetic gravity could be implemented.

I suggest multiple shells. The gaps between the shells filled with a fluid suitable. Then the innermost one spinning fast enough for sufficient synthetic gravitation. Suppose it required 4 shells, the outer one stationary relative to the surrounding water or ice. The required total spin being divided between each of the 3 shells as you go inward with visualization. So shell 1 stationary. Shell 2 at 1/3 required speed, Shell 3 at 2/3 required speed, and finally Shell 4 at the required speed. The spinning would generate heat, but the heat can be dissipated into the ocean or sea or lake to keep the water melted. One nice thing about an ocean on Ceres, is you can have a really deep one before the pressures become hostile to human life. So done that way, Ceres provides a 3 dimensional habitat that could be filled with such machines for synthetic gravity.

I would begin the process by crashing a Iron/Nickel asteroid onto the ice to both provide the metals, and to of course melt a body of water under the ice.

The method I previously mentioned elsewhere (And no one replied), would be to send an automated probe composed of a flying saucer shaped balloon. I should have a tether. and when it would arrive at the Iron/Nickel asteroid, it would use a method to anchor the tether. Then the spin of the asteroid would cause a deviation in the projected orbit of the asteroid and be so engineered as to intercept Ceres.

The reason I think it would work, is that when this balloon was opposing the solar wind, a bow shock would be more intense than when it was being aided by the solar wind. So, I think spin energy shed during opposition would be greater than spin energy added when it is running with the solar wind. And the balloon would not need to be pressurized except when it was first deployed and expanded.

Anyway so I don't quickly get the pillow over the face routine, I will say that by some other method also a Iron/Nickel asteroid could be diverted to strike Ceres.

Pictures referenced from:
http://en.wikipedia.org/wiki/Ceres_(dwarf_planet)

Ceres (bottom left), the Moon and the Earth, shown to scale

So having the potential for a very large population perhaps?

Solar panels over it all?

A space elevator seems reasonable to me. Ceres would be the perfect pseudo Earth with a very low gravity.

It would be a great asset to then provide support for mining operations all though the asteroid belt, and those minerals being quite an asset to a solar civilization I think.

Last edited by Void (2014-11-02 10:15:22)

Terraformer · 2014-11-02 11:01:43

Heh, I was thinking about terraforming Ceres today. I was thinking of giving it a 5mb atmosphere (N2/CO2?), then constructing space elevators with counterweight space colonies. I'd work towards constructing a torus of space colonies at the Cererean synchronous orbit. That would be the main habitation for the population. On the surface I'd build a worldhouse to get a 50-100mb atmosphere at the surface, which would allow for (engineered) plant life to thrive, and to have fish inhabiting water, as well as building shirtsleeve areas within that for parks and gardens.

I fully intend to lay claim to the planet at some point in the next couple of decades. I just have to build the Dragonfire first.

Void · 2014-11-02 11:56:30

That's an interesting plan.

What if you ran a electric current through your torus, like an induction motor stator. The upper atmosphere being ionized might be caused to rotate counter to the rotation of Ceres to a null speed relative to the sun (As a reference point). And you would have a magnetic field. Ideally, you would somehow get the power for that from the solar wind itself somehow. I have seen plans of how to harvest enormous amounts of energy from the solar wind, but I don't yet have a model for doing it in this case.

Alternately, perhaps an electric current can run through the plasma of the upper atmosphere. I have read that the University of Wisconsin is doing that in a fusion reactor proto type, so that there magnets don't have to be as big. Don't know if very thin plasma will conduct a current, don't know that it won't, don't know.

I think my plan of inhabiting the water would be a precursor to your plan. It offers levels of safety that later will not be needed as much because of the build up of local capabilities to counter mishaps.

Last edited by Void (2014-11-02 12:04:56)

RobertDyck · 2014-11-02 12:14:51

I wouldn't build a habitat as a centrifuge on any world. If you need that, you can't step outside to prospect or mine minerals. Build space habitats as a giant centrifuge: O'Neill cylinder, Stanford torus, Bernal sphere. They can mine asteroids for materials. But not on a world. Not a planet or dwarf planet. My hope is that gravity is sufficient to prevent microgravity effects on the human body. So 90% gravity on Venus, 38% on Mars, 1/6 on Luna, 1/7 on Ganymede, 1/8 on Callisto.

