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Black holes keep 'burping up' stars they destroyed years earlier, and astronomers don't know why (www.livescience.com)

submitted 1 year ago by [email protected] to c/[email protected]

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[–] [email protected] 23 points 1 year ago (2 children)

I remember when I used to believe that nothing escaped a black hole past the event horizon. I remember when I used to think a black hole was an actual hole. I sure hope Santa isn't late this year. There are some things still with believing in.

[–] [email protected] 23 points 1 year ago* (last edited 1 year ago) (1 children)

You're still right about that first part. It's a poorly written headline, all of the matter being ejected hasn't passed the event horizon

[–] [email protected] 10 points 1 year ago

There's the hard event horizon and then there's multiple radii past it with different effects on orbits (such as the photon orbit radius, stable circular orbit radius, etc) and if you're very close you're also dealing with "weaker" horizons like a radius where most light gets redshifted past visibility even if mass can still escape if it's fast enough.

https://profoundphysics.com/black-hole-orbits/

[–] [email protected] 4 points 1 year ago (1 children)

I remember when I used to believe that nothing escaped a black hole past the event horizon.

I mean, nothing does, so why did you change your beliefs?

[–] [email protected] 1 points 1 year ago (1 children)

Hawking radiation.

[–] [email protected] 2 points 1 year ago

Hawking radiation isn't something leaving the event horizon, it's created outside. Nothing that is inside can leave.