Re: What would be the most significant thing to happen if a rope (or wire) tied the Earth and the Moon together?
by syphilis (Archbishop) on Nov 02, 2015 at 02:59 UTC
|
This is ridiculous - how are you going to properly secure a rope to a lump of cheese ??
Cheers,
Rob | [reply] [Watch: Dir/Any] |
|
| [reply] [Watch: Dir/Any] |
|
how are you going to properly secure a rope to a lump of cheese
You'll make a quantum leap in understanding the whole idea if you picture the moon in your mind as Swiss cheese.
Through the moon Alice, through the moon!
| [reply] [Watch: Dir/Any] |
|
| [reply] [Watch: Dir/Any] |
Re: What would be the most significant thing to happen if a rope (or wire) tied the Earth and the Moon together?
by BrowserUk (Patriarch) on Nov 01, 2015 at 17:55 UTC
|
Given the Moon's mass is 7.3477×1022; and a "cable" made of carbon nanotubes with a tensile strength of 63 gigapascals would need to have a diameter of 4000km in order to endure the tension of that mass -- and that's ignoring the mass of the cable itself ~185 trillion tonnes -- I'll wait until someone works out how to manufacture the 4000km diameter x 400000km cable and finds a source of energy on earth sufficient to lift it into space before I start worrying about the consequences of doing this :)
With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
In the absence of evidence, opinion is indistinguishable from prejudice.
| [reply] [Watch: Dir/Any] |
|
The problem is not holding up the moon but stopping it... well, I mean, the main problem!
| [reply] [Watch: Dir/Any] |
|
The problem is not holding up the moon but stopping it...
"Tension" is holding it back; not holding it up.
Actually you'd have to speed the moon up (or slow the Earth down) since the former rotates every 27 days but the latter rotates once a day.
And if you sped the moon up to match the Earth's rotational speed, then the tension on the cable would be hugely increased necessitating a further increase in its diameter.
With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
In the absence of evidence, opinion is indistinguishable from prejudice.
| [reply] [Watch: Dir/Any] |
|
Yes. Once we get the moon to be stable above one point of the earth, there would be (nearly) no force on the rope, and we might get the effect of a Space Elevator.
But the difficulty would be to get the moon into a suitable position, so it could serve as a counterwight.
This would probably lead to a lot of changes on earth, e.g related to the tides. Or to Astrology. But I'd like to focus on the opportunities, e.g rope-climbing-competitions ;-)
| [reply] [Watch: Dir/Any] |
|
|
|
The Moon and the Earth are already roped together—gravitationally. And we know what that means.
I gather the question is if another, physical tether were attached to both. It'd most likely have a healthy amount of slack to account for the elliptical orbit. Perhaps a counterweight is in order at some intermediate point to provide tension. In any case, the rope would have to endure its own weight only (which is still quite a task!), plus some for doing useful work.
| [reply] [Watch: Dir/Any] |
|
Mass and force are not the same.
F = m * a
Isaac Newton
| [reply] [Watch: Dir/Any] |
|
| [reply] [Watch: Dir/Any] |
Re: What would be the most significant thing to happen if a rope (or wire) tied the Earth and the Moon together?
by shmem (Chancellor) on Nov 01, 2015 at 17:19 UTC
|
The rope would get up and down in pitch in the cosmic wind - depending on length and tension - as the moon travels from perihelion to aphelion and back.
(update: to make that audible, the sound must be transposed by many octaves higher - unless a spaceship of significant mass silences the chord at an overtone node.)
perl -le'print map{pack c,($-++?1:13)+ord}split//,ESEL'
| [reply] [Watch: Dir/Any] |
Re: What would be the most significant thing to happen if a rope (or wire) tied the Earth and the Moon together?
by LanX (Saint) on Nov 01, 2015 at 17:00 UTC
|
depends ... where exactly on moon and earth would you try to anchor the "rope"?
| [reply] [Watch: Dir/Any] |
|
| [reply] [Watch: Dir/Any] |
|
Let's suppose we have a rope with more than 10% elasticity (relative delta of distance)
The earth is always visible from the near side of the moon (that's the other half from what people erroneously call the "dark" side).
If the moon was always visible from one of the poles (like the sun is for almost half a year) you'd only need to compensate approximately 360°/24h (the moons orbital rotation of 360°/month doesn't matter much) with something like a slowly rotating swivel.
But that's never the case, I suppose the moon is at best only visible for 18 days in a row IIRC.
So you'd end up constructing a large tower in Antarctica, such that from top the moon is always over the horizon.
No idea how tall this tower must be, but if it crosses the atmosphere (I'm pretty sure it must¹) this would also solve the problem of a giant whip lashing thru air.
