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  • Imagine you're out for a walk on a lovely day,

  • with not a care in the world.

  • The birds are singing,

  • and the Sun is shining.

  • Actually, the Sun seems brighter than usual.

  • And come to think of it,

  • your skin feels kind offunny.”

  • It turns out that's not the Sun at all,

  • but the radiation and gamma-ray filled light

  • coming from a quasar!

  • In short,

  • you're in serious trouble.

  • I hope you didn't have any plans today,

  • because the brightest object in the sky

  • has set up shop in our Solar System.

  • A quasar is the result of

  • two black holes colliding

  • to form a supermassive black hole,

  • with a central mass that outweighs our Sun

  • by a billion times.

  • When black holes merge,

  • everything goes out of whack.

  • The two black holes begin to consume

  • all the gas and dust from each other,

  • along with anything else in the area.

  • Ok so, if they're eating each other,

  • why are we seeing that bright light?

  • Well, the material that's thrown off

  • begins to glow from pressure and friction,

  • resulting in the blinding light you're seeing.

  • If this were to happen in Earth's vicinity,

  • it would be a result of the black hole

  • in the middle of the Milky Way galaxy

  • smashing into the black hole

  • at the middle of the Andromeda galaxy,

  • which is 2.5 million light-years away.

  • If these two met,

  • we'd be looking at a massive amount

  • of infrared light being

  • expelled into the Universe.

  • Oh, and it's also a harbinger

  • of death and destruction, too.

  • Well, brace yourself,

  • because this is going to be a doozy.

  • Quasars throw off jets of particles

  • that are so bright they outshine

  • all the stars in their galaxies.

  • So our Sun would essentially

  • turn into a candle

  • in the middle of a very bright spotlight.

  • The illumination from a quasar,

  • along with all the radiation it throws off,

  • would mess with Earth's atmosphere.

  • The light is enough to energize particles

  • that make up the atmosphere and free them

  • from Earth's gravity.

  • Our atmosphere would be destroyed.

  • And we really need our atmosphere.

  • It's our protective layer

  • that keeps things in order,

  • and regulates the temperature.

  • Without it, the oceans would dry up,

  • Arctic ice would turn into water vapor,

  • and everything would get much, much hotter.

  • In addition to it being blindingly bright,

  • we would have no safe air to breathe,

  • no plants to eat or feed animals,

  • and there would be no water to drink.

  • Life on Earth would be a write-off.

  • This would all happen very quickly,

  • so you wouldn't have to live through

  • a long, drawn out apocalypse.

  • At least look forward to that.

  • But could this sort of doomsday scenario

  • actually occur?

  • Well, yes,

  • but not for another 3 or 4 billion years.

  • At that point, the Sun will be flickering out.

  • And by that time we're pretty sure

  • something else we've covered on WHAT IF

  • would have taken us out first,

  • so we won't even be around to see it.

  • But it makes us wonder

  • what other mysteries could be found

  • hiding in black holes.

  • Could we harness the energy of a black hole?

Imagine you're out for a walk on a lovely day,

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