alt Hacker NewsNot an astrophysicist, but I'm thinking 5 AU could quickly fry the Earth - because it takes very little in the way of solar comets, asteroids, and dust to build a temporary accretion disk around such a black hole. That disk might have a temperature of >1M degrees. Plus the dynamo effects of the disk's interactions with the solar magnetic field? Yeah. 5 ly sounds much safer.
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ben_w • yesterday at 4:14 PM
> Yeah. 5 ly sounds much safer.
Well yeah.
I clearly could've phrased this better though: I was aiming for "here is an example distance which *is* bad", not as it appears to have been understood "here is the distance where it is *not* bad".
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Yeah, I'm sure you're right. I was looking purely at orbital mechanics and gravity, but I think a four-stellar-mass black hole would certainly have other harmful environmental effects that would be felt at that range.