Expert: Jayendra Upadhye - 7/21/2008

Question
If the Sun were to suddenly become a black hole (I understand it can't) what would happen to the Earth's orbit?

Answer
Hi Cindy,
If the an advanced civilisation were to suddenly work its magic and cause the sun to implde into a black hole, the following would happen.
1 - The earth's orbit which is a function of the mass of the sun and that of the earth would be unaffected.
   (As both these masses would be still the same).
2 - We would all die as the earth cooled off.
   Even before the food stocks ran out, we would frezze to death.
   Eventually.
3 - The cooling atmosphere would start precipitating rain and snow in a global ice age.
4 - The niagara would freeze with all other rivers over the world.
4 - The gases in the atmosphere, depending on their dew points, start to "rain down" one by one, as their triple points were reached.
5 - With each such precipitation, that much partial pressure of that gas would be subtracted from the atmosphere.
6 - In the end we would be directly staring at space, but swimming in an ocean of liquid gases fractionated neately by their atomic weights, with hydrogen forming a very thin viel over evrything.
7 - After a time, earth would reach the "temperature" of interstellar space, (that of the cosmic background radiation, which is about 3 degrees kelvin).

Hope that suffices.

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regards
Jayen