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A comment on What If Planet 9 Is a Primordial Black Hole?. Parent comment

Re:What If Planet 9 Is a Primordial Black Hole? by 0-_-0 on Thursday September 26, 2019 @04:34AM (#21079235)
Wouldn't momentum transfer from the consumed mass slow it down?
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Re:What If Planet 9 Is a Primordial Black Hole? by sliken on Thursday September 26, 2019 @06:12AM (#21079636)
Some, but the sun isn't very dense. So sure if you were ever so slightly above escape velocity the consumed matter could slow you down.

A black hole the mass of the earth is 9mm. The weight of a cubic cm of sun is around 1.41 grams. The black hole isn't really going to notice.

The pass through the sun is around 1.39102e+11 cm * 1.41 grams per cm^3 = 139 million KG. So the earth weighs around 4.2* 10^16 more than what a black hole sized hole in the sun weighs.

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Re:What If Planet 9 Is a Primordial Black Hole? by 0-_-0 on Thursday September 26, 2019 @08:26AM (#21080261)
I thought its gravitational pull and the pressure around the black hole should cause it to absorb much more mass that that estimate.
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