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A black hole is a single point in space that has a lot of mass. One of the ways

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that we look for black holes is to develop new instruments

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and new technologies that can try to search for them.

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As we've observed black holes including the the supermassive black hole in the center of our galaxy,

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because it has such a strong gravity because it has lots of mass,

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stars will orbit black holes

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and as stars get closer and closer to the center of a black hole as it crosses over the Event Horizon,

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what will happen is that the material of these stars will get shredded apart,

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because the gravitational pull of a black hole is so strong that the material of the stars gets pulled apart.

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But there is an event horizon, which is the point at which the black hole's gravity

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starts to pull you so much that you can't escape.

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So as you approach the black hole, you'll feel its pull.

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But then as you get closer and closer and closer towards the event horizon, that's the point of no return so you couldn't

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escape past that.

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The easiest way to think of a black hole is just like anything that has mass so the Earth has mass

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And one of the reasons that the Moon orbits around the Earth

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is because the gravitational attraction of these two massive bodies. And so, Earth is distorting

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the space around the Moon and so that's what keeps the Moon in orbit. And so now take that to an extreme. So take

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something that's as massive as the Sun,

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or as massive as a million Suns and put it at a single point,

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and that distortion that you get is coming from that amount of mass in a single point.

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Black holes vary in size a lot. We know that black holes can be formed by massive stars exploding and then collapsing into

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the singular point.

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And those give us black holes that are about the mass of the Sun. So, those are solar mass black holes.

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However, we also know at the center of galaxies, like the Milky Way,

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there are supermassive black holes and these are millions or even billions of times the mass of the Sun.

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And how these form is actually a mystery. Studying black holes really gives us a fundamental insight

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into how gravity works because

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it's such a small physical scale, but it's a super massive object.

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And so understanding how black holes work and the

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interactions of black holes in other parts of the universe really give us a fundamental insight that we could then use to

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think about how our own solar system works.

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And so if we can understand how black holes work, they'll give us a key to really understanding our universe.