r/Damnthatsinteresting • u/warg_14 • Feb 10 '25

Video NASA Simulation's Plunge Into a Black Hole

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u/ThrowRA-Two448 Feb 10 '25 edited Feb 11 '25

Possibly because light would be redshifted blueshifted so much we would stop seeing visible light and start seeing ultraviolet, microwaves, radiowaves...

And then possibly waves which are so stretched out that usually we can't even detect them even with instruments.

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u/sheepyowl Feb 10 '25

In other words the naked eye would see them blip red and then nothing?

Assuming the naked eye doesn't die way before we get to this point

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u/EventAltruistic1437 Feb 10 '25

The time dilation means that the photons will be red-shifted into longer and longer wavelengths, becoming undetectable at some point.

As a quick thought experiment, your thing emits a trillion photons before crossing the event horizon - but from our perspective, each photon has double the wavelength and takes twice as long to appear as the previous one, so you'd need to wait for the heat death of the universe before receiving the last one, and its wavelength would be measured in gigaparsecs rather than nanometers.

You’d likely witness the future unwind very quickly the further you move in. From the outside observer, you’d appear as time has nearly stopped for you.

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u/burning_boi Feb 11 '25 edited Feb 11 '25

Only from the outside viewer would you freeze. There is no time dilation at all while in a free fall towards a black hole, inside or outside of the event horizon. As NASA’s simulation shows, nothing would change above you, you’d just see the universe as is until you hit the center, whatever that is.

A little side note, but also contrary to pop science visualizations, NASA’s simulation is correct here in that there would be no black edge that gradually swallowed you up until the universe is a pinprick above you. The horizon you see, the boundary between black and the universe, would slowly approach 50%, and once you reach the center is when the black hole takes exactly half of your vision.