Author Topic: Asteroids as habitats  (Read 28309 times)

Re: Asteroids as habitats
« Reply #40 on: 01/03/2015 11:53 AM »
Hi Chris! Thanks for the input. I did some research on Coriolis Force (see "Principles of Clinical Medicine for Space Flight").  Most research on Coriolis Force complications and negative effects done was by the Russians in very small capsules about 10 meters in diameter. Even then they noticed that the Cosmonauts seemed to be adapting to the disorientation after a while.
 
What I envisioned was something about the width/diameter of 2 land sea containers side by side (about the size of a double wide mobile home here in the U.S.) about 6-8 meters wide and 3 high,  curved around in a cylinder (looking like a donut) and probably broken up into several separate living quarters but with one entrance for the free floating space hab. The structure would probably have an exterior diameter of 50 meters or so. At that diameter, based on what I've read, Coriolis Force shouldn't be an issue as a 6 foot (2 meter) tall man standing would have his head be about 23 meters from the central axis of the wheel/hab.
 For moons and asteroids square footage is probably not an issue as if we go there to stay we will have learned to use local materials to manufacture habs. They will almost certainly be underground so radiation and asteroid strikes probably won’t be an issue. Which means all they would need is something to seal in the pressure and heat (probably spayed on the exterior walls) and then just something to enclose their residence. I imagine it would be like living in a REALLY long, thin house, albeit, a curved one.
It's looking more and more like any large structures put in space in the near future will probably be pneumatically reinforced, inflatables as its easier and cheaper to ship them.  Probably filled with water (as it also shields radiation) possibly with an additive to automatically "clot" any small punctures. When frozen at 250 F below zero, (shielded from sunlight) water ice is harder than steel. If it was even 25 centimeters thick it would shield against almost all micro asteroid impacts.  The designs I have heard of proposed an exterior of frozen hard ice at -250F with another layer underneath that of liquid water (possibly with the “clotting” additive) so that if something does manage to puncture thru the hard ice layer,  the liquid layer below would be forced up by the vacuum and freeze/foam/clot  and seal the damage.
Larger inbound objects will probably be targeted and ablated with lasers before they can be a problem. NASA and DARPA are working on that sort of system as we speak to deal with all the space debris floating around in space right now.
  Blame the Chinese for a lot of that as they blew up a perfectly good satellite just for “target practice”. But mostly, to let everyone else know they can target and destroy any satellite they want, whenever they want. The problem with that is it risks the “Cascading Catastrophe” scenario where the debris from the destroyed satellite hits and destroys other satellites, their debris hits still more and so on and so on until all of near earth space is completely off limits to us and no satellites remain intact and no more can be launched.  The results would be catastrophic not just for a completely cancelled space flight of any kind but with the GPS satellites destroyed, airplane travel would effectively end for the foreseeable future.
I’m in California and got to get some sleep.
Cheers!
P.S. you may get a kick out of this, see my website @ donearlslates.com. I’m in the motion picture industry and live near Hollywood. My dad designed the modern slate/clapperboard.
Night!

Offline llanitedave

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Re: Asteroids as habitats
« Reply #41 on: 01/03/2015 03:01 PM »
I'm not convinced that we will be digging ourselves into asteroids. It gives some extra shielding potential, but it really makes artificial gravity a PITA, and frequent activity around an asteroid that you can dig down into will create a very dirty environment with asteroid dirt flying around everywhere.

My general opinion is that one is better off avoiding schemes like this and just use the asteroid for resources. For early habitats, bring inflatable habitats from Earth, surround them with properly sealed bags of gravel from the asteroid for shielding, and use a tether and counterweight system for artificial gravity in free space near the asteroid. The marginal benefit of digging yourself down early just does not outweigh the benefits of a pristine vacuum, easy access to sunlight, and the ability to plan ahead easily.

By digging yourself into an asteroid, you can run into unexpected problems, such as metallic dust from the asteroid cold welding itself into critical parts, sharp-grained dust getting on your solar panels and inside your habitats, unpredictable thermal changes, ect ect. I expect free space habitats with asteroid material as shielding is likely to become the superior option much like buildings above ground are generally both cheaper and more practical than buildings below ground on Earth.

