31–40 of 55 posts
What better intergalactic colony ship than a whole star system accelerated to a significant fraction of c.
But how can a civilization even start to move a star to a degree it fills a purpose?
Earlier quoted context omitted.
You underestimate the emptiness of space.
We had a "close" flyby (0.82 lightyears) about 70,000 years ago! https://en.wikipedia.org/wiki/Scholz%27s_Star
Can these very fast stars bump into another solar system? Probably very unlikely, but is it possible?
Possible yes, likely, no. An example, the collision of the Milky Way with Andromeda is likely to produce no collisions of solar systems. Space is big.
I was curious about this, so I found this source[0] via wikipedia:
"Although the galaxies will plow into each other, stars inside each galaxy are so far apart that they will not collide with other stars during the encounter. However, the stars will be thrown into different orbits around the new galactic center. Simulations show that our solar system will probably be tossed much farther from the galactic core than it is today."
Interpreted literally, it would seem this at least leaves open the idea that a star passing through any other star's solar system and, say, sending its planets into wildly different orbits or flinging some into interstellar space, is meaningfully more likely than a star actually physically hitting another star, but I haven't seen the math. I wouldn't be surprised if they're both extremely unlikely - the diameter of our solar system appears to be about 8500 times larger than the diameter of the sun, which may not change the odds in any significant way.
[0] https://www.nasa.gov/mission_pages/hubble/science/milky-way-...
Isaac Arhur touches on this subject in one of his videos, Intergalactic Colonization [1]. Basically, the void between galaxies isn't actually that much of a void. It's just in intergalactic space stars tend to be hundreds or thousands of light years apart rather than the 5-10 (where we are in the Milky Way) or, say, in light weeks or less in the galactic center. It's known (and he talks about) stars being ejected fro…
The idea of having thousands's of light years of empty space with the same approximate black hole density as the galactic disk, but without the dust, gas, or stars to see their effects is rather a horrifying barrier to exploring the halo stars.
[1] This is a possibly theory. It is counter to axion theory (massive weakly interactive particles) as Axions require CPT violations we can't create experimentally, and LIGO is seeing collisions of black holes in the correct mass range, and which can't be created via stellar collapse (as they're just too big). Which lends some credibility to this mass range (also it wouldn't impact the CMB so the theory holds a fair amount of water).
I wonder how we'd feel as a species if our star was one of these instead of being the Sun. We'd see this amazing group of stars and planets, going away from us knowing the more we wait for space travel to less likely our species would to reach any other star system.
How would it impact a solar system if one of these relativistic stars got too close? Any chance it could pick up a few planets, or would they mostly be flung into space? Along that point, what does the heliosphere of such a star look like - a giant comet? Lastly, were a life-bearing planet sent into space this way have any chance of maintaining that life without a parent star to heat and magnetically shield it?
The heliosphere would look normal because there would be no drag on it. A comet has a tail because the sun is both melting and pushing material away from it.
Lastly, we could probably heat our homes with the core of the planet for a little while, but everything would be dead within a few years. I think the Twilight Zone covered this scenario in an episode! In it the Earth started moving away from the sun for no good reason.
I wonder how we'd feel as a species if our star was one of these instead of being the Sun. We'd see this amazing group of stars and planets, going away from us knowing the more we wait for space travel to less likely our species would to reach any other star system.
I wish that Banks had expanded on the idea with further novels as I really enjoyed reading about the cyclical rise and fall of societies while humanity explored different social/political structures, hoping to achieve some form of long-term stability.
Isaac Arhur touches on this subject in one of his videos, Intergalactic Colonization [1]. Basically, the void between galaxies isn't actually that much of a void. It's just in intergalactic space stars tend to be hundreds or thousands of light years apart rather than the 5-10 (where we are in the Milky Way) or, say, in light weeks or less in the galactic center. It's known (and he talks about) stars being ejected fro…
Dealing with dark matter halo's is likely non-trivial. While the science is still out, the most likely dark matter candidate is 15-50 solar mass black holes [1]. The idea of having thousands's of light years of empty space with the same approximate black hole density as the galactic disk, but without the dust, gas, or stars to see their effects is rather a horrifying barrier to exploring the halo stars. [1] This is a…
Isaac Arhur touches on this subject in one of his videos, Intergalactic Colonization [1]. Basically, the void between galaxies isn't actually that much of a void. It's just in intergalactic space stars tend to be hundreds or thousands of light years apart rather than the 5-10 (where we are in the Milky Way) or, say, in light weeks or less in the galactic center. It's known (and he talks about) stars being ejected fro…
https://medium.com/starts-with-a-bang/ask-ethan-can-stars-es...
Earlier quoted context omitted.
How would it impact a solar system if one of these relativistic stars got too close? Any chance it could pick up a few planets, or would they mostly be flung into space? Along that point, what does the heliosphere of such a star look like - a giant comet? Lastly, were a life-bearing planet sent into space this way have any chance of maintaining that life without a parent star to heat and magnetically shield it?
Chances are nothing would happen as space is vast, but if it did get too close, it would be going way faster than anything around it, as it would be on a different plane. It would just scanner whatever is nearby like a big boat in a small pond. The heliosphere would look normal because there would be no drag on it. A comet has a tail because the sun is both melting and pushing material away from it. Lastly, we could…