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  • Hey there and welcome to Life Noggin.

  • Black holes are some of the strangest places in the universe.

  • They are points in space where the gravity is so strong, nothing can escape their pull.

  • Most black holes are created when a dying star runs out of fuel.

  • If the star is large enough, it starts to collapse in on itself.

  • As its matter is compressed, it becomes so tightly packed into such a small space that

  • its gravitational force becomes huge -- and I mean really huge.

  • Black holes can pull in planets, stars... even light can't escape their grasp.

  • The Milky Way alone contains up to a billion of these so-called stellar black holes -- stellar,

  • because they are formed by collapsing stars, and also, I assume, because they're awesome.

  • They range in mass but are formed from a star that are at least 3 times as massive as our sun.

  • And it's the mass that counts, not the size.

  • If a star the mass of Earth became a black hole, it would end up being only the size of a marble!

  • Imagine holding the entire mass of the earth in the palm of your hand.

  • Of course, you couldn't really do that because the extreme gravitational pull would destroy

  • you...along with your house, your neighborhood, and the entire planet.

  • Let's move on.

  • But there is something even larger than a stellar black hole.

  • Supermassive black holes can be millions or even billions of times as massive as our sun.

  • They can result from stars crashing into each other or smaller black holes merging together.

  • Astronomers think it's likely that every galaxy has a supermassive black hole at its center -- even the Milky Way.

  • So, should we be worried that we'll suddenly be sucked into a black hole and torn apart?

  • Well, we're ok for now.

  • The closest supermassive black hole to us, Sagittarius A, is 26,000 light years away.

  • And you can't be pulled in unless you get really close to one.

  • For example, if our sun were to somehow become a black hole, it would still have the same mass,

  • just condensed, and Earth would continue orbiting it like normal.

  • Of course, we'd probably miss the solar radiation.

  • But what if we did encounter a black hole?

  • What happens inside of one?

  • Every black hole contains an event horizon, the point of no return, after which nothing can escape.

  • Inside of this is the singularity -- the place where the star has collapsed down until it has zero volume and infinite density.

  • Since everything past the event horizon disappears, it's really hard for us to know what's going on in the singularity.

  • Maybe it's a huge party being thrown, and I wasn't invited.

  • In fact, because black holes don't emit anything on their own, we've never actually seen one.

  • We only know about them because of how they affect the matter around them.

  • When the gases and dust of nearby galaxies get pulled into the event horizon, the atoms gain energy and heat up.

  • This causes them to emit radiation that we can read here on Earth.

  • Using this radiation, astronomers have a plan to create the first-ever image of a black hole!

  • This isn't the kind of picture you'd snap on your phone and share on Instagram.

  • Instead, 12 teams around the world will set up radio telescopes calibrated to the same

  • frequency -- 230 gigahertz -- all pointed at our supermassive black hole neighbor, Sagittarius A*

  • Their data will be pieced together as if it came from one giant, earth-sized radio telescope.

  • If it works correctly, researchers think that we'll be able to see the ring of radiation around Sagittarius A*.

  • So, although we won't technicallyseethe black hole itself, we'll essentially

  • be able to see its outline and the dark shadow that the black hole casts on the radiation.

  • This experiment could help us finally confirm that black holes do exist.

  • It could also be used to study how black holes change over time, how their magnetic fields work, and even how they destroy materials.

  • It's going to take quite a few months to get the data processed, so look for results in 2018.

  • But when it's done, good old Sagittarius A* will be thestarof the show.

  • I hope it's ready for its close up.

  • Interesting question here, so, what would you most want to take a picture of in space?

  • A black hole?

  • A distant planet?

  • Let me know in the comments below!

Hey there and welcome to Life Noggin.

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地球はブラックホールに吸い込まれるのか? (Will Earth Ever Be Sucked Into A Black Hole?)

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    Jerry Liu に公開 2021 年 01 月 14 日
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