A Building Suspended From An Asteroid..?

If you’re thinking this all sounds totally impossible, remember that only two years ago, the European Space Agency completed the Rosetta/Philae mission, which successfully landed a probe on the surface of a comet.
Um, no I didn't, did anyone here?

Why is it some architects don't seem to have a firm grasp on reality? Remember my posts about the architect who wanted to build an all glass wall cube home and balance it on its point. How about the one where the local architect put the windows at foot level and below in the stairwell of a local building.

Also see every 4th or 5th "Caption This" on CR4.

No mentions that I can see that they talked with any Engineers for a practicality or budget "reality" check. This has got "lets build the Deathstar!" written all over it again.

The 'DEATHSTAR' is literally more feasible! Still impossible; but, more feasible!

Yea, they worked out the math and logistics and it was possible (with a few small leaps of science and engineering required) but would bankrupt the whole world.

Next time someone asks for a project, they can list how many things about this won't work.

well for one... if it's not on the ground.. what's holding it up in this picture?

live there? never

It's in orbit, not having to travel through atmospheric gases it's able to maintain the required velocity, but we all know what happens when you attempt that kind of speed in Earth's atmosphere....and for that matter what happens when you are traveling that speed and enter the atmosphere...

Say isn't that your condo?

The Earthlings suspect nothing.....

Your satellite dish is pointed at a satellite in geosynchronous orbit. Your dish is always pointing in the same direction. If you ran a string from your dish to that satellite, would the portion in the Earth's atmosphere burn up? Why not? It's attached to an orbiting satellite moving at 3.07 kilometres per second.

In theory you could run your string. In practice, there is nothing on earth with a high enough strength to weight ratio to make the string out of. If there were, we could build a space elevator and not have to use rockets to go into space.

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

The question was rhetorical.

This architect is all hat and no cattle.

I like how they have a crane in microgravity....

That building and its crane are not in orbit and not experiencing microgravity. It is being built from the ground up and at the altitude suggested by that picture would experience gravity only slightly less (<0.5%) than that at sea level. It is a common misconception that astronauts in orbit are weightless because they have flown high enough to escape the Earth's gravity. In fact, at an altitude of 400 kilometres (250 mi), equivalent to a typical orbit of the ISS, gravity is still nearly 90% as strong as at the Earth's surface. Weightlessness actually occurs because orbiting objects are in free-fall. Orbiting objects are falling toward the Earth at the same rate as the Earth is curving away from them, thanks to their orbital velocity which carries them around the Earth's circumference. That building has no orbital motion and is not in free fall.

If 22,000 miles of cable are unable to hold their own weight, then the building will be in free-fall.

And shortly after that there'll be reports of insurance-company executives in free fall out of windows in conventional buildings.

Consider all the junk in Earth orbit whose velocity relative to those cables would give a pea sized object the kinetic energy of an artillery shell. With all the junk up there in orbit between that asteroid and LEO, how many weeks/months/years would you give those cables before one of them failed?

I can see some other scenarios becoming like Gerald McBoing Boing on a pogo stick.

how about 15 minutes!

You can't build something so long that's design to hang from the ground up. It would tax the hell out of the budget and change it's design to a wider base. Etc.

Yeah, no sh!t. In the words of Wolfgang Pauli, "Das ist nicht nur nicht richtig; es ist nicht einmal falsch!"

That is a true statement, somebody with more need for someone else's money, than any need to help mankind.

How about we get back to making really good, long lasting affordable dwellings for the developing world (that has not actually been solved yet), and at the same time, come up with minimalist infrastructure that supports these communities with water, heat, and light?

I am no so sure about solar panels being the "go-to" answer on that.

This is insane. For geostationary orbit to be achieved the center of mass must be 22,236 miles above the equator. Thus the cabling will have to be much longer or this asteroid will have to be much bigger. Then there are all of the torsional effects that will happen from wind acting on a 22,236 mile long lever arm. (I think Archimedes once wanted a lever like this.)

I wonder how this fantasy intends to handle sewage?

Torsional effects, sort of like a vertical version of this:

Thinking about Gallopin' Gertie and this preposterous 22,000+ mile long suspension cable... what would be the fundamental resonance of a cable this long; hours, days?

