Space elevator

[Day]

Hello everybody,

I'm currently working on the incentives to launch an attack / war in the Diplomacy Oxp. Economy should play a role (war economy increases the GDP; battle destruction lowers GDP).

So I had to think on the economic ties between planetary systems.

It seems to me that:
- either space elevators exist in the Ooniverse, and economic ties may be significant,
- or space elevators do not exist in the Ooniverse, and economic ties are tenuous due to the prohibitive cost of planet-station goods delivery. It might even be that galactic expansion could not happen without space elevators.

What do you think?

Do space elevators exist in the Ooniverse?

And ps: somebody to model a space elevator?

[Disembodied]

- either space elevators exist in the Ooniverse, and economic ties may be significant,
- or space elevators do not exist in the Ooniverse, and economic ties are tenuous due to the prohibitive cost of planet-station goods delivery. It might even be that galactic expansion could not happen without space elevators.

There's a third option: there are no space elevators, but economic ties are still significant, because planet–station deliveries aren't expensive thanks to cheap antigravity. We know that shuttles and transporters travel from planet to station and back without the need for chemical rockets and the expenditure of vast amounts of fuel, and that Adders and Morays are both fitted for planetary descent. Building a space elevator might be seen as prohibitively expensive, for the benefits it might provide - like building a transatlantic bridge. Plus, it would create a point of extreme vulnerability, and potential planetary catastrophe if it ever fell.

You might still get space elevators in some planets - maybe ones that have very large imports/exports of bulk goods, making it economic. Or maybe around certain low-g moons, to facilitate strip-mining?

[Day]

There's a third option: there are no space elevators, but economic ties are still significant, because planet–station deliveries aren't expensive thanks to cheap antigravity. We know that shuttles and transporters travel from planet to station and back without the need for chemical rockets and the expenditure of vast amounts of fuel, and that Adders and Morays are both fitted for planetary descent.

Cheap antigravity.
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.
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Ok.
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Good idea. Powered externally by quirium. I like it

[Malacandra]

We know that ships' drives (normal space - not Witchdrive) can run indefinitely without refuelling. If you have that then you can lift payloads into orbit for essentially nothing, and you don't even have to hit orbital velocity to get into space. (explanation on request ). As long as you have that then you don't need a space elevator because your cargo hauler can crawl its way up just as well without a cable to pull itself along by.

But we should have a Space Elevators OXZ anyway, because Rule of Cool.

[Day]

We know that ships' drives (normal space - not Witchdrive) can run indefinitely without refuelling.

I assumed it was because no gravity + no friction implies eternal travel?
Energy would only be needed to steer.

But we should have a Space Elevators OXZ anyway, because Rule of Cool.

[Malacandra]

We know that ships' drives (normal space - not Witchdrive) can run indefinitely without refuelling.

I assumed it was because no gravity + no friction implies eternal travel?
Energy would only be needed to steer.

No, space doesn't work like that - there is gravity as long as you're anywhere near a planet or a star, which heavily restricts how real spacecraft behave, and also, a rocket's fuel is a huge component of its mass and most of a Saturn V's take-off weight was fuel + somewhere to put it. In order to leave Earth orbit and head for the Moon you had to crank it up to 25,000 mph, but you were bleeding off speed every inch of the way up to the Moon (barring the last thousand miles or so where the Moon's gravity finally took over) which is why it took about three days to cover 248,000 miles instead of less than ten hours.

Elsewhere in the solar system, you will keep travelling in a straight line indefinitely - except, as Einstein tells us, it'll be a straight line in curved space. To us mere mortals that looks a lot more like an ellipse, and you won't leave the solar system or even reach a radically different planet without a lot of power input or, more practically for our space probes, a gravity slingshot whereby we can siphon off an insignificant amount of a planet's orbital velocity and give it to the probe. Fun fact: it's easier to reach Pluto than the Sun; that's counterintuitive but perfectly true.

As you can see, physics in the OoVerse works differently. Whatever speed you want to be doing, you need a certain power output, implying that OoSpace isn't frictionless (except, as you can see, for cargo barrels, which bat along at whatever speed they were dropped at). Also, rotational momentum isn't conserved either. From what I remember from about 1985, you had the option in Elite to conserve momentum and rotation... and it was darned hard to fly a ship that way.

Whatever speed you're doing, your drive is at a certain setting, and you can see the evidence from an external view. But you could fly for ever without running your drive fuel out, for all the game says otherwise, and since your ship doesn't change mass while all this is going on, it's much easier to get a drive-equipped ship (such as an Adder or a Moray) from surface to orbit: just stand the ship on its tail and, as long as you can go up at all in a vertical climb, you can reach space. (The narrator of the Sidewinder series comments on this from time to time.)

And once again, yeah, space elevators.

[Day]

No, space doesn't work like that - there is gravity as long as you're anywhere near a planet or a star, which heavily restricts how real spacecraft behave, and also, a rocket's fuel is a huge component of its mass and most of a Saturn V's take-off weight was fuel + somewhere to put it. In order to leave Earth orbit and head for the Moon you had to crank it up to 25,000 mph, but you were bleeding off speed every inch of the way up to the Moon (barring the last thousand miles or so where the Moon's gravity finally took over) which is why it took about three days to cover 248,000 miles instead of less than ten hours.

