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

(phys.org)
268 points wglb | 1 comments | 16 Nov 24 16:48 UTC | HN request time: 0.213s | 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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OlleTO ◴[17 Nov 24 11:03 UTC] No.42163428[source]▶
So conceiably someone could have sent a signal from the other part of the lense some billion years ago and we "just" need to figure out what to listen for.
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1. reubenmorais ◴[17 Nov 24 11:31 UTC] No.42163549[source]▶
I don't think so, that would mean these "someones" would have to be developed enough to send interstellar messages through gravitational lenses when the very first solar systems and rocky planets were being formed, around 10 billion years ago. It seems too early for technology at that level.