Several days I suspect. Consider that sound propagating through (for instance) structural steel would take more than two hours simply to travel from one end to the other; the torsional oscillations would take much longer. However, there could be considerable twisting over its length and so a given point on that structure could rotate many times each cycle. Now combine bending from differential winds and you have a whip.

Now that would be one hell of a sub-sub-sub-contra-bass note.

I haven't researched it, but was the frequency of the oscillation measured? I would think 30-40 Hz just from seeing the video. However, I don't know if the video is being played in "real" time.

30-40 Hz is 30-40 cycles per second. Are you quite sure?

30 Hz was the refresh rate of old analogue NTSC televisions.

How does one measure something that does not exist? A six string bass guitar has a nominal lowest note tuning of 30.868 Hz but has a length just short of most people. A 20,000 mile long cable should reach a far low resonant frequency than 30-40 Hz. Granted the tension will be much higher for this miracle cable which will raise the pitch from bass guitar tension levels but I still think this will be quite a low note.

Oh, or are you talking about the Tacoma Narrows bridge collapse?

I've watched that video literally hundreds of times (I showed it multiple times to virtually all of my physics and many other classes over a 26 year period). I believe you are off by a couple of orders of magnitude! It's closer to 0.3-0.4 Hz.

That architect apparently hasn't a clue what Earth looks like from geostationary orbit. He shows this:

When it actually looks like this:

As pictured, that asteroid is in low Earth orbit.

Okay - it is hung from a rock in geostationary orbit so that the building stays over the same location continually, eliminating the effects on the building that a rock actually circling the globe would have - devastating. But, we still have atmospheric air currents to deal with, and that building is definitely going to be in a jet stream at times. Also the air currents do not necessarily travel in the same direction at varying altitudes. Just hanging on cables, how will these effects be accounted for? I can see a lot of twisting and turning in the wind. The answer my friend is blowin in the wind.

Oh but no! The fool wants to orbit this asteroid at an inclination to Earth's equatorial plane so that the structure will trace-out an analemma, like a satellite in a so-called 'tundra' orbit. So that the tenants can enjoy a changing view?

This so-called 'architect' is flat out counting past ten.

Sure who wants to live in a stationary building....this would be like living on a constantly flying ship that invaded another country's air space on a regular basis...and if the building is hanging from an asteroid, what's holding the asteroid up? If it's turtles all the way down, is it angels all the way up?...and what's to keep airplanes from running into the building that is constantly changing location...How would you commute from the ground....No there's nothing about this that would work....

No, there is one thing about this idea that will work...

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Anybody gullible enough to invest in this idea should not keep their money.

"... and if the building is hanging from an asteroid, what's holding the asteroid up? If it's turtles all the way down, is it angels all the way up?"

What 'holds' a geostationary satellite up? When you read the piece, note that the asteroid orbits at 31,068 miles altitude, 8832 miles beyond the geostationary-orbit altitude of 22,236 miles. This places the aggregate structure's centre-of-mass at geostationary altitude. At that distance the asteroid would normally be orbiting at a slower orbital velocity. However, its connection to the weight of that structure allows it to orbit faster than it ordinarily would at that altitude. Now suddenly cut those cables and the asteroid will move outward and into a long elliptical orbit whilst that structure collapses into a tangled heap on the ground, or at the bottom of the ocean, as the case may be.

OK so what would be the orbital speed of the asteroid, and what would that equate to at say a 1 mile altitude for the building? What would be the max speed of the building? If we say that the max speed of the building is say 10 mph, the further you go away from the Earth's surface the less speed you need to maintain orbit...geostationary is ~22k miles altitude and speed is ~7k mph....

http://www.dummies.com/education/science/physics/how-to-calculate-a-satellites-speed-around-the-earth/

The altitude of the building makes no difference as long as the aggregate centre-of-mass is at geostationary altitude. The building having a ground speed of 10 mph means that the centre-of-mass is only slightly farther or closer to the Earth. The CoM's orbital inclination as well as its precise distance and direction relative to geostationary altitude will determine the direction and speed the structure is travelling relative to the Earth's rotation.

There is not a fixed relationship, moreover, between the asteroid's altitude and the mass of the building (including cables). A smaller asteroid farther out or a larger asteroid closer in, would have the same effect so long as the net centre-of-mass remains at geostationary altitude. That is the ultimate objective, and so to ask "What is the asteroid's velocity?" can be answered only when the other design parameters are specified.

