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/sci/ - Science & Math

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6265203 No.6265203 [Reply] [Original]

Why can't this idiot idea work.

>> No.6265207

Wouldn't the wire need to be pretty strong?

>> No.6265209

>>6265207
nah, fish line should work just fine

>> No.6265210

well it might be kinda hard to grab a hold of the wire as its whipping through the atmosphere. repairs would be a bitch. it would probably snap under its own weight seeing that it's thousands of miles long. just getting the wire to the moon would be crazy because of its size and weight. that's all I could think of in 2 mins.

>> No.6265214

>>6265207

It only needs to support the weight of the wire itself and whatever weight is on the end of the wire. Actually it would be less than that because of the space between the earth and moon without gravity

I just kinda threw this idiot idea and diagram together when me and my friend were suffering from insomnia induced drunkness

>> No.6265221

>>6265203

>imagine that big fuck-off weight zooming round the world, swattin' down planes, birds and shit.

>imagine the idiots using it for target practice every day

>imagine the wire snapping and that weight becoming a massive fucking wreaking ball hurled my the moon's momentum.

>> No.6265219

>>6265210

Who says you need to grab it, do the same process with a platform instead of a weight and you could land a helicopter on the moving platform

Also there are plenty of industrial wires that support more weight than they weigh, and the moon-end would much lighter anyway

>> No.6265222

>>6265221

>Imagine if planes had to avoid other planes moving in the sky

>imagine if a plane ever fell put of the sky

>> No.6265229

>>6265203
The Earth is also rotating as this happens, so the wire would whip around the entire Earth in ~1 day.

>> No.6265230

Distance between Earth and Moon varies, the length would need to adjust.

>> No.6265231

what would be the point of this?

>> No.6265234

Great idea op. I was skeptical at first but after running some back of the envelope calculations with just polypropylene rope. It appears you only have about a 1 to 9 overweight to strenth ratio to overcome. youll need a rope that can hold 1 ton of weight and weigh less than one tenth of a kilo per 200 meters length. which is a lot easier than the space elevator teether requirements. I think you may have the awnser.

>> No.6265236

>>6265229
it would probably be so loud when it went by.

>> No.6265240

>>6265214
>Actually it would be less than that because of the space between the earth and moon without gravity

You better be fucking kidding me

>> No.6265241

>>6265203
That rope would be subjected to a lot of drag on the earth side.

>> No.6265243

>>6265203
The logistics of such a wire even being made are ridiculous. It'd be hard to pull of a space elevator - Imagine making something hundreds of times longer than that.

>> No.6265258

The Moon isn't geosynchronous. Strapping it to the Earth would wrap the planet up like a nerd on a tetherball pole.

>> No.6265270

The Earth spins

>> No.6265273

>>6265258
>>6265270
>didn't read the picture

>> No.6265277

>>6265243

Are you really implying that we as human beings can't make a really long wire?

Fuck I'm sending this message through hundreds of thousands of miles of wire to reach you

It wouldn't be easy but it wouldn't be impossible

>> No.6265278

you forget space debris which could cut the wire at any time

>> No.6265279

>>6265231

I think OP is saying that the same principles could be used to move things into space, kinda like a space elevator

>> No.6265282

>>6265203
You would need one hell of a cable.

>> No.6265286

>>6265282
A cable with a very high IQ.

>> No.6265290

>>6265240
Welcome to /sci/

>> No.6265294

>Elliptical orbits
That is all.

>> No.6265298

>>6265203 no.
>>6265207 Ideally, depending on 'what' and 'how much' you want to accelerate up the "wire".
>>6265210 Can't because of >>6265294

>>6265214 not easy because of >>6265294

>>6265219 Nope because of >>6265294
>>6265221 only some days because of >>6265294
>>6265222 could be calculated because of >>6265294
>>6265229 no because of >>6265294
>>6265230 yes you agree with >>6265294
>>6265231 just leave
>>6265234 ... I don't even.
>>6265236 >>6265294
>>6265240 I'm sorry you have to put up with retards.
>>6265241 Problem? maybe >>6265294
>>6265243 and that changes due to >>6265294
>>6265258 Kind of.
>>6265270 ...
>>6265277 Not in our life time.
>>6265278 less of a problem than >>6265294
>>6265279 Maybe.
>>6265282 True.
>>6265286 Even more true.
>>6265290 Leave.
>>6265294 > Elliptical Orbits
/thread

>> No.6265315

>>6265214
>without gravity

>> No.6265335

Even if this works how is it a solution to space travel, it doesn't improve our ability to go somewhere we can already go at all.

>> No.6265487

Actually, the moon doesn't always have the same face towards the earth.

So you can kiss your idea goodbye right here.

>> No.6265627

>>6265487
The moon is tidally locked, so yes, actually, it does. I'm more concerned with the fact that in the drawing the moon is upside down.

>> No.6265671

>>6265229
Yeah, this is the main problem. The platform/weight would be moving at near 1000 mph. It would heat up and cause all sorts of problems. Also, this would actually create a drag force in the atmosphere and would actually change the Earth's rotation. It might be only a very slight amount per day, but the effect would be present every single day, forever.

