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Two galaxies aligned in a way where their gravity acts as a compound lens

(phys.org)
268 points wglb | 2 comments | 16 Nov 24 16:48 UTC | HN request time: 0s | source
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waltbosz ◴[16 Nov 24 19:38 UTC] No.42158640[source]▶
One fun thing think about is that these two galaxies are only aligned from our perspective in the universe. Viewed from a different location, and they're just two normal galaxies.

Also, imagine having the technology to send signals through the lens and get the attention of intelligent life on the other side.

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snakeyjake ◴[16 Nov 24 20:57 UTC] No.42159262[source]▶
In order to use them as a signaling platform (how?) the signal would have needed to have been sent several billion years ago.

At 10 billion light years away from the most distant lens it is 100% certain that they are no longer in a gravitational lensing configuration.

For a frame of reference, the Milky Way will be in the middle of its epic merger with Andromeda in about 5 billion years.

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1. rjurney ◴[16 Nov 24 22:43 UTC] No.42160073[source]▶
It's kind of interesting in terms of analytics... can we predict when lenses will appear and disappear, from our perspective? What might we do with that information once we are more advanced?
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2. WJW ◴[17 Nov 24 00:01 UTC] No.42160711[source]▶
1. Yes it would be somewhat predictable to find these lenses for a civilization more advanced than ours.

2. Unless we find faster than light communication (which, with our current understanding of physics is about as likely as humans jumping to the moon) there is nothing we could use it for other than definite proof that other life has evolved in the universe. Interesting data, but they're most likely extinct for billions of years already and even if they're not, the compound gravity lens will have moved out of alignment by then so we have no means to send a message back.