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The cosmos can be a dangerous place.
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Take black holes for example.
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They're some of the most violent objects in our universe,
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powerful enough to rip entire stars to pieces.
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Their secret weapon is gravity.
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You see, the more mass you can shrink into a small space,
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the stronger your gravitational force will become.
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To make Earth into a black hole, for instance,
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you'd have to shrink it to less than an inch across.
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But real black holes are much larger than that
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and pack way more mass than Earth.
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Here's just how big black holes can really get.
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There are three common types of black holes.
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The smallest are stellar black holes,
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which form after a giant star explodes
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and collapses in on itself, like this one,
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which measures about 40 miles across,
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roughly three times the length of Manhattan.
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But in that small space
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is enough mass to equal 11 of our suns.
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In another galaxy called M33,
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there's a black hole that is 58 miles across
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and packs as much mass as 15.7 suns inside.
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Up next are the intermediate-mass black holes,
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like this one.
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At 1,460 miles across,
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it's nearly large enough to stretch from Florida to Maine,
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and according to some calculations,
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contains the mass of 400 suns.
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At this point,
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black holes start to get pretty big compared to Earth,
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but it's still nothing
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when you consider the sheer mass they carry.
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Take this black hole for example.
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It's nearly twice the size of Jupiter,
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spanning a region about 172,000 miles wide,
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but inside is as much mass as 47,000 suns.
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But these black holes are nothing
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compared to supermassive black holes,
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like Sagittarius A*,
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which lives at the center of our Milky Way galaxy.
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It covers a region about 14.6 million miles in diameter.
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That's roughly 168 Jupiters across,
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and inside is the same amount of mass
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as 4 million suns combined.
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Now, that may sound big,
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but Sagittarius A* is small
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compared to other supermassive black holes.
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Take the one at the center of our neighbor,
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the Andromeda galaxy,
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which has a diameter of 516 million miles,
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larger than Jupiter's orbit,
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and contains enough mass
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to equal that of 140 million suns.
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We're finally getting
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to some of the largest black holes in the universe,
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and yet, we haven't reached one
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that surpasses the size of our solar system.
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So let's look at the supermassive black hole
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at the center of the Sombrero galaxy.
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It measures 2 billion miles across,
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so it would stretch further than Uranus' orbit,
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and it has about the same mass as 660 million suns.
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And the supermassive black hole at the center of Messier 87
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is so huge that astronomers could see it
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from 55 million light-years away.
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It's 24 billion miles across
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and contains the same mass as
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6 1/2 billion suns.
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But this supermassive black hole, as large as it is,
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could still fit within our solar system
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with plenty of room to spare.
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So we have to look at one of the most massive
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of all supermassive black holes.
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It has a diameter of about 78 billion miles.
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For perspective, that's about 40% the size
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of our solar system, according to some estimates.
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And it's estimated to be
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about 21 billion times the mass of our sun.
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So there you have it,
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black holes can be millions of times larger
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than suns and planets or as small as a city.
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It all depends on how much mass is inside.
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Turns out, when it comes to the cosmos,
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size isn't the only thing that matters.