Greg Egan on Nostr: One thing that really surprised me when I did these calculations was how far away the ...
One thing that really surprised me when I did these calculations was how far away the falling astronauts “looks” from the spacecraft. The black hole itself is at a distance of 12 M (where M is the mass of the hole, and we are using geometrical units where masses and distances are measured in the same units) ... but the curvature of the light rays is enough to make the falling astronaut appear to be at a distance of almost 70 M!
[In reality, the redshift would render the falling astronaut completely invisible, but as a theoretical measurement you could make at long wavelengths, maybe for a star falling into a supermassive black hole, this is still quite striking.]
Published at
2024-12-02 10:38:57Event JSON
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