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Jupiter is deep

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Re: Jupiter is deep

#71

Post by sliken »

Simon_says wrote: post #45
josu wrote: post #32

Earlier quoted context omitted.

>And probably a month of airplane travel just to get there. Space travel would probably be more advanced by now.

It would be drastically harder to get out of the gravity well on the planet. Even if the strength of gravity at the surface was the same as Earth’s, the field would be stronger farther out than Earth’s —- 11x as much due to the geometry. It would take 11x more energy to escape the planet, though low orbit would be practically the same difficulty.

Escape velocity is 6x the earths, 60km/sec or so.

Re: Jupiter is deep

#72

Post by Simon_says »

sliken wrote: post #71
Simon_says wrote: post #45

Earlier quoted context omitted.

It would be drastically harder to get out of the gravity well on the planet. Even if the strength of gravity at the surface was the same as Earth’s, the field would be stronger farther out than Earth’s —- 11x as much due to the geometry. It would take 11x more energy to escape the planet, though low orbit would be practically the same difficulty.

Escape velocity is 6x the earths, 60km/sec or so.

That's Jupiter. We're talking about a hypothetical planet of Jupiter's size and Earth's surface gravity.

Re: Jupiter is deep

#73

Post by Simon_says »

Armisael16 wrote: post #62
Simon_says wrote: post #45

Earlier quoted context omitted.

It would be drastically harder to get out of the gravity well on the planet. Even if the strength of gravity at the surface was the same as Earth’s, the field would be stronger farther out than Earth’s —- 11x as much due to the geometry. It would take 11x more energy to escape the planet, though low orbit would be practically the same difficulty.

Low orbit would also be a lot more difficult; when you scale a planet's radius and mass to preserve surface gravity, all delta-v requirements scale as the square root of the of radius.

Oh, yea, you're right.

Re: Jupiter is deep

#74

Post by tempestn »

sliken wrote: post #70
tempestn wrote: post #44

Earlier quoted context omitted.

I wonder if it would be possible for such a planet to exist and be habitable. Obviously it would have to be far less dense than Earth (or Jupiter); I'm guessing gravity would therefore compact it to a smaller size, unless maybe it was made out of some kind of lattice structure? Better question might be what's the largest feasible (or likely) potentially habitable planet with earth-like gravity.

Mass of Saturn is 100x earth and the gravity is only 6% higher.

But not with a solid surface at that size.

Re: Jupiter is deep

#75

Post by v_lisivka »

rocqua wrote: post #67
v_lisivka wrote: post #56

> There's a single Southern Polar Cyclone (the SPC in this case), but only five cyclones around it! They're bigger too, and are different sizes, ranging from 5,600 to 7,000 km across. Again, it's not clear why the poles are different. The fact that there are fewer in the south and they're bigger may be related (I'm guessing, but if you have fewer they can grow to fill more space … ?), but no one really knows. Maybe b…

That would mean 7 southern cyclones accounted for. This is still different from the 9 on the northern pole.

Maybe because central cyclone merged 2 side cyclones, so it has extra energy to escape South pole.

Re: Jupiter is deep

#76

Post by konart »

cup-of-tea wrote: post #68
konart wrote: post #63

Earlier quoted context omitted.

Not a specialist here, but bigger distances will mean - more time to discover other places and other people which means you won't find new knowledge for some time and then you will need more time to bring it to your people. Slower trade too.

But it doesn't imply resources are more spread out. The only thing a smaller planet means is that your civilisation will more quickly be able to circumnavigate it, but that doesn't seem relevant at all.

>But it doesn't imply resources are more spread out

No, but what the point of resources if you don't know how to use them? For example - paper. China had it for more than a thousand of years before it reached Europe. Papermaking gave a great boost to our civilization, but imagine our world with papermaking just being introduced to the middle east.

Re: Jupiter is deep

#77

Post by zhte415 »

cup-of-tea wrote: post #58
zhte415 wrote: post #46

Earlier quoted context omitted.

Assuming the existance of something like early human hunter-gatherers, if the earth were the size of Jupiter, we would not have transitioned to living in cities yet. There would be no downloading.

Why not? Why does a bigger planet mean slower progress?

Less population density means less specialism. Higher population density allows the ability for some of the population to have the ability specialise (and by mixing with others in the same or allied specialisations in higher and higher populations, can allow increased returns to scale of what the individual is already specialised in).
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