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Gaia spots stars flying between galaxies

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Re: Gaia spots stars flying between galaxies

#41

Post by njarboe »

TeMPOraL wrote: post #8
wlesieutre wrote: post #6

Earlier quoted context omitted.

We had a "close" flyby (0.82 lightyears) about 70,000 years ago! https://en.wikipedia.org/wiki/Scholz%27s_Star

> A star is expected to pass through the Oort Cloud every 100,000 years or so.[4] An approach as close or closer than 52,000 AU is expected to occur about every 9 million years.[2] In about 1.4 million years, Gliese 710 will pass somewhere between 8,800 and 13,700 AU from the Sun. Just wow.

Maybe interstellar travel is basically impossible but there might be very long lived civilizations that propagate to others stars when one comes near by. Imagine what happens when both stars are populated by different long lived civilizations and they start to get near each other. I would love to read a good book speculating about such an event.

Re: Gaia spots stars flying between galaxies

#42

Post by TeMPOraL »

ryandrake wrote: post #40
behringer wrote: post #36

Earlier quoted context omitted.

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…

See “A Pail of Air" by Fritz Leiber: https://en.m.wikipedia.org/wiki/A_Pail_of_Air

A great story. Also, for some reason, it shook me deeply. I still feel dread when I think of it. Such hopeless scenario for humanity.

Re: Gaia spots stars flying between galaxies

#44

Post by thaumasiotes »

kbenson wrote: post #15
TeMPOraL wrote: post #5

Earlier quoted context omitted.

I have this science fiction writing/game backstory idea I recently came up with. Feel free to use it, as I guess I won't get around to do anything with it any time soon. Copying straight from my "ideas" file: At some point in time (past or future, or magically also present), a star passed in very close vicinity to our sun. It had a habitable planet in its system, full of alien plant and animal life. For the brief mom…

Wow. Just the changed mindset (compared to the present, at least) would be amazing. "Are there others out there? Yes. And they're like us. We should try to meet again some day." It's almost like a modern day Atlantis myth, but true. If you want a really interesting setting for a game/book, imagine a major regression on Earth (standard post-apocalypse trope), and the colonists finally find a way to visit again...

> Are there others out there? Yes. And they're like us.

By the time we managed to meet them again, there would be no reason to expect them to be like us.

> If you want a really interesting setting for a game/book, imagine a major regression on Earth (standard post-apocalypse trope), and the colonists finally find a way to visit again...

This is a regular feature of Motie civilization in the series beginning with The Mote in God's Eye.

Re: Gaia spots stars flying between galaxies

#45

Post by hyperpallium »

TeMPOraL wrote: post #5
alex_duf wrote: post #2

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 have this science fiction writing/game backstory idea I recently came up with. Feel free to use it, as I guess I won't get around to do anything with it any time soon. Copying straight from my "ideas" file: At some point in time (past or future, or magically also present), a star passed in very close vicinity to our sun. It had a habitable planet in its system, full of alien plant and animal life. For the brief mom…

Pedantically, wouldn't Δv-accessible mean it would take a long time to get here, and we'd see it coming for a very long time?

Possibly easy to address... maybe, it was small and dim, and in line with a bright star, so we'd interpreted it wrongly.

Re: Gaia spots stars flying between galaxies

#46

Post by abecedarius »

pavel_lishin wrote: post #28
alex_duf wrote: post #2

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.

There's at least two stories I've read with a similar premise; one was an interesting tale of a planet that stifles its scientific development, and is almost-unaware that they're about to approach another star. Damned if I remember what it's called, or who wrote it, though...

Perhaps https://en.wikipedia.org/wiki/The_Collected_Stories_of_Verno...

Re: Gaia spots stars flying between galaxies

#47

Post by kbenson »

thaumasiotes wrote: post #44
kbenson wrote: post #15

Earlier quoted context omitted.

Wow. Just the changed mindset (compared to the present, at least) would be amazing. "Are there others out there? Yes. And they're like us. We should try to meet again some day." It's almost like a modern day Atlantis myth, but true. If you want a really interesting setting for a game/book, imagine a major regression on Earth (standard post-apocalypse trope), and the colonists finally find a way to visit again...

> Are there others out there? Yes. And they're like us. By the time we managed to meet them again, there would be no reason to expect them to be like us. > If you want a really interesting setting for a game/book, imagine a major regression on Earth (standard post-apocalypse trope), and the colonists finally find a way to visit again... This is a regular feature of Motie civilization in the series beginning with The…

> By the time we managed to meet them again, there would be no reason to expect them to be like us.

Depending on technological advancements and how "hard" you want to consider your sci-fi or future science (purely based on likely developments of current technology, etc), how close to Earth conditions you want to assume the other planet was, how much you believe humans are still evolving, whether you think humans are likely to evolve along similar paths if segregated, whether we are considering mental models only or physical likeness...

So yes, no reason necessarily to expect them to be, but some small chance depending on a lot of factors lining up.

> This is a regular feature of Motie civilization in the series beginning with The Mote in God's Eye.

Yes, it's not an original trope. The rogue star explanation is one of the more feasible I've heard though.

Re: Gaia spots stars flying between galaxies

#48

Post by Razengan »

Stars outside galaxies, planets without stars, asteroid clusters drifting through nebulas, worlds orbiting black holes..

We are tantalized with so many possibilities to be explored, without being able to go out and touch them.

I really wish humanity or at least some nations would focus on direct exploration of the cosmos. It would open up entire new industries, provide more jobs, and more beneficial side effects compared to how much we spend on war and preparing for war.

Most importantly perhaps, it could provide a collective sense of hope and purpose that seems to be increasingly missing from our species.

Re: Gaia spots stars flying between galaxies

#49

Post by sehugg »

graedus wrote: post #34
mitchty wrote: post #18

Earlier quoted context omitted.

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.

> An example, the collision of the Milky Way with Andromeda is likely to produce no collisions of solar systems. 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 ce…

There used to be a relevant X screensaver ... ah, here's a port of it to JS: https://rtoal.github.io/galaxies/galaxies.html

Re: Gaia spots stars flying between galaxies

#50

Post by japanuspus »

Ush2iaph wrote: post #7

What better intergalactic colony ship than a whole star system accelerated to a significant fraction of c.

If you are into big history science fiction, I highly recommend "The Wandering Earth"[1] by Liu Cixin, which explores this theme (sort of). Short enough to read in a night.

[1]: https://www.goodreads.com/book/show/13554058-the-wandering-e...

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