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I often think about how stars come within 1 light year of our Sun every 300,000 years. It's pretty wild. And then I have to worry about rogue planets, meteorite
by collaborative 3y ago
I often think about how stars come within 1 light year of our Sun every 300,000 years. It's pretty wild. And then I have to worry about rogue planets, meteorites, and obfuscated stars going supernova. What are the odds we're here?
- mongol 3y ago> Right now the star is about 250 light-years away, but 2.8 million years ago it passed within 30,000 AU or half a light-year of the Sun. It may have passed as close as 4,000 AU from the Sun. This blew my mind. I never considered that stars are moving relatively each other in this way. Or more precisely, what it meant for our solar system.
- silverquiet 3y agoSometimes people talk about hypothetical generation ships and the ethics of bringing children into such a situation where they will be expected to continue the mission throughout their lives. What’s funny is that in some sense we’re already on quite a large starship wondering near aimlessly through the galaxy. Obviously we could be treating it with much greater care than we currently are.
- aa1234556 3y ago[dead]
- hinkley 3y agoIf we never figure out FTL, if relativistic travel is hamstrung by blue shifting of particles and radiation in front of the craft, then the only other way we wander the galaxy is to hop over to a passing star. The question is, can you make a ship fast enough to catch a star going past, or do you have to launch ahead of time. And do you have enough time in either case to decide if this one way trip is suicide or not. Practically the window of opportunity for a favorable launch may not might not be that different than launching for Proxima Centauri. But at least you can soak up solar power and mine resources while you wait, instead of sitting in the dark the entire time.
- pfdietz 3y agoThis also means very long lived extraterrestrial civilizations can colonize the galaxy with slow very short range starships. Just wait for stars to come within a fraction of a light year and send over ships at 1% of the speed of light (or even slower). The star will move away, and it also becomes a target for close approaches of stars. The number of colonized stars grows exponentially (if gradually) until most stars have been colonized.
- alserio 3y agoSorry, I'm not getting this. The star will move away from what? Wouldn't the spaceship move with the star? I apologize if I'm misinterpreting what you said
- mtlmtlmtlmtl 3y agoOnce you've colonised the star system during its close passage to your own, it will continue its journey and eventually pass nearby other star systems, which can then be colonised as well. So every colony will spawn more colonies, leading to exponential growth. At least I think that's what they meant. It's an interesting idea for sure.
- pfdietz 3y agoYes, that's exactly what I meant.
- 0cf8612b2e1e 3y agoI think they mean that if you start in solar system A, when solar system B flies by, you enter its gravity and colonize the system. Eventually solar system B will fly by solar system C, where you can repeat the process.
- dboreham 3y agoB-Arc
- 3y ago
- zbaxrl 3y agoGliese 710 will be at a 0.16ly distance in 1.3 million years. Well within the Oort Cloud. https://en.wikipedia.org/wiki/Gliese_710 https://en.wikipedia.org/wiki/Gliese_710
- GMoromisato 3y agoQuick! Someone write a sci-fi screenplay set in that time period! A star inside the Oort Cloud might start another inner system bombardment.
- andsoitis 3y ago> how stars come within 1 light year of our Sun every 300,000 years. A few years ago, research using Gaia data indicated that the last such close encounter was about 70,000 years ago, when the star WISE J072003.20-084651.2 — also called Scholz’s Star, after the discoverer — passed just 0.8 light-years from the Sun. - https://www.syfy.com/syfy-wire/bad-astronomy-several-stars-have-come-within-a-light-year-of-the-sun https://www.syfy.com/syfy-wire/bad-astronomy-several-stars-h...