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Gaia spots stars flying between galaxies

sciencedaily.com

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Re: Gaia spots stars flying between galaxies

#21

Post by Boulth »

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…

This reminds me of Clarke's Rama.

Re: Gaia spots stars flying between galaxies

#23

Post by TeMPOraL »

soraki_soladead wrote: post #19
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...

Wasn't this sort of the idea behind the Homeworld games? Ancient artifact discovered in Antartica, left by the original settlers of Earth, leads to a quest to travel "home".

Sort of. It wasn't Earth, and the artifact was found in a desert.

Re: Gaia spots stars flying between galaxies

#24

Post by stcredzero »

Flow wrote: post #22
Ush2iaph wrote: post #7

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?

Shkadov Thrusters

https://www.youtube.com/watch?v=_VetAm7fCS0

Re: Gaia spots stars flying between galaxies

#25

Post by cletus »

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 from galaxies. This is important because a lot of intergalactic stars have high metallicity and are likely to at least some of the time still have their planetary systems.

It is interesting to consider where these stars came from. A nearby galaxy being the obvious candidate. I wonder if the 3D velocity measurements can be precise enough to ever determine this to a high degree of likelihood. It would be cool to find some intergalactic visitors in our own galaxy.

[1]: https://www.youtube.com/watch?v=xRB7a89Jh7w

Re: Gaia spots stars flying between galaxies

#26

Post by soraki_soladead »

TeMPOraL wrote: post #23
soraki_soladead wrote: post #19

Earlier quoted context omitted.

Wasn't this sort of the idea behind the Homeworld games? Ancient artifact discovered in Antartica, left by the original settlers of Earth, leads to a quest to travel "home".

Sort of. It wasn't Earth, and the artifact was found in a desert.

Yep, you're right[0]. It's been a while.

[0] https://en.wikipedia.org/wiki/Homeworld#Plot

Re: Gaia spots stars flying between galaxies

#27

Post by jacquesm »

aaroninsf wrote: post #12
Ush2iaph wrote: post #7

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

Had the same thought... it's the Westfalia camper of a Class 2.5 civilization.

Hope they have invented a better zipper then!

Re: Gaia spots stars flying between galaxies

#28

Post by pavel_lishin »

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...

Re: Gaia spots stars flying between galaxies

#29

Post by def_ConGame »

stcredzero wrote: post #24
Flow wrote: post #22

Earlier quoted context omitted.

But how can a civilization even start to move a star to a degree it fills a purpose?

Shkadov Thrusters https://www.youtube.com/watch?v=_VetAm7fCS0

That guy's channel is awesome, but his Rhotacism drives me up the wall.

https://en.wikipedia.org/wiki/Rhotacism_(speech_impediment)

Re: Gaia spots stars flying between galaxies

#30

Post by jetrink »

The abstract of the paper says that the two fastest stars are traveling at 700 km/s. For scale, at that speed, a star would take 20 million years to travel from the outer edges of the galaxy to the center. (That ignores any acceleration as the star falls inward, of course.)
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