>> No.6265674

>>6265294
So put a motor on the cable that retracts/extends it as needed. Still too many other problems, though.

>> No.6265673

>>6265335
We could tap on it to talk to the moon

>> No.6265677

>>6265234
I'D like to see those calculations

>> No.6265720

>>6265240

Well although it isn't zero, it would be less than normal

F=Gm1m2/r^2

>> No.6265724

>>6265203

It takes 29.whatever days for the moon to go around the earth. So by the time the moon spins once, the earth has spun almost 30 times. Seems like some serious sheering. Kind of like dragging an anchor through water without it hitting bottom. Except the boat is moving slow and the water is moving fast. Would put a lot of tension on the moon base end.

>> No.6265725

>>6265203
1) The Moon, while tidally locked, doesn't perfectly stay with one side precisely facing the Earth. It wobbles as it revolves around (look up Lunar Libration)

2) The Earth rotates faster than the Moon revolves

>> No.6265729

>>6265724

Oh, and it wouldn't work like a pendulum would it? The gravity will balance out at some point between the earth and moon. So the whole wire wouldn't experience the same force. One end will want to fall to the moon, the other will want to fall to Earth. The equilibrium will just want to chill out.

>> No.6265733

>>6265729
Actually I suppose in theory additional weights could be added onto the moon side of the cable to create more equilibrium

>> No.6267296

>>6265298
Your repetitiveness made me lol

>> No.6267752

>>6265203
How shall we bring the sun with us?

It looks as if the proposed idea is to use the moon to create a giant pendulum to swing us into space. Even if this would work life on earth requires the sun, and that is why this idiot idea will not work.

>> No.6267758

wires like this would only work if the moon was at a geostationary orbit (which it's not) and the earth-moon system were doubly tidally locked (that is, the same face of both bodies always faces each other.)

an elegant modification would be to put a ring around both bodies, and have the wire connected to carts that reside on tracks on the rings. these rings themselves would need to be able to change inclination with the moon's position, and likewise on the moon. point is, you try building a giant space ring that can tilt TWICE.

>> No.6269823

>>6265674
>expand
>contract
>wire.

>> No.6269971

>>6269823
that's not what he was saying at all.

>> No.6270068

>>6267752

>It looks as if the proposed idea is to use the moon to create a giant pendulum to swing us into space.

thats fucking retarded.

the best possible use for the rope, is transporting material from the moon to the earth for extremely cheap.

getting to the moon would still require conventional launches, but you could use the tether as a ladder or scaffold for small robots to climb along, taking metal ingots from the surface of the moon, to the earth's upper atmosphere, where their own lack of velocity will cause them to re-enter the atmosphere and land.

it would be extroardinarily energy efficient, it just wouldnt be very fast.

it would be a great way to transport ultra-valuable precious metals (like osmium, platinum, gold, iridium, etc) and lunar soil samples from the moon back to earth.

its a brilliant idea to anyone who can understand what it would actually be useful for.

>> No.6270071

>>6265234

pls post.

>> No.6270073

It wouldn't work for a number of reasons, but primarily because the Moon's orbit is not perfectly circular, as you seem to believe. Its distance from the Earth actually varies by about 150,000 km.

http://www.fourmilab.ch/earthview/pacalc.html

>> No.6270075

Doesn't the moon have like different distances or something?

>> No.6270077

>>6270068
You need to take a couple of introductory physics courses. It would take a ton of fucking energy to have the robots "climb" the rope.

A large part of the distance from the moon to the earth doesn't require much energy to move at all, because an object in motion tends to stay in motion, the only energy we need is to escape the earth and moon's gravity. Given these facts, the functional use of this rope would be utterly retarded.

Furthermore, given complexities in just our atmosphere, not to mention the moon's and deep space complexity concerning shit I have no idea about like gamma rays, this wire's movement would be completely fucking unpredictable. You talk about airplanes avoiding other airplanes, that's because we have a guidance system and plan those fucking routes. You can't just avoid a fucking goose in an airplane, you hit it. A wire flying through the fucking air at a moment's notice would be very hard to avoid.

I would call you an idiot, but you said you made it in a drunken stupor. Read up a bit on physics, and try to come up with better ideas, though!

>> No.6270081

the cable could work as a ladder for transporting materials from the lunar surface, to earthbound trajectories. all it needs to do is have an end close enough to the earth's surface that objects released will end up on a proper re-entry trajectory where they wont burn up.

this would reduce the cost of transporting materials from the moon to the earth, to levels where robotic mining of the moon may become profitable.

>> No.6270085

>>6270081
You would need the same amount of energy, actually more, to transport something via a cable. You're thinking of power, and yes with this you would not need as much power to leave the earth and could leave it a lot slower. The gravity well still exists on earth and the moon despite this wire though, and considering the friction of the wire to whatever fucking robot would carry it, it would actually take more energy to get to the moon, so it wouldn't reduce costs...