I think it just means the military could use it as a high altitude aircraft carrier, except the fighters could not return to base, but at least they could launch one hell of a sortie from up that high. The other countries could take turns shooting missiles at this structure when it came around over head.

It might be a good place to store uncooperative politicians, and definitely defense attorneys.

And a gaggle of flat-earthers as the counterweight. See? They're good for something.

I see we are on the same page here. We need those folks with their feet firmly planted on something...

The piece originated with the Daily Fail, a little early for April Fool's day but maybe they've been suckered about the date as well.

Yes, these considerations and many more. Consider that top image, for example. Looks like it's floating above Manhattan at what, under a kilometre's altitude? Earth's radius at New York City's latitude is roughly 6369 kilometres.

According the article they plan to put this asteroid in a 'tundra'-style orbit such that the structure's trajectory traces an analemma, crossing the equator and back in a number of days. Neglecting the airspeed this implies, consider that, due to Earth's equatorial bulge, they would have to raise this structure more than nine kilometres to maintain that altitude above the surface as it crosses the equator. Earth's radius at the Equator is roughly 6378 kilometres. How will they do this without changing the net centre-of-mass and therefore the orbit? Move a massive counterweight on the asteroid-side of that cable assembly to compensate, meaning even more tension on those cables? As Earth is not a sphere they will be continually raising and lowering that structure and its counterweight to maintain altitude. I reckon a couple of days is very near the extensional resonant period of that structure. A yo-yo on a spring.

Now you are confusing me.

Are you taking this ridiculous idea seriously or are you ridiculing this farce with serious ideas?

Not so clear cut as that.

I enjoy exploring ideas, even ridiculous ones or, at least, ones not completely ridiculous. Much of this idea is hair-brained, to be sure, but it also has interesting components worth exploring. It is a takeoff of the space elevator idea, an interesting concept in its own right and not at all ridiculous - just technologically infeasible at the moment.

They'd also need something like that counterweight during assembly of the structure. Ignoring all the other flaws, the only way I can visualize construction would be to initially have the asteroid at geosynchronous altitude, and gradually move it out as mass was added to the building and cables, and of course continually lengthen the cable to lower the building, to keep the center of mass at geosynchronous altitude.

This whole idea is a takeoff from the space elevator concept, and so why not build it as one, first? A stationary structure, suitably anchored to the Earth, not one in that ridiculous analemma-tracing orbit (that's a whole new can of worms). Start, as you say, at the asteroid in GSO and add cabling, etc., that you will need for just the elevator, using thrusters to move the asteroid further out as necessary to maintain the CoM at GSO altitude. Once you have that infrastructure in-place, you then have a comparatively economical means to move construction materials up and down as needed without the use of rockets. Once it's built, release it making orbital and counterweight adjustments as necessary.

Of course the foregoing presumes a zillion other serious issues with this idea have been neatly solved, but it's fun to play 'what if and what would it take'? If somebody really wanted to try this, what sorts of problems would they have to solve, and what might some of those solutions look like? No harm in exploring an idea.

Right. Don't forget that that cable coming down through the atmosphere must be made of a non-conducting material to avoid discharging a major portion of the ionosphere.

GA!

But don't forget the forces from Jupiter, Venus, Saturn and Mars or you might offend the financially solid but feeble minded folks from investing. Thank goodness that feng shui does not care about inertial references or bank accounts.

{All kidding aside, Good Answer.}

Well if all the energy produced for the building was exhausted into hot air balloons, maybe we could have a floating city....With a small nuclear reactor you could stay aloft indefinitely...

A nuclear powered airship, Jules Verne would be proud....

https://www.extremetech.com/extreme/196114-nasa-is-developing-a-plan-to-explore-venus-in-a-manned-solar-powered-ariship

Those airships and that floating city in the background? Now that would be cool. Name it 'Stratos' after the city in STOS episode The Cloud Minders.

Imagine, let us say these balloons manage to stay at this altitude on a vacuum, meaning its centripetal and centrifugal force cancels out to zero perfectly then comes a bee and rest on it, what will happen?

Definitely those balloons will be heading downwards there after.

A balloon in a vacuum would not float. Bees cannot fly in a vacuum. Centrifugal forces are false forces.