Elsewhere in the solar system, you will keep travelling in a straight line indefinitely - except, as Einstein tells us, it'll be a straight line in curved space. To us mere mortals that looks a lot more like an ellipse, and you won't leave the solar system or even reach a radically different planet without a lot of power input or, more practically for our space probes, a gravity slingshot whereby we can siphon off an insignificant amount of a planet's orbital velocity and give it to the probe. Fun fact: it's easier to reach Pluto than the Sun; that's counterintuitive but perfectly true.

I'm totally ok with all of this

As you can see, physics in the OoVerse works differently. Whatever speed you want to be doing, you need a certain power output, implying that OoSpace isn't frictionless (except, as you can see, for cargo barrels, which bat along at whatever speed they were dropped at). Also, rotational momentum isn't conserved either. From what I remember from about 1985, you had the option in Elite to conserve momentum and rotation... and it was darned hard to fly a ship that way.

Whatever speed you're doing, your drive is at a certain setting, and you can see the evidence from an external view. But you could fly for ever without running your drive fuel out, for all the game says otherwise, and since your ship doesn't change mass while all this is going on, it's much easier to get a drive-equipped ship (such as an Adder or a Moray) from surface to orbit: just stand the ship on its tail and, as long as you can go up at all in a vertical climb, you can reach space. (The narrator of the Sidewinder series comments on this from time to time.)

Welllll... I like to think that the Ooniverse has the same physical laws as our own, that the fuel is needed to counterbalance the gravity / steer, that the controls are this way because they go through a pilot interface and this way lets gravity-evolved sentient beings pilot high-risk ships, and finally that the exhaust lights we see are an help for other pilots (like our orange car steering lights).

Of course, why would fighting ships exhibit these helpful exhaust lights ?
Nothing's perfect.

[Diziet Sma]

No, space doesn't work like that - there is gravity as long as you're anywhere near a planet or a star, which heavily restricts how real spacecraft behave, and also, a rocket's fuel is a huge component of its mass and most of a Saturn V's take-off weight was fuel + somewhere to put it. In order to leave Earth orbit and head for the Moon you had to crank it up to 25,000 mph, but you were bleeding off speed every inch of the way up to the Moon (barring the last thousand miles or so where the Moon's gravity finally took over) which is why it took about three days to cover 248,000 miles instead of less than ten hours.

Correct, so far...

Elsewhere in the solar system, you will keep travelling in a straight line indefinitely

And here you went off the rails.. no matter where you are in the solar system, you're in orbit around something, usually the sun. And all the restrictions you mentioned above still apply. This is why my childhood idea of simply shooting nuclear waste into the sun to dispose of it won't work. To get into orbit around Earth requires some 8-9.5 km/s of delta-v (delta-v means "change in velocity"). Once in orbit around the Earth, you have to expend more yet energy (a further 3.2-1.7 km/s - for a total from liftoff of 11.2 km/s) to escape Earth's gravity well. Once you've done that, you're now orbiting the sun at almost (+/- a bit, depending on what direction you went) the same speed as the Earth. To impact the sun's "surface", you now need to cancel out the speed of that movement around the sun, which requires another 30 km/s of thrusting against the direction of rotation.

In short, my childish fantasy would be horrendously expensive. It's probably not possible to build a rocket big enough to do such a thing. It would utterly dwarf Von Braun's Sea Dragon.

There are no "straight lines" in space.. you're ALWAYS in orbit around something, even if it's galactic centre.

[Malacandra]

No, space doesn't work like that - there is gravity as long as you're anywhere near a planet or a star, which heavily restricts how real spacecraft behave, and also, a rocket's fuel is a huge component of its mass and most of a Saturn V's take-off weight was fuel + somewhere to put it. In order to leave Earth orbit and head for the Moon you had to crank it up to 25,000 mph, but you were bleeding off speed every inch of the way up to the Moon (barring the last thousand miles or so where the Moon's gravity finally took over) which is why it took about three days to cover 248,000 miles instead of less than ten hours.

Correct, so far...

Elsewhere in the solar system, you will keep travelling in a straight line indefinitely

And here you went off the rails.. no matter where you are in the solar system, you're in orbit around something, usually the sun. And all the restrictions you mentioned above still apply. This is why my childhood idea of simply shooting nuclear waste into the sun to dispose of it won't work. To get into orbit around Earth requires some 8-9.5 km/s of delta-v (delta-v means "change in velocity"). Once in orbit around the Earth, you have to expend more yet energy (a further 3.2-1.7 km/s - for a total from liftoff of 11.2 km/s) to escape Earth's gravity well. Once you've done that, you're now orbiting the sun at almost (+/- a bit, depending on what direction you went) the same speed as the Earth. To impact the sun's "surface", you now need to cancel out the speed of that movement around the sun, which requires another 30 km/s of thrusting against the direction of rotation.

In short, my childish fantasy would be horrendously expensive. It's probably not possible to build a rocket big enough to do such a thing. It would utterly dwarf Von Braun's Sea Dragon.

There are no "straight lines" in space.. you're ALWAYS in orbit around something, even if it's galactic centre.

Bolding mine...

And if you hadn't stopped mid-sentence, you'd have noticed that I continued:

except, as Einstein tells us, it'll be a straight line in curved space.

The rest of your post is, of course, spot on.

EDIT: I never heard of the Sea Dragon before. Horizons broadened - thank you!