|  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
   
    | • | Remember – gravity is same as before, away from 
 |  | 
   
    |  | 
   
    |  | mass 
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    |  | 
   
    |  | – | Black holes do NOT necessarily pull all nearby material in 
 |  | 
   
    |  | 
   
    |  | – | A planet orbiting a new black hole would just keep on 
 |  | 
   
    |  | orbiting as before (assuming the ejected material or 
 |  | 
   
    |  | radiated energy didn’t have an effect) 
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    |  | 
   
    | • | Any mass can potentially be made into a black
    hole – 
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    |  | 
   
    |  | if you can compress it to a size smaller than RS
    = 
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    |  | 2GM/c2 
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    |  | 
   
    |  | – | 1 MSun: 3.0 km        106 MSun
    3106
    km         1 MEarth
    8.9 mm 
 | 
   
    |  |