If you want a good source on stars

and the black holes they can become,

get the March 2014 issue of

National Geographic

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One item:  If the Earth collapsed into

a black hole, it would become the

size of a marble…and still 

“weigh” the same…

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For more use the DOOR.

 

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[MORE]

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Our basic picture of atoms is a nucleus made of protons and neutrons stuck together in a ball with electrons speeding around it “far” away, or with a lot of space between them.

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But these atoms aren’t sitting still. Some forces like gravity tend to smush them together. Other forces tend to blow them apart and/or make them whirl.

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Now let’s jump from atoms to stars.

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That said, let’s let NG explain Black Holes, a concept, an understanding, a reality that’s only been with us since the middle 20th century. Some direct quotes from pp. 92-99. (We’ll color NG’s comments blue. Our comments will be colorless.)

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The Power of Gravity

“Einstein showed a century ago that the mass of stars, planets, and all other matter exerts a gravitational force, bending space like a rubber sheet. The greater the mass of an object, the more powerful the effect. The immense mass of a black hole generates a gravitational ‘sink’ from which not even light can escape.”

[Consequently, this heavy, heavy thing can't even be seen because even the light that would show us its location is imprisoned by its "power." That means it's invisible.]

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A Star’s Birth–and Death

“Each star is a balancing act, with crushing gravity pulling inward against and interior nuclear blast furnace pushing out. When the star’s fuel is exhausted, gravity wins and the star implodes. But its fate and the elements it forges before its collapse are foretold by the original size. The more massive the star, the more violent its ending.”

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[Now we will overgeneralize:

(1)  Smaller used-up stars collapse and become white dwarf stars.

(2)  Larger used-up stars collapse and become neutron stars.

(3)  The heaviest used-up stars collapse "infinitely deep" to become black holes, invisible, but exerting tremendous power.]

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If you want to understand more about all this–and many of you can learn new things from just these words–get the March 2014 National Geographic for the bookshelf you have left that really holds books. [Excellent charts, pictures and explanations.]