I agree.  asteroids are resource bodies, living in one would be like living in a mineshaft that you're continually excavating around yourself.  Far better would be a free-floating habitat made of standardized parts, some of which might well be constructed using resources from the asteroid at hand.  The other advantage of the habitat is its mobility.  You can reposition the habitat to have the asteroid's bulk block it from the Sun in the case of a large mass ejection event.  Otherwise, that bulk will block a reasonable number of cosmic rays from all-sky sources.  And when the asteroid is played out, as they may happen after some period of mining (some asteroids may be more resource-rich than others), the entire habitat can be moved to another asteroid in the belt with a minimum of delta-V requirement.  This will allow us to exploit a huge number of asteroids eventually, rather than just having to choose one and stick with it.
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Offline Hanelyp

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Re: Asteroids as habitats
« Reply #42 on: 01/03/2015 08:05 PM »
If I were designing a structure to be built from raw asteroidal material, even from an iron rich asteroid, I'd assume the material had negligible tensile strength until examined and demonstrated otherwise.  Just carving a hollow in an asteroid and expecting it to hold together when you spin it up for artificial gravity or fill with air is unlikely to work out.

Offline QuantumG

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Re: Asteroids as habitats
« Reply #43 on: 01/03/2015 08:51 PM »
Well, you need at least 10 tons of shielding per m2 to protect your population from radiation. So, if your goal is a multi-generational colony, you will be tempted to at least start building inside the asteroid. The first problem you'll encounter is the availability of natural sunlight for growing crops. I think the solution to that is simply to genetically engineer crops for zero gravity and high radiation tolerance. This leads to remotely tended farming, which I think makes more sense anyway.

If you go with a cylindrical design with rotational stability, ala KalpanaOne, the surface area is 2πrh (ignoring the end caps) and h = 1.3r, so the total liveable area is 8.17r2 m2. If you consider 200 m2 to be the average living area of a family unit (which is quite luxurious), then r = √24.48n. Where n = 1200 say, r = ~172m. The removal of farming area from the colony reduces the required radius by almost a half.

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Offline Robotbeat

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Re: Asteroids as habitats
« Reply #44 on: 01/03/2015 09:02 PM »
Or just chemosynthesis. Methane and ammonia and oxygen (with minor amounts of other minerals) into edible food grown in big vats. Here: http://www.unibio.dk/

That could make up bulk of calories. Then, just grow the rest via LED growlights.


...Shielding is fairly easy. Grind up regolith/rocks to gravel and put it into sacks. (The sacks, if you prefer, can be made of rockwool produced from the regolith.) But rock makes poor shielding due to the low hydrogen content. It produces lots of secondaries, so you have to make sure you use LOTS of shielding to also stop the secondaries. But sacks of regolith scales pretty well if you're not going anywhere.
Chris  Whoever loves correction loves knowledge, but he who hates reproof is stupid.

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Offline QuantumG

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Re: Asteroids as habitats
« Reply #45 on: 01/03/2015 09:16 PM »
I think what it comes down to is the size of the cavity inside the asteroid. If you're tempted to rotate your habitat mere meters away then it will have the same failure mode as Lewis One - crashing into the shielding - but I think that temptation is driven by a lack of shielding material. If you have an abundance of material, which obviously is the goal of co-locating your habitat with an asteroid, then a static shield with some stand-off distance is more desirable than packing the shielding into the hull as your habitat doesn't have to carry all that weight, you don't have to expend power spinning it up, etc.


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Offline AlanSE

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Re: Asteroids as habitats
« Reply #46 on: 01/04/2015 02:04 AM »
How much do you reasonably think that removing the shielding requirement will decrease the mass per unit area metric? Various optimized shielding options in ideal orbits around Earth can be as low as 1 to 2 ton/m^2, according to papers that even you have recently shared on this forum. 5 ton/m^2 would be more probable, particularly if you didn't have a choice of the materials. Going all the way to 10 ton/m^2 seems pedantic because nothing about our biology says that we need sea-level shielding, and plenty of people live with less attenuation from the atmosphere anyway.

So let's assume we get rid of that. The floor still needs to support the artifacts that people like to live with. It also has to support the people themselves. If you take the shoe contact area of a normal person versus their weight, that itself is around 2 ton/m^2. Since the floor is rigid you don't need this specifically (local members distributes the weight), but you still need enough mass so that walking and running about won't deform the circular shape. If you wanted a ridiculous lower limit, it needs to be at least (70 kg)/(65 m^2) = 1 kg/m^2 to support the humans themselves.

