# Would a supermassive black hole accretion disk really vaporize solid objects?

Both the movie Interstellar and Greg Egan's Incandescence involve worlds deep inside accretion disks of large holes, kept at a comfortable temperature. Is this (remotely) realistic?

Although powerful and hot, the gas density in disks is very low and the size is large, so the radiant power in $\text{w/m}^2$ may not be that high.

The answer may depend on the "experimental setup": Test cases:

1. A small object (like a 1m sized stone) is inside the disk orbiting with it. It orbits close to the hole, perhaps 4 radii away (as in the stories).
2. The stone ploughs through the disk on an eccentric orbit at a relativistic speed, getting additional heating from the impact with the disk gas.

Conditions:

1. The Milky Way central black hole disk under normal conditions.
2. The Milky Way black hole during a "flare up" event.
3. A powerful quasar.

Which, if any of these, are survivable?

• Note that Kip Thorne said in The Science of Interstellar that he imagined that the accretion disk around the movie's black hole was at a much lower temperature than the one at the center of the galaxy--he says lower-temperature accretion disks "might be common around black holes that have not torn a star apart in the past million years or more--that have not been 'fed' in a long time. The magnetic field, originally confined by the disk's plasma, may have largely leaked away. And the jet, previously powered by the magnetic field, may have died." – Hypnosifl Jan 13 '15 at 2:49