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mmazing

Imagine being a civilization on the edge of a galaxy on the edge of the void.

One direction, nothing whatsoever.

The other direction, billions upon billions of galaxies.

Would be neat!

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That's actually us - the Local Group (the Milky Way, Andromeda and other smaller galaxies, about 3 Mpc diameter) is part of the Local Sheet (about 5 Mpc × 0.5 Mpc) which is on the boundary of the Local Void (about 60 Mpc diameter).

https://en.wikipedia.org/wiki/Local_Void

* 1 megaparsec = 3.26 million light years

Imagine being a civilization alone in the void, and not even a generation ship could make contact with anyone else, even if they knew which direction to send it.

This article was written in 2007 about the Giant Void. [0] In 2013, the KBC Void [1] was discovered, named after its discoverers, Keenan, Barger, and Cowie. The KBC void is 2 billion light years across, twice the diameter and 8 times the volume of the Giant Void. Both the Giant Void and the KBC Void contain galaxies, the Giant Void containing 17 galaxy clusters, and the KBC Void containing the Laniakea Supercluster. [2] The Laniakea Supercluster contains the Milky Way. Something to imagine, indeed.

[0] https://en.wikipedia.org/wiki/Giant_Void

[1] https://en.wikipedia.org/wiki/KBC_Void

[2] https://en.wikipedia.org/wiki/Laniakea_Supercluster

Star Trek Voyager had an episode where the crew got lost in a void 2,500 light years across . . . pretty interesting.

https://memory-alpha.fandom.com/wiki/The_Void_(region)

The KBC Void our entire super-cluster is within is about 2 billion light years across...

https://en.wikipedia.org/wiki/KBC_Void

The Local Void that we are on one edge of is about 150 Mpc across (~490 million light years) and contains several "void galaxies" such as NGC 6503, about 4 Mpc (17 Mly) from us:

https://www.zmescience.com/space/the-local-void-mapped-04322...

https://en.wikipedia.org/wiki/NGC_6503

Two tiny dwarf galaxies are in the process of leaving the Local Void due to the attraction of the galaxies surrounding it:

https://www.space.com/33748-dwarf-galaxies-escape-cosmic-voi...

Sounds like you have a sci-fi novel to write!

https://en.wikipedia.org/wiki/Against_a_Dark_Background

Paints a bleak picture of a civilization in this situation. Great book though.

This is why I Love and lurk around in HN.

Thanks !

Came here to look for this comment :)

To a lesser degree: https://en.wikipedia.org/wiki/Life,_the_Universe_and_Everyth...

Well, even one galaxy is too big for anyone. As one astronomer said, even one local arm of Milky Way is enough to fit all and every science fiction ever imagined. There's just too much stuff, that you don't need to think about other galaxies.

Unfortunately that's actually what the future holds for the universe (as far as we can tell from current observations).

The universe will expand so much that civilizations into the VERY distant future will not be able to see other stars and galaxies, and will have no way to know that there's more out there.

It's quite sad actually.

I would be curious to hear if the odds of life existing on the edges of the universe were lower.

It should be the other way around. When everything is packed closer together you are far more likely to fall victim to supernovas, more asteroids and so on that can end life on your planet.

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