Provided that you have a pressurized colony, the hoop stress will be the primary thing keeping the shape. You still need to resist the stress from the air itself, and this will probably dominate the loading. Sea-level pressure still "feels" like 10 ton/m^2 even if the wall materials weigh far less than this under the artificial gravity.

Quote
All we need to do is build peoples homes/workplaces/wherever in the shape of a toroid (donut) shape and put a spin on them so it creates a pull of 1 gravity inside. Surround the building with several concentric circles of metal or another sturdy material and float them on magnets. Put them at an ever increasing angle and speed, towards the house, and the resident can match speeds with the house or his/her workplace by simply stepping from one to the next till they get to the innermost ring that has a matching speed to their home/office/wherever. It would be like walking up or down steps.

Magnetic bearings are:

1) not naturally stable
2) best for high speeds

Concentric walls which have a staged relative velocity difference are about the last thing you would use in conjunction with magnetic bearings. This why O'Neil proposed one single track with magnetic bearings for super-massive rotating colonies that couldn't be supported due to limitations in material specific strength values (he was too early to be on the nanotube bandwagon). But he only proposed 1 stationary wall and 1 moving wall. Then you produced 1 g at a large curvature with magnetic bearings because that's what it works for. This scheme could produce huge areas along with virtually insignificant Coriolis forces - all while having no global material strength constraints.

The only problem is that for every square km of living space, you have to manufacture a crazy array of magnets which are all on active control of one form or another and probably use electromagnets. There is no magic bullet passive scheme to obtain magnetic levitation. You can use inductive windings, but you'll add more power dissipation and these will all only be conditionally stable anyway. For super large structures, I'm personally convinced that you'll also require active control of positioning of all the magnetic "rails" because the structure is so large it can't be thought of as a solid structure either.

If you take this scheme and just multiply it by multiple repeated layers you don't buy yourself anything. The appeal of magnetic bearings in vacuum is that they're mostly insensitive to speed. If the fields are mostly symmetric in the direction of motion, then the electrons can't tell the difference between one velocity and another.

Offline nadreck

Re: Asteroids as habitats
« Reply #47 on: 01/04/2015 05:29 PM »
Now I certainly have a biased interest in icy asteroids because I believe that in the next 50 years they will be the most valuable resource as source of water that can become fuel, breathable air, water which will make up a large part of grown biomass for food and fibers in extra terrestrial settlements. This, by mass, will be more in demand early on in our exploitation of inner system space than other materials, which will existing in some quantities on an icy asteroid anyway.

While I can imagine some romantic and colourful space created inside a hollowed out space iceberg, with atmosphere etc. an ice asteroid would not be strong enough to rotate for a significant centrifugal force, but, if one hollowed out a large space in an icy asteroid that one wanted to move, attached a very solid anchoring mass at the axis of a torodial spinning space station with a stationary central axis, you could use the excellent shielding properties of all that hydrogen in ice.  The spinning station could be engineered to be part of the orientation control of an asteroid (and whether you intended it as such you have to account for it in planing the effect of the spinning mass inside on the orientation/spin of the asteroid in question) and I only see such an asteroid being of real value placed (eventually) in orbit of Earth, Mars, Venus, one of the Jovian moons, or, in the very long run, somewhere useful in the asteroid belt as a station that provides fuel and other products to transiting ships.

I would envisage the hollowed out space to have an opening at one end large enough to bring the largest of ships in and plenty of space and non spinning (anchored to the central axis) working space to dock and support transiting craft while keeping them sheilded

Obviously to keep these asteroids from subliming away when they are brought to the inner system they will need some sort of reflector to keep the sunlight off the surface, to save mass that needs to be brought along it only makes sense to me that you constantly have active control of the asteroids orientation (besides which, however you moved it in the first place required orientation control along with what ever propulsion system was involved).
It is all well and good to quote those things that made it past your confirmation bias that other people wrote, but this is a discussion board damnit! Let us know what you think! And why!