All the construction problems aside, I wouldn't be surprised about electrostatic problems arising from connecting two giant bodies.
Can't see the benefit of such a construction, that's at best a theoretical question for math class.
PS: pollsters seem to be desperate. ;-)
¹) too lazy for calculations, but alone with an ecliptic angle of 23° something like 1-3 thousand km would be "reasonable".
update
Quick calculation say a tower on the pole needs roughly 1000km height (at least) to be able to see the moon all year from the tip. (6371/cos 30° = 7356 )
Well that's already 3 times higher than the ISS orbit...
| [reply] [Watch: Dir/Any] |
|
|
|
|
|
|
where exactly on moon and earth would you try to anchor the "rope"?
It's times like these that we appreciate having decades of videos to show us the answer to all our problems:
For the Earth, you can attach it to the same spot Superman used to push the entire Earth. It's so amazing that even Batman challenged the idea.
| [reply] [Watch: Dir/Any] |
|
| [reply] [Watch: Dir/Any] |
Re: What would be the most significant thing to happen if a rope (or wire) tied the Earth and the Moon together?
by GotToBTru (Prior) on Nov 13, 2015 at 16:46 UTC
|
The one thing in favor of this scheme is the unequal distribution of mass in the Moon keeps one side always facing the Earth. But it does not stay over the same point on the Earth, so a physical connection would not be possible or even desirable.
The solution is to anchor a rope to the surface of the Moon, but cut it a few feet short of the distance to the Earth's surface. The Earth end of the rope can move freely as the Moon orbits. Then, when you want to get to the Moon without a rocket, you just need to grab the end of the rope as it goes by.
| [reply] [Watch: Dir/Any] |
|
Better yet. Attach it this end and leave the other end floating.
That way you have a 27 day cycle in which to send things up the rope and they simply queue at the other end until the Moon comes around.
You could even have multiple Earth-fixed cables; thus avoiding Earth-bound shipping costs of the Moon-bound cargo.
I love queues! (After all, I'm English :)
With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
In the absence of evidence, opinion is indistinguishable from prejudice.
| [reply] [Watch: Dir/Any] |
|
| [reply] [Watch: Dir/Any] |
|
How long would that rope need to be in order to not just fall back down to earth? I.E. the crossing point between gravity and centripetal force
| [reply] [Watch: Dir/Any] |
|
|
Re: What would be the most significant thing to happen if a rope (or wire) tied the Earth and the Moon together?
by FloydATC (Deacon) on Nov 13, 2015 at 10:03 UTC
|
It's hard to pick just one... Cheese manufacturers would go bankrupt because cheese would now be free. General interest in rope and rope technology would get a significant boost. Conspiracy theorists would claim that the earth and moon have not actually been tied together, it's all a lie. Religious groups would find new and interesting reasons to harass and kill innocent people, especially those who supports the idea of tethering the earth and moon together because various religious texts clearly warn that this heralds the end of times. Several people would try to climb the rope and get themself killed in new and hilarious ways (not limited to fatal rope burns). An unprecedented amount of lawsuits would ensue.
-- FloydATC
Time flies when you don't know what you're doing
| [reply] [Watch: Dir/Any] |
Re: What would be the most significant thing to happen if a rope (or wire) tied the Earth and the Moon together?
by LanX (Saint) on Nov 15, 2015 at 13:31 UTC
|
| [reply] [Watch: Dir/Any] |
Re: What would be the most significant thing to happen if a rope (or wire) tied the Earth and the Moon together?
by karlgoethebier (Abbot) on Nov 10, 2015 at 12:27 UTC
|
After reading the previous posts i must admit that i wasn't aware that they legalized weed in the monastry.
BTW, i want those golf balls back ;-)
Regards, Karl
«The Crux of the Biscuit is the Apostrophe»
| [reply] [Watch: Dir/Any] |
|
i wasn't aware that they legalized weed
With people hacking away at their keyboards, who'd notice anyway?
| [reply] [Watch: Dir/Any] |
Re: What would be the most significant thing to happen if a rope (or wire) tied the Earth and the Moon together?
by chacham (Prior) on Nov 13, 2015 at 15:49 UTC
|
| [reply] [Watch: Dir/Any] |
|
| [reply] [Watch: Dir/Any] |
|
| [reply] [Watch: Dir/Any] |
Re: What would be the most significant thing to happen if a rope (or wire) tied the Earth and the Moon together?
by Anonymous Monk on Nov 30, 2015 at 16:00 UTC
|
The rope or wire would break, no matter how strong it was
The wording of this option has us assume the cable can be infinitely strong, thus removing it as an option. | [reply] [Watch: Dir/Any] |