- #1
Daharen
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So I'm trying to help someone get an idea of the 'scale' of some of the most massive black holes, but, I'm at best a laymen when it comes to this stuff. Because ISCO for a non-rotating black hole is just 3 times it's radius, and I can calculate apparent arc radius from ISCO, I could tell them how large it would appear if our solar system orbited the black hole at the ISCO, but then I was asked how long it would take to 'fall' into the black hole if we suddenly stopped orbiting (A very similar question to the classic how long it would take to fall into the sun if the Earth stopped orbiting, but on a very different scale).
Now... I imagine this gets quite complicated quite fast since at this point we're not just dealing with simple Newtonian Mechanics, but probably a lot of relativistic stuff too.. However, if we can disregard relativity for the sake of this conversation, how long would it take for a planet that was orbiting TON 618 at about 3900 AU from it's Event Horizon, and suddenly stopped orbiting and went into free fall, to reach the event horizon, which is about 1300 AU from the singularity, given a mass of 66 Billion Solar Masses?
If this is beyond the reasonable scope of this forum I understand, I tried really hard to work with calculators to find the answers, but couldn't account for the change in acceleration over time (Integral Calculus is definitely not my strong point).
Now... I imagine this gets quite complicated quite fast since at this point we're not just dealing with simple Newtonian Mechanics, but probably a lot of relativistic stuff too.. However, if we can disregard relativity for the sake of this conversation, how long would it take for a planet that was orbiting TON 618 at about 3900 AU from it's Event Horizon, and suddenly stopped orbiting and went into free fall, to reach the event horizon, which is about 1300 AU from the singularity, given a mass of 66 Billion Solar Masses?
If this is beyond the reasonable scope of this forum I understand, I tried really hard to work with calculators to find the answers, but couldn't account for the change in acceleration over time (Integral Calculus is definitely not my strong point).