Offline Nilof

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Re: Asteroids as habitats
« Reply #48 on: 01/04/2015 05:50 PM »
I think what it comes down to is the size of the cavity inside the asteroid. If you're tempted to rotate your habitat mere meters away then it will have the same failure mode as Lewis One - crashing into the shielding - but I think that temptation is driven by a lack of shielding material. If you have an abundance of material, which obviously is the goal of co-locating your habitat with an asteroid, then a static shield with some stand-off distance is more desirable than packing the shielding into the hull as your habitat doesn't have to carry all that weight, you don't have to expend power spinning it up, etc.

One interesting special case to consider is a Phobos colony. Because Mars takes up such a huge part of the sky, the Mars-facing side if Phobos is very well protected against radiation. You could have a tidal tether with a counterweight hanging down towards Mars to allow the habitat to be suspended over the surface with a few hundred meters of clearance. It could also provide torque for gyroscopic precession so that the direction of rotation of the habitat is constant with respect to the surface.

Mars and Phobos provide the shielding in this case, and you only need a thin annulus if you want to shield against the rest of the GCRs, which would admittedly not be too dangerous. This also means that a Kalpana One-type habitat can be made wider without being rotationally unstable, since you don't need heavily shielded endcaps.

The most efficient solution for power generation is likely to put solar panels on the tidal counterweight. The orbit of Phobos is tilted by 26 degrees to the ecliptic, so the sunlight there should be the same as for any low Mars orbit if it hangs down low enough. Better than at Ceres distance or Mars surface, but worse than LEO or high Mars orbit.
For a variable Isp spacecraft running at constant power and constant acceleration, the mass ratio is linear in delta-v.   Δv = ve0(MR-1). Or equivalently: Δv = vef PMF. Also, this is energy-optimal for a fixed delta-v and mass ratio.

Offline kato

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Re: Asteroids as habitats
« Reply #49 on: 01/04/2015 06:29 PM »
...Shielding is fairly easy. Grind up regolith/rocks to gravel and put it into sacks.
That bears the question whether it wouldn't be easier to first build your colony separately and grind up the asteroid to build a concrete-like shield around it. Way simpler than hollowing it out or anything like that anyway, because a tunnel-boring machine for a 1-km wide hole would probably have a mass of 10^6 tons by order of magnitude. Minimum.

We basically just need an asteroid with water, calcium, some metals and a whole lot of regolith - should be doable. Oh, and a couple dozen fusion reactors to power this whole thing, which can later be reused for the colony.

Just build a mining base on the asteroid from which you grow the basic colony structure into the open space "above" it, converting in-situ material as you go - sort of like building a skyscraper (in reverse, shifting it out) and heaping a concrete tower up to a couple hundred meters thick around it as a shield.


Offline QuantumG

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Re: Asteroids as habitats
« Reply #50 on: 01/04/2015 08:37 PM »
This seems helpful:

Quote from: Wikipedia
Apart from a few asteroids whose densities have been investigated, one has to resort to enlightened guesswork. See Carry for a summary.

For many asteroids a value of ρ~2 g/cm3 has been assumed.

However, density depends on the asteroid's spectral type. Krasinsky et al. gives calculations for the mean densities of C, S, and M class asteroids as 1.38, 2.71, and 5.32 g/cm3. (Here "C" included Tholen classes C, D, P, T, B, G, and F, while "S" included Tholen classes S, K, Q, V, R, A, and E). Assuming these values (rather than the present ~2 g/cm3) is a better guess. - source


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Offline mikelepage

Re: Asteroids as habitats
« Reply #51 on: 01/05/2015 03:17 AM »
I saw this video by the Australian science program Catalyst back when it aired and it came to mind just now - it mainly focusses on the use of Lunar regolith, but having had an email conversation with the Sydney-based lead scientist on this technique he informed me that they also think it would work with asteroid regolith.

It's relevant to any construction techniques being talked about here I think - the system is quite efficient with its use of the pneumatic gas to harvest regolith.

http://www.abc.net.au/catalyst/stories/4052664.htm

Online JasonAW3

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Re: Asteroids as habitats
« Reply #52 on: 01/06/2015 06:12 PM »
Actually, an O'neil tube or Stanford Torus built inside of an asteroid makes a considerable amount of senseso long as you line the cavity with a structure that can handle shifting masses.  If you physically attach the Torus or O'Neil Tube to the inside of the asteroid, regardless of how effecient the coupling joint is, some precession will occure with the asteroid itself.

