3 ms·

If you've solved the energy problem of accelerating most of a human colony and its gear to interstellar object speeds, do you really get much from trying to hit

by pvg 4y ago

If you've solved the energy problem of accelerating most of a human colony and its gear to interstellar object speeds, do you really get much from trying to hitch a ride on such an object? You've also presumably solved energy storage so the time spent waiting for a suitable object you might as well spend on storing energy to accelerate an object at hand.

andyjohnson0 4y ago
Good point. The only advantage that occurs to me is that you could spend the journey (waves hands) converting the interstellar object into reaction mass to enable deceleration at the other end. And maybe also for course correction, because the object is very pretty unlikely to be going anywhere interesting just by chance
- pvg 4y ago
  I typed slapdash things into Wolfram Alfa just to get a sense of the kinetic energy of something like a 100km metal sphere buzzing as at 40 km/s (it's a screaming chonker of an overestimate but hey) and got something like a millionth of total yearly solar output or 1/5th of lunar kinetic energy (orbiting earth). As D. Wooderson famously said, we're talkin' some fuckin' muscle, to ride such a thing. If you have it, you might even be better off just taking the moon instead.
cletus 4y ago
So for a colony to last centuries in interstellar space with little to no prospect of resupply of any kind, you have to build in an awful lot of redundancy. You also need to cater for growth. You need a lot of infrastructure for long term care (eg hospitals). What you're building is living quarters for a thousand years over multiple generations. But for a rogue planet you need far less. Consider the Moon. It has lava tubes. You can seal these, fill them with air and live in them. You don't need to accelerate that living space. Sure you still need to bring some things but it's far, far less. What's more, if you have several such settlements in different lava tubes you have automatic redundancy. A single catastrophe won't snuff out the entire colony. So for a true interstellar colony you really have to build a fleet because a single colony is too big of a failure mode.
- johnchristopher 4y ago
  > Consider the Moon. It has lava tubes. You can seal these, fill them with air and live in them. Theses are called Paulis's mines.
- pvg 4y ago
  Yeah my point is that with the energy tech implied, you might just be able to take a moon or the Moon instead. https://news.ycombinator.com/item?id=31534464 https://news.ycombinator.com/item?id=31534464
- q1w2 4y ago
  A colony of fleshy biological creatures in an unsuspended form? This seems silly. Even if intelligence remains biological (which I find exceedingly unlikely), then why wouldn't you just freeze them? That's a lot easier than moving a PLANET. FYI - rodents can be frozen and revived. There's no fundamental reason you cannot freeze and thaw a human.

by pvg 4y ago

andyjohnson0 4y ago

Good point. The only advantage that occurs to me is that you could spend the journey (waves hands) converting the interstellar object into reaction mass to enable deceleration at the other end. And maybe also for course correction, because the object is very pretty unlikely to be going anywhere interesting just by chance

pvg 4y ago
I typed slapdash things into Wolfram Alfa just to get a sense of the kinetic energy of something like a 100km metal sphere buzzing as at 40 km/s (it's a screaming chonker of an overestimate but hey) and got something like a millionth of total yearly solar output or 1/5th of lunar kinetic energy (orbiting earth). As D. Wooderson famously said, we're talkin' some fuckin' muscle, to ride such a thing. If you have it, you might even be better off just taking the moon instead.

cletus 4y ago

So for a colony to last centuries in interstellar space with little to no prospect of resupply of any kind, you have to build in an awful lot of redundancy. You also need to cater for growth. You need a lot of infrastructure for long term care (eg hospitals). What you're building is living quarters for a thousand years over multiple generations. But for a rogue planet you need far less. Consider the Moon. It has lava tubes. You can seal these, fill them with air and live in them. You don't need to accelerate that living space. Sure you still need to bring some things but it's far, far less. What's more, if you have several such settlements in different lava tubes you have automatic redundancy. A single catastrophe won't snuff out the entire colony. So for a true interstellar colony you really have to build a fleet because a single colony is too big of a failure mode.

johnchristopher 4y ago
> Consider the Moon. It has lava tubes. You can seal these, fill them with air and live in them. Theses are called Paulis's mines.
pvg 4y ago
Yeah my point is that with the energy tech implied, you might just be able to take a moon or the Moon instead. https://news.ycombinator.com/item?id=31534464 https://news.ycombinator.com/item?id=31534464
q1w2 4y ago
A colony of fleshy biological creatures in an unsuspended form? This seems silly. Even if intelligence remains biological (which I find exceedingly unlikely), then why wouldn't you just freeze them? That's a lot easier than moving a PLANET. FYI - rodents can be frozen and revived. There's no fundamental reason you cannot freeze and thaw a human.