>> No.6270087

>>6270077

>It would take a ton of fucking energy to have the robots "climb" the rope.

yes, but the energy could be provided by solar panels, and the robots could take dozens, potentially even hundreds of loads before needing to be replaced. it wouldnt be free, but it would certainly be cheaper than current methods of taking things from the lunar surface back to earth.

the biggest expense is getting mass from the earth's surface, into lunar orbit, and re-usable vehicles for transport from the lunar surface to earth re-entry trajectories, would dramatically reduce the amount of mass that needs to leave the earth's surface.

>Furthermore, given complexities in just our atmosphere, not to mention the moon's and deep space complexity concerning shit I have no idea about like gamma rays, this wire's movement would be completely fucking unpredictable. You talk about airplanes avoiding other airplanes, that's because we have a guidance system and plan those fucking routes. You can't just avoid a fucking goose in an airplane, you hit it. A wire flying through the fucking air at a moment's notice would be very hard to avoid.

where did i say that the cable would hang in the atmosphere? it would only need to reach a distance close enough to allow released objects to re-enter the atmosphere without burning up. that would, at its closest, put the cable a few thousand kilometers away from the atmosphere.

>I would call you an idiot, but you said you made it in a drunken stupor. Read up a bit on physics, and try to come up with better ideas, though!

i'm not the OP.

>> No.6270090

>>6270085

more energy, yes. but less mass would need to be transported to the moon from the earth, in order to bring back a given mass from the lunar surface.

solar panels work great in space, and this is a way to use the energy from solar panels to take mass from the lunar surface, to earth re-entry trajectories, without needing expensive complex equipment that turns solar energy and water into rocketfuel.

it would probably take much, much more energy, but cost is the biggest factor, and if your energy is supplied by solar panels, using alot of energy is okay.

>> No.6270095

Moon's side from Earth's perspective stays the same, but
Earth revolves.

Cord will have to move with the speed of revolving.
Implausible.

NEXT IDEA

>> No.6270098

>>6270073

actually 49,600km deviation.

probably not the largest problem but a significant one.

>>6270095

doesn't matter where the cable 'ends' at the earth, long as its at the earth. read the post carefully.

>>6270085

the power consumption wouldn't matter if it was all provided by the sun for free. powering a robot to move via solar panels and robotic gears can be done entirely by electricity, with little to no investment from earth resources to do it.

honestly my biggest concern with the concept is that you'd have to build the thing. how would you construct it? fly a few hundred thousand km of cable up to the moon, then launch a small rocket pulling the wire behind it in retrograde so it falls away from the moon and slowly puts it far enough past the lagrangian point so that it doesn't fall back down?
seems like an absurd engineering challenge.

>> No.6270111

>>6270068

transporting stuff from the moon to the earth is already very easy, its getting the launch vehicle to the moon that is costly.

creating a railgun on the moon to launch packages into an earth return trajectory could be accomplished with just electricity and wouldn't require a 360+ thousand km cable.

>> No.6270112

The moon rotates about itself. The wire ends up coiled around the moon in 908.3 days.

Assuming a wire diameter of 1m (and a lot of other things), we'd end up with a moon with an equatorial wall 33.24 meters in height.

Which is awesome.

>> No.6270113

>>6270112

that does sound awesome, but the moon rotating about 'itself' doesn't matter if the cable is within earths gravity well, as the face of the moon that is facing the earth stays the same, all the time, so it wouldn't wrap anything.

>> No.6270117

>>6270113
Unravel a ball of yarn, which is also within gravity's well, and rotate it about itself. You'll end up with a ball of yarn.

>> No.6270121

>>6270117

unravel a ball of yarn to a point, stick it up in the air, tie one end to another ball, and then spin it around counter clockwise at the same rate the other ball spins around counter clockwise.

its the same concept, it doesn't ravel or unravel.

>> No.6270125

>>6270117

relative to the earth's gravity well, the moon does not rotate.

the cable and the cable's anchor on the moons surface would always point towards the earth.

>> No.6270145

>>6270112
>never once in life realize that moon does not rotate with respect to earth's surface

wow you are astonishingly retarded, even for /sci

>> No.6270156
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6270156

Ad elipticity of moon orbit
:
It should suffice to make the cable as long as the closest point to earth. The platform whould only be accessible twice every month. Also it whould be accessible at shifting positions.

On the other hand, this would ged rid of most of the sheering.

>> No.6270175

>>6270121
I just did. Took me a while to find them.

It ravels.

>> No.6270185

>>6270175

then you fucked it up quite thoroughly and are missing the concept entirely.

the moon is tidally locked to the earth. it rotates, but the same face is always facing at the earth.

if the cable is extended from the moon, towards the earth, far enough that enough of it is within its gravity well, it won't ravel up around the moon, as the earth is holding it in place.

you can't really simulate gravity wells with balls of yarn, you have to attach the end of the string to the other ball. do one full rotation, counter clockwise, with the extending ball at the same rate you do a full rotation, also counter clockwise, with the ball you attach the string to. hold each of them above the ground/table whatever.