But you mentioned Ceres. That's awkward. Surface gravity is so weak that it's probably not sufficient to avoid microgravity effects. According to Wikipedia, surface gravity is 0.029 g. Also not enough to sustain an atmosphere. But enough to form a round body, which classifies it as a dwarf planet. Material will be differentiated. It's believed that metal asteroids formed in the core of an asteroid with sufficient gravity to differentiate material, and sufficient heat to melt metal. By today's classification, that would be a dwarf planet. So at some point in the early formation of our solar system, a collision broke apart a dwarf planet. Metal asteroids today are the core of that dwarf planet. So Ceres is what that other planet would have looked like. And that means Ceres most likely has a iron core. But Wikipedia says surface is similar to a C-type asteroids, so carbonaceous chondrite. At least what we can see with telescopes. So an interesting suite of resources.

Eh. I guess a centrifuge hab would work. Good luck with that.

Tom Kalbfus · 2014-11-02 13:04:25

I have a very simple plan:
First I'll look up the radius of Ceres on the internet:
Turns out that Ceres is 475 km in radius, and since Ceres is one of the larger asteroids, it is round, this is a very useful property for building a space colony out of it.
So what is the formula for centripetal force?

We know the value for the acceleration we want 9.81 meters per second squared
We know the radius for Ceres, 475,000 meters which is r.
The unknown we have to solve for is V and w.
V = (a*r)^0.5 = (9.81*475,000)^0.5 = 2,158.65 meters per second or 2.16 km per second.
The circumference of Ceres is given by 2*pi*r = 2,984.51 km,
a rotation over this circumference at 2.16 km/seconds would take 2,984.51/2.16 = 1382 seconds, a full rotation would take 23 minutes.. Now just imagine we built a track along Cere's Equator, a series of towers higher than the highest elevation along this path on Ceres. Building these tall structures on Ceres should be easy due to the low gravity, and basically we'd have to anchor these towers deeply into the surface of Ceres. Then we build the track and then the ring. The track is basically an O, through the center of which we build the ring the ring is supported by pins through the sides holding the sections in place as we construct it. When the ring is complete. We cool the superconductors at the top of each O and using electric motors we accelerate he ring to 2.16 km per second. I would suggest we make the ring cross section 20 km wide. The asteroid basically acts as a stabilize for this enlarged Stanford Torus, the towers hold it in place above the surface of Ceres as it spins. sprouting from each tower is a decelerator track, it basically decelerates a capsule released from the ring so that it matches the velocity of the Surface of Ceres and can then land.

Since Ceres is 2.8 AU from the Sun we need a ring shaped mirror Above Cere's North Pole angle at a 45 degree angle to incoming sunlight. The ring is in the shape of an oval with the dimensions 475/sin(45 degrees) = 671.75 km and the short dimension being 475 km, from the asteroid this ring mirror would appear as a circle. This would reflect light to a ring or mirrors suspended above Ceres surface and held at a 45 degree angle to incoming incident rays from the north and reflect light directly into the Stamford Torus from above. The mirror above Ceres' North Pole would be 80 km wide an curved to concentrate light onto the 28.2 km wide mirror surface above Ceres equator which would then reflect the light onto the floor of the 20 km wide Stamford Torus.

Luckily the axial tilt of Ceres is only 3 degrees, so we can treat this approximately as if it had no axial tilt at all, so this mirror arrangement works fine.

The interior of this settlement would look much like this:
th?&id=HN.608004293838439748&w=300&h=300&c=0&pid=1.9&rs=0&p=0

What do you think of this idea?

Last edited by Tom Kalbfus (2014-11-02 13:11:58)

Void · 2014-11-02 15:07:03

I think I like most of whats going on here. Yes, I guess the underwater synthetic gravity is a lot of fuss.

I do think I might have a better plan.

Suppose Ceres is a glacier covered worldlet (Most likely).

Then perhaps excavate a cylindrical hole with sufficient floor space to hold a toroid spin device. Put a lake in the bottom of the shaft. Depending from the toroid, a rigid metal continuous skirt which projects deep into the water. This holding a bubble of air. When stationary, the bottom of this boat would be touching water. But as you spun it up, most likely the bubble of air would take the form of a bowl, and the skirt would be impinged into the sides of the bowl.

I see that this could have stability problems, so it would have to be engineered well. I don't at this time know what the best form of it would be. I don't know how happy the water would be having that ring skirt passing through it at a high velocity. To aid in stability, the center of the disk could still float in water because it's relative speed would be small. The drag would be relatively small. The faster moving parts would be floating on a captive bubble of air. But the skirt ring would surely be moving at a quite high speed through the water. It is possible that it would be necessary to continuously pump make up air into the captive bubble and let some of it leak under the skirt ring. Then the device would be more like a spinning hovercraft.

I would imagine of course that the walls of the ice shaft would be covered with manufactured materials, and that a roof would be in place. Using tensile and compressive methods I suppose if you would want skylights. Otherwise if you put it deep in the ice you would be able to use gravitational counter pressure to hold the roof down.

