supernova_4

supernova_4 - mass but otherwise loses its density The...

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Black hole binaries Why can’t we see inside Recall escape velocity ---the velocity needed for something to “escape” the gravitational pull of an object For earth, Vescape ~ 11.2 km/s For moom, Vescape ~2-4 km/s For sun, Vsecape ~ 618 km/s For a black hole, Vescape > speed of light Light could not escape the Earth’s surface if you could shrink it to < 6 “Surface” of a black hole The “surface of a black hole is the radius at which the escape velocity equals the speed of light This spherical surface is known as the Schwarzschild radius No escape Means there is no more contact with something that falls in. it increases the black hole
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Unformatted text preview: mass but otherwise loses its density The event horizon of a 3 Msun black hole is also about as big as a small city. It increases with black hole masses If the sun shrunk into a black hole, its gravity increases with black hole masses Black holes The event horizon is where the escape velocity equals the speed of light. Once across, nothing can come back out Anything would become a black hole if compresses enough There are only holes in the observable universe...
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