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Sometimes I wonder how different our world might be if it were the size of Jupiter but at the surface still had the same gravity we have now. It could take day

Sometimes I wonder how different our world might be if it were the size of Jupiter but at the surface still had the same gravity we have now. It could take days to download something from the other side of the planet. And probably a month of airplane travel just to get there.

new299 9y ago
Latency would be higher, and might make phone calls a little awkward perhaps?, but it shouldn't make any longer to download a file. You might want to modify protocols so they send acknowledgements less often, or use larger packets perhaps.
- Godel_unicode 9y ago
  Exactly this. It's always amazing to me how latency gets confused with bandwidth.
- matte_black 9y ago
  Ah yea, I guess you’re right. With a small planet it’s something I never have to think much about since things always seem fast enough.
josu 9y ago
>And probably a month of airplane travel just to get there. Space travel would probably be more advanced by now.
- Simon_says 9y ago
  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.
  - Armisael16 9y ago
    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.
    - Simon_says 9y ago
      Oh, yea, you're right.
  - sliken 9y ago
    Escape velocity is 6x the earths, 60km/sec or so.
    - Simon_says 9y ago
      That's Jupiter. We're talking about a hypothetical planet of Jupiter's size and Earth's surface gravity.
aaron695 9y ago
This is Cunningham's Law's at it's best. Jupiter/Circumference 439,264 km Earth is 40,075 km It's only 10 times different. Streaming would be pretty much the same, 10 times the lag would cause some issues but not much really. Travel is more interesting. Earth is around one day flying to anywhere. So 10 days. This assumes the airline industry can support enough hubs, the population would be much thinner. And here it gets confusing since would people all just live where it's warm around the equator since there's so much room and resources? What's a day here? Would airships be more popular cause the winds up top I'd assume would be blowing pretty fast. Would airlines be more expensive per kilometer. Since the population is sparse and 10 times as far between major interesting places maybe it's not as viable. Would you spend 10 days going to London knowing it's still a days flight to Paris.
tempestn 9y ago
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.
- cup-of-tea 9y ago
  That's an interesting question. I'm sure it's been considered in science-fiction before. But as I think about I keep thinking about a hollow planet, and then I think about a Dyson sphere. Does that count as a planet?
- sliken 9y ago
  Mass of Saturn is 100x earth and the gravity is only 6% higher.
  - tempestn 9y ago
    But not with a solid surface at that size.
zhte415 9y ago
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.
- cup-of-tea 9y ago
  Why not? Why does a bigger planet mean slower progress?
  - konart 9y ago
    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.
    - cup-of-tea 9y ago
      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.
      - konart 9y ago
        >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.
  - zhte415 9y ago
    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).
drewg123 9y ago
You should read Robert Silverberg's Majipoor series. It is a fantasy series about a planet that's much larger than earth, but less dense. https://en.wikipedia.org/wiki/Majipoor_series https://en.wikipedia.org/wiki/Majipoor_series

new299 9y ago

Latency would be higher, and might make phone calls a little awkward perhaps?, but it shouldn't make any longer to download a file. You might want to modify protocols so they send acknowledgements less often, or use larger packets perhaps.

Godel_unicode 9y ago
Exactly this. It's always amazing to me how latency gets confused with bandwidth.
matte_black 9y ago
Ah yea, I guess you’re right. With a small planet it’s something I never have to think much about since things always seem fast enough.

josu 9y ago

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

Simon_says 9y ago
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.
- Armisael16 9y ago
  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.
  - Simon_says 9y ago
    Oh, yea, you're right.
- sliken 9y ago
  Escape velocity is 6x the earths, 60km/sec or so.
  - Simon_says 9y ago
    That's Jupiter. We're talking about a hypothetical planet of Jupiter's size and Earth's surface gravity.

aaron695 9y ago

This is Cunningham's Law's at it's best. Jupiter/Circumference 439,264 km Earth is 40,075 km It's only 10 times different. Streaming would be pretty much the same, 10 times the lag would cause some issues but not much really. Travel is more interesting. Earth is around one day flying to anywhere. So 10 days. This assumes the airline industry can support enough hubs, the population would be much thinner. And here it gets confusing since would people all just live where it's warm around the equator since there's so much room and resources? What's a day here? Would airships be more popular cause the winds up top I'd assume would be blowing pretty fast. Would airlines be more expensive per kilometer. Since the population is sparse and 10 times as far between major interesting places maybe it's not as viable. Would you spend 10 days going to London knowing it's still a days flight to Paris.

tempestn 9y ago

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.

cup-of-tea 9y ago
That's an interesting question. I'm sure it's been considered in science-fiction before. But as I think about I keep thinking about a hollow planet, and then I think about a Dyson sphere. Does that count as a planet?
sliken 9y ago
Mass of Saturn is 100x earth and the gravity is only 6% higher.
- tempestn 9y ago
  But not with a solid surface at that size.

zhte415 9y ago

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.

cup-of-tea 9y ago
Why not? Why does a bigger planet mean slower progress?
- konart 9y ago
  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.
  - cup-of-tea 9y ago
    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.
    - konart 9y ago
      >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.
- zhte415 9y ago
  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).

drewg123 9y ago

You should read Robert Silverberg's Majipoor series. It is a fantasy series about a planet that's much larger than earth, but less dense. https://en.wikipedia.org/wiki/Majipoor_series https://en.wikipedia.org/wiki/Majipoor_series