Why? Just something to think through. Perhaps less building materials required? Perhaps less rocket monkey work. Good radiation shielding? Being able to put on a suit and work on the surface.

I'm not in a competitive mode here, Just offering options to consider.

Yes I think an atmosphere for Ceres is a very long shot unless very advanced methods were used. (Mega structure, ect.) But I don't mind if someone wants to try to figure it out. Perhaps a spinning magnetic field would not only keep the solar wind off, but would curve the escape path of molecules and turn them around to head back towards Ceres? But a lot of effort to try to make real estate that is not very good starting material for a surface biosphere capable.

Even if it could be figured out, I am not sure it would be the best bang for the buck.

Antius · 2014-11-03 14:02:41

RobertDyck wrote:

I wouldn't build a habitat as a centrifuge on any world. If you need that, you can't step outside to prospect or mine minerals. Build space habitats as a giant centrifuge: O'Neill cylinder, Stanford torus, Bernal sphere. They can mine asteroids for materials. But not on a world. Not a planet or dwarf planet. My hope is that gravity is sufficient to prevent microgravity effects on the human body. So 90% gravity on Venus, 38% on Mars, 1/6 on Luna, 1/7 on Ganymede, 1/8 on Callisto.
But you mentioned Ceres. That's awkward. Surface gravity is so weak that it's probably not sufficient to avoid microgravity effects. According to Wikipedia, surface gravity is 0.029 g. Also not enough to sustain an atmosphere. But enough to form a round body, which classifies it as a dwarf planet. Material will be differentiated. It's believed that metal asteroids formed in the core of an asteroid with sufficient gravity to differentiate material, and sufficient heat to melt metal. By today's classification, that would be a dwarf planet. So at some point in the early formation of our solar system, a collision broke apart a dwarf planet. Metal asteroids today are the core of that dwarf planet. So Ceres is what that other planet would have looked like. And that means Ceres most likely has a iron core. But Wikipedia says surface is similar to a C-type asteroids, so carbonaceous chondrite. At least what we can see with telescopes. So an interesting suite of resources.
Eh. I guess a centrifuge hab would work. Good luck with that.

If gravity is too weak to maintain healthy bone mass, one solution may be to put people into short rotation centrifuges for 1 hour a day. That would be relatively easy from an engineering standpoint and the literature I have read suggests that it mitigates bone demineralisation resulting from bedrest. And bedrest is a good simulation of microgravity so far as the human body is concerned.

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#1 2014-10-28 13:58:24

"Terraforming" the Asteroid Belt

#2 2014-10-28 14:28:12

Re: "Terraforming" the Asteroid Belt

#3 2014-10-28 16:18:02

Re: "Terraforming" the Asteroid Belt

#4 2014-10-29 00:56:04

Re: "Terraforming" the Asteroid Belt

#5 2014-10-29 21:38:05

Re: "Terraforming" the Asteroid Belt

#6 2014-10-30 21:14:52

Re: "Terraforming" the Asteroid Belt

#7 2014-10-30 22:00:15

Re: "Terraforming" the Asteroid Belt

#8 2014-10-31 07:23:37

Re: "Terraforming" the Asteroid Belt

#9 2014-10-31 10:14:24

Re: "Terraforming" the Asteroid Belt

#10 2014-11-01 06:28:43

Re: "Terraforming" the Asteroid Belt

#11 2014-11-01 07:12:58

Re: "Terraforming" the Asteroid Belt

#12 2014-11-01 10:28:39

Re: "Terraforming" the Asteroid Belt

#13 2014-11-01 12:16:59

Re: "Terraforming" the Asteroid Belt

#14 2014-11-01 18:18:10

Re: "Terraforming" the Asteroid Belt

#15 2014-11-02 03:36:43

Re: "Terraforming" the Asteroid Belt

#16 2014-11-02 07:13:56

Re: "Terraforming" the Asteroid Belt

#17 2014-11-02 07:50:52

Re: "Terraforming" the Asteroid Belt

#18 2014-11-02 09:33:39

Re: "Terraforming" the Asteroid Belt

#19 2014-11-02 10:05:10

Re: "Terraforming" the Asteroid Belt

#20 2014-11-02 11:01:43

Re: "Terraforming" the Asteroid Belt

#21 2014-11-02 11:56:30

Re: "Terraforming" the Asteroid Belt

#22 2014-11-02 12:14:51

Re: "Terraforming" the Asteroid Belt

#23 2014-11-02 13:04:25

Re: "Terraforming" the Asteroid Belt

#24 2014-11-02 15:07:03

Re: "Terraforming" the Asteroid Belt

#25 2014-11-03 14:02:41

Re: "Terraforming" the Asteroid Belt

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