Tawny Zamudio Black Holes
Feb 24, 2016
Tawny ZamudioBlack Holes
What is a Black Hole?Black holes are the evolutionary endpoints of
stars at least 10 to 15 times as massive as the sun.
Cont.If a star that
massive undergoes a supernova
explosion, it may leave behind a fairly
large burned-out stellar remnant.
With no outward forces to oppose
gravitational forces, the remnant will
collapse in on itself. The star eventually
collapses to the point of zero volume and
infinite density, creating singularity.
Around the singularity is a region where the force of
gravity is so strong that not even light can escape it.
No information can reach us from this region. This is why it is called a black hole.It’s surface is called the Event Horizon.
History…The idea of a body so massive that even light
couldn’t escape was first put forward by geologist, John Michell.
If the semi-diameter of a sphere of the same density as the Sun were to exceed that of the Sun in the proportion of 500 to 1, a body falling from an infinite height towards it would have acquired at its surface greater velocity than that of light, and consequently supposing light to be attracted by the same force in proportion to its vis inertiae, with other bodies, all light emitted from such a body would be made to return towards it by its own proper gravity.
—John Michell
What types of black holes are there?
Often, black holes look very different from each other, but this is because of their surroundings.
Black holes themselves are identical, except for three characteristic properties:
The massIt’s spinIt’s electric charge
Astronomers can measure the mass of black holes by studying the materials that orbits around them.
So far, astronomers have found two types of black holes:
Stellar-massSupermassive
Stellar-mass black hole
Supermassive black hole
The nearest black hole is many lightyears away.
We never have to worry about Earth being sucked in.