If we're talking a rubble pile asteroid, unless the precession rate creates a centripedal force greater tyhan the Asteroid's gravity, then it should gradually reshape that part of itself that the rotating structure is in, to conform to the protective structure around the rotational mass.  The same is true of any mass beyond the location of the rotating mass.  mass will be lost by a spin higher than the forces holding the asteroid together, or will migrate to the centerline of the spin.

Iceball asteroids are much the same, but will change over a MUCH longer period of time.

Carbon Asteroids?  depends on if it is solid, tightly packed or just a dustball.

Nickel Iron?  Just mine them.
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Offline AlanSE

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Re: Asteroids as habitats
« Reply #53 on: 01/09/2015 12:23 PM »
Actually, an O'neil tube or Stanford Torus built inside of an asteroid makes a considerable amount of senseso long as you line the cavity with a structure that can handle shifting masses.  If you physically attach the Torus or O'Neil Tube to the inside of the asteroid, regardless of how effecient the coupling joint is, some precession will occure with the asteroid itself.

If we're talking a rubble pile asteroid, unless the precession rate creates a centripedal force greater tyhan the Asteroid's gravity, then it should gradually reshape that part of itself that the rotating structure is in, to conform to the protective structure around the rotational mass.  The same is true of any mass beyond the location of the rotating mass.  mass will be lost by a spin higher than the forces holding the asteroid together, or will migrate to the centerline of the spin.

Precession will not occur if the axis of rotation of the colony is aligned with the axis of rotation of the asteroid. So wouldn't you obviously design for this? Sure you would have some precession if you didn't have accurate survey equipment or use cruddy mechanical stabilization, which seem like ridiculous assumptions to make. You'll locate the anchoring points to form a line parallel to the asteroid's axis of rotation. You frankly don't need anything from the coupling joint aside from some accommodations for shifting masses, power cables, airlocks, etc. It's not a difficult problem to solve either. Before building the colony, rotate a test mass connected to a long pole which spans between the two contact points. Then, just like Earth pendulums, it will sweep a circle that tells you the relative rotation of the asteroid.

You will need some mechanical force between the colony and the asteroid to counteract its microgravity. Even a tiny acceleration will have a force like the weight of a dump truck when applied to the millions of tons of the colony. These forces also need to act through the colony's center of mass, so you need bearings on both ends which act symmetrically. But there doesn't need to be any change in the artificial gravity rotation vector. I think that would be a bad design, and almost always avoided.

Offline llanitedave

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Re: Asteroids as habitats
« Reply #54 on: 01/09/2015 03:28 PM »
The asteroid itself is likely to be precessing, and the process of construction will inevitably affect it in complex ways.
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Offline AlanSE

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Re: Asteroids as habitats
« Reply #55 on: 01/09/2015 05:00 PM »
On the Axial Precession of Asteroids

http://link.springer.com/article/10.1007/BF00653617

Quote
The observed fact that light changes of the asteroids exhibit no beat periods is interpreted as an indication that they do not wobble in space like spinning tops, but spin about only one axis (possibly — but not necessarily — inclined but little to the plane of their orbits). Since, moreover, the damping of three-dimensional rotation by jovi-solar attraction would require a time which is long in comparison with the age of the solar system, it is concluded that the present uni-axial rotation must represent a property preserved from the time when the asteroids were formed.

Why? Because here would be the equation for the precession in relative terms. By that, I mean the answer has units of 1/s, which is a metric of the change in relative angular momentum over time. This is what you need to ballpark the magnitude of angular change over some millions of years. In other words, this answers the question at hand without units specific to the body's overall size. However, the angular rate of precession does depend on the body's size because this is about tidal interactions with the sun.

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

Combining dphi/dt with Tx:



C and A are equatorial and axial moments, and the first term (C-A)/C is a measure of the equatorial bulge's moment relative to the total body. In other words, this is a geometric ratio metric. For our purposes, variable "a" is only different by maybe 1 AU versus 4 AU or so. In the big picture, this is practically the same. Spin rate is also the same order of magnitude, so it just about everything else.

I could easily agree that an asteroid would precess faster than what Earth does. But not by a factor of 1000s, and Earth precesses really slowly.

And even if we assume a huge colony on the order of 1 million tons in the middle of Phobos, that's less than 10 million times less than the mass of the entire body. There's no potential for impact to global mechanics unless we're talking about a tiny NEA, and those are unlikely to be rubble piles.