I'm never sure if you're serious or playing a prank.

No, let us say those balloons are suspended by someone on space initially right there (static). Its acceleration due to the its rotation (centrifugal force that I meant) and (gravity that pulls it down) centripetal force cancels out. Ok, its a bad example, anyhow.

A balloon attached to that structure in the vacuum of space is dead weight. It has no more buoyancy in vacuum than the structure itself. Max altitude attained by a balloon is around 53 km/33 miles or about 180,000 feet. A balloon at max altitude, moreover, cannot lift its payload further. If it could, it would gain altitude, no?

If it is static (not moving), then there is no centripetal force required, and it's not in orbit. Gravity will pull it toward the nearest large object, Earth.

If it is in geostationary orbit about Earth, then it is hardly static, and the required centripetal force is just provided by gravity. the same would be true for anything (like a bee) added to it, as long as the thing being added has essentially the same orbit, so would have no effect on its motion.

GM, some of the stuff you come up with is hilarious. Keep up the good work!

More details....

https://www.csmonitor.com/Science/2017/0329/A-20-mile-long-spacescraper-dangling-from-an-asteroid-Could-it-work

This analemma extends from New York City's latitude to a point on the coast of South America. Now if the analemma is symmetrical about the equator, then that structure is traversing 80 degrees of latitude and back again in one day. If the analemma were a straight line (it's a figure-eight) between those two latitudes - 40N and 40S - that structure would travel 2 * 80/360 * 24,900 miles per ~24-hour period, for an average speed of 461 miles per hour.

But because the length of that figure-eight is longer than a straight line between those two latitudes, it is covering even more distance in that same period. At the top and bottom of that figure-eight, it slows down and so has to make up for that speed elsewhere in its trajectory, namely where the figure-eight crosses. I haven't run the numbers, but offhand I'm guessing that peak speed is something around 600 miles per hour, possibly more. Better bring in that patio furniture, Martha.

The article goes on to state that they will 'dock' that structure there in South America in order to replenish consumables. How? It is in continuous motion, several hundred miles per hour at a minimum.

I wonder how quickly aerodynamic drag will pull this absurdity out of orbit?

Is there any investors will to give me some money?

I know, right? This scheme has so many obvious problems that it boggles the mind. Problems these authors are flat out missing. Really they should have saved this as an April Fool's joke.

For instance, you're dragging what is basically a long rope through Earth's atmosphere at high speed. Now, assuming the thing is made of magical materials that somehow hold together (and the thing isn't dragged out of orbit), what of the rope's shape? It is deflected to one side, forming a curve, not one neatly hanging vertically as shown in the pictures (shhh - don't tell the investors).

Now imagine someone in their lounge room on one of the lower floors, everything tilted to one side, the angle possibly exceeding 40 degrees or so and assuming the structure isn't also rotating like the pendulum in an anniversary clock and the motion-sick occupants pinned to the outside walls.

Maybe part of the building is ejected when it hits the docking point, then is reconnected on the next go 'round....maybe part of the building is a rocket....

Speaking of reusable boosters...

Just because somebody can't afford their own private jet, doesn't mean they shouldn't be allowed to fly....

https://arstechnica.com/science/2017/03/we-may-have-just-witnessed-the-dawn-of-truly-commercial-spaceflight/

⇑ See the smiley at the bottom (hint, hint)? ⇑

AH... NO!

I'm still trying to figure out who would live in such a place and where the waste would go? Where do the consumable come from?

The views would be interesting to say the least, but getting shtuff too and from this megafailopolis would be a costly and dangerous proposition.

A place for the elite agoraphobic ?

A giant lightning rod in reverse? Who want to stand under it?

If they try to build it, you'll almost certainly get your Kaboom!

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Section 14 says nothing about banning religious argument as politics.

Islamoron!

What happened, buddy?

I'll wait for the space elevator first...

Where would they get the boulder?

From Boulder, of course. There's a big pile of them next to NCAR.

I don't know who originates the idea. I am pretty sure the asteriod belt is somewhere in between Mars and Jupiter.

Uhu, those people are probably rich. How much money does it take on a ton of material to be sent to space? Gazillion, perhaps?

I don't know, but this may seem near to reality than that.

No, the asteroid would fall down and crush the building. Next question?