Offline veedriver22

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Re: Asteroids as habitats
« Reply #56 on: 01/09/2015 05:02 PM »
 I have a question regarding using rotation for gravity.   Would it not only work for things in contact with the floor?
I wonder if you jumped would you come down or would you just sail up to the ceiling.   Or if you were to throw something up what would happen.  If you were in a hollowed out asteroid and tossed up a baseball I am thinking the ball would end up on the other side of the asteroid.   

Offline meekGee

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Re: Asteroids as habitats
« Reply #57 on: 01/10/2015 12:54 AM »
I have a question regarding using rotation for gravity.   Would it not only work for things in contact with the floor?
I wonder if you jumped would you come down or would you just sail up to the ceiling.   Or if you were to throw something up what would happen.  If you were in a hollowed out asteroid and tossed up a baseball I am thinking the ball would end up on the other side of the asteroid.

Dynamics in a rotating reference frame is really screwy.  Specifically, your baseball will meet Mr. Coriolis on the way and end up somewhere else than you'd think.  It might even hit you in the head, but the motion path you'd perceive for the ball would not be a parabola.

There are some youTube vids that show similar behavior in centrifuges (or carousels)
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Offline Nilof

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Re: Asteroids as habitats
« Reply #58 on: 01/10/2015 08:16 AM »
I have a question regarding using rotation for gravity.   Would it not only work for things in contact with the floor?
I wonder if you jumped would you come down or would you just sail up to the ceiling.   Or if you were to throw something up what would happen.  If you were in a hollowed out asteroid and tossed up a baseball I am thinking the ball would end up on the other side of the asteroid.

Basically, inertia means objects want to move in a straight line in the nonrotating frame of reference. But draw any line from the inside of a circle and it will intersect the circle at some point. So objects do indeed tend to fall down. Those that don't or do so very slowly need high velocities relative to the floor, so that situation is more or less analogous to being in Orbit.
For a variable Isp spacecraft running at constant power and constant acceleration, the mass ratio is linear in delta-v.   Δv = ve0(MR-1). Or equivalently: Δv = vef PMF. Also, this is energy-optimal for a fixed delta-v and mass ratio.

Offline Paul451

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Re: Asteroids as habitats
« Reply #59 on: 01/15/2015 04:46 PM »
I have a question regarding using rotation for gravity.   Would it not only work for things in contact with the floor? I wonder if you jumped would you come down or would you just sail up to the ceiling. Or if you were to throw something up what would happen.  If you were in a hollowed out asteroid and tossed up a baseball I am thinking the ball would end up on the other side of the asteroid.

While in contact with the surface, you have the same tangential velocity as the ring. Basically, you are moving sideways. The floor is attached to the rest of the station, so it is pulled in a circle. From your position, the floor is being pulled upwards/inwards as you move sideways. As a result, the floor pushes you "up", and your inertia makes you feel like you are being pulled "down". That constant push "up", simulated pull "down", is what gives you artificial gravity.

So you are holding a ball, you let it go. It is in freefall, yes, but it is not stationary relative to the hub so it doesn't float, it already is moving "sideways" (just like you) with that initial tangential velocity. Because it is no longer being pushed up by the floor (or by you), instead it is free to move sideways in a straight line, but you and the floor move sideways and "up". So when the ball hits the floor, the you and the floor have rotated around to the path of the ball. So the apparent net motion is "down" to the floor.

Hang on, I'll throw in an image, probably easier to see.



Stick-guy in the middle is standing on the floor, but because the ring is rotating, he's actually moving sideways tangentially to the ring. If the floor wasn't there, he'd move in a straight line to the left. But because the floor is pushing him up and inwards, he instead moves in a circle.

If he drops his little red ball, it is free to continue in a straight trajectory as if the ring wasn't there, until it hits the floor. During that time, the floor will carry stick-guy around further, and so the ball will hit the floor just as his feet arrive. From his point of view, the ball fell straight down.

(In reality, because the ball is closer to the centre, it will be moving slower than the floor. So stick-guy's feet will move around slightly further by the time the ball arrives (shown by the faded image) hence the ball will hit the floor slightly to the right of stick-guy's feet. To stick-guy, it's as if the ball has drifted to the right instead of falling straight down.)

No idea if that actually makes things clearer.
« Last Edit: 01/15/2015 05:05 PM by Paul451 »