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00:00Black holes are the densest areas of spacetime known to humanity.
00:05Their gravitational pull is so extreme that not even light can escape them, making them
00:09appear invisible.
00:11No one knows what truly lies inside.
00:14They are one of the most mysterious astronomical objects of all.
00:17So what would happen if someone fell inside?
00:20Or even worse, what if our entire planet was consumed?
00:24This is Unveiled, and today we're answering the extraordinary question, what if Earth
00:28fell into a black hole?
00:30Do you need the big questions answered?
00:32Are you constantly curious?
00:34Then why not subscribe to Unveiled for more clips like this one?
00:37And ring the bell for more thought-provoking content!
00:41Einstein proposed his theory of general relativity in 1915, and shortly after, it was found to
00:47predict black holes.
00:49Forty years later, the first black hole, Cygnus X-1, was detected.
00:53It would still be another fifty years, however, until scientists directly imaged a black hole
00:58for the first time.
00:59This happened in 2019, more than a century after we first theorized them.
01:04So what do we know for sure?
01:05For one, black holes are the densest objects in the universe.
01:09They mostly form from the remains of dead stars.
01:12Most large galaxies rotate around a supermassive black hole at their centre, which are especially
01:18colossal objects.
01:19The Milky Way's supermassive anchor is named Sagittarius A-star, and it's currently measured
01:24to be 4.3 million times the sun's mass.
01:28Due to their invisible nature, it's far easier to observe black holes indirectly, through
01:33their orbiting bodies, rather than directly imaging them.
01:37We notice their presence by measuring their effect on everything around them, all of which
01:41means that as of today, we've managed to catalogue at least fifty black holes in the Milky Way.
01:46An impressive feat.
01:48However, experts believe there to be at least 100 million left to find.
01:52Gaia BH1 is the closest one we've found, being roughly 1,500 light-years away.
01:58But with so many predicted, much closer black holes are likely.
02:02So, with our title question, is it possible right now for us, for our planet, to fall
02:07into one?
02:08Unfortunately, yes, it's possible.
02:12Entire worlds can meet their fates to black holes.
02:14However, for Earth, it's extremely improbable.
02:18Estimates vary, but they're all huge.
02:20Perhaps there's a one in forty or fifty billion chance of it happening every year.
02:25With the cosmic scales being so wide, it's generally expected that we'd fall into the
02:30sun when it goes red giant in around five billion years' time, much sooner than we
02:34will ever fall into a black hole.
02:36Still, because black holes are so common, we can't rule it out entirely.
02:41And if it were to happen, then the gravitational effects in general would likely be so immense
02:46that we'd spot them long before the worst happens.
02:49Indeed, were Earth to be approaching a black hole, then we would find ourselves warped
02:54beyond survival long before we actually passed that infamous point of no return, the event
02:59horizon.
03:00But the truth is that researchers currently have no real idea what actually happens inside
03:05a black hole.
03:06It's also a mystery where the matter they consume goes.
03:10From the outside, we can't see past the event horizon.
03:13We can see the accretion disk, though, which is a black hole's most visible component.
03:18This is a swirling region of incredibly hot gas and dust particles, typically spinning
03:22beyond ninety percent of the speed of light, which creates a great deal of electromagnetic
03:27radiation.
03:29If Earth ever were heading in, then this would be our planet's final call.
03:33Ultimately, it would be the same for just a singular observer falling in as well.
03:37First the accretion disk would need to be traversed, getting hotter, brighter, and orbiting
03:42faster the further in you moved.
03:44But other than the high temperatures and quick orbit, everything would still behave fairly
03:48normally.
03:49The main peculiarities unfold at the horizon.
03:52Time warps as well as space at this point, leading to various mind-bending effects.
03:57For one, it's thought that were a person to fall in, then from the outside they would
04:02never appear to cross the event horizon at all.
04:05Their image would gradually get redder and redder, becoming more and more distant, before
04:10eventually fading away completely… but it would appear as though they'd never crossed
04:14over entirely.
04:16To some degree, it'd be more like they had simply frozen forever.
04:20Back to the inside, and from our individual's perspective, it may be that they never actually
04:25noticed they're crossing the event horizon, either.
04:28But that said, their body is now inescapably primed for one of the most primal and violent
04:33processes in the cosmos… spaghettification.
04:37This is pretty much what it sounds like.
04:39Due to changing tidal forces at and around the event horizon, our person will be continually
04:44stretched towards the very centre of the black hole.
04:47And eventually, they'll become so stretched that their body loses all recognisable integrity.
04:53Of course, by now they're dead… but if they were somehow able to witness themselves,
04:57then they'd perhaps see their own feet by looking straight upwards.
05:01Far along, though, even those feet would be no more.
05:04Their body would instead be stripped all the way back down to just the very most fundamental
05:09particles that make it.
05:11In the end, they're just one long line of tiny, tiny pieces.
05:15So, that's one answer as to what would happen if Earth fell into a black hole.
05:19Every living thing on it would get spaghettified… but surely the planet itself could never disintegrate
05:24so completely.
05:25Say a black hole moved as close to us as the moon… then yes, it may well disrupt life
05:30beyond saving… but could the whole world really be erased, too?
05:34Unfortunately, it can and would be.
05:37Among the earliest signs would be massive and unpredictable changes incurred by shifting
05:42tidal forces generated by the presence of the black hole.
05:45But, and while the gravitational forces are cause for concern, it's the radiation that
05:50would hit us first.
05:52Again, black hole accretion disks are extremely hot and radiated, which means that Earth would
05:57likely be scorched first of all… and we'd all be cooked.
06:01Our atmosphere would be completely ripped away as part of this, with its remnants being
06:06amongst the first bits of Earthly matter to be funnelled into the black hole, never to
06:10be seen again.
06:12The heat and violent winds that are then allowed to form would be so intense that they'd
06:17strip the rest of the surface.
06:18Soon, even our largest mountains would be reduced to nothing.
06:22Axial tilt and rotation speed would no longer be measurable or relevant, meaning that the
06:27same might not be happening everywhere all at once.
06:30But before long, the black hole would level the world as we know it.
06:34Next up, and the oceans would follow the atmosphere, siphoning off into space before disappearing
06:39forever.
06:40Then we'd have volcanic eruptions unlike anything ever known, exploding across all
06:46even slightly vulnerable regions.
06:48Now is when the black hole's power begins to break the inner Earth as well as the outer.
06:53The surface is awash with freshly released magma, all of which is also inescapably spiralling
06:59and dissolving in the direction of the black hole.
07:01Earth's tectonic plates, usually so vital to its most incontestable natural rhythms,
07:07start to break apart.
07:08This means huge earthquakes at first, before a total removal of the crust.
07:13The plates are no more, and the mantle is exposed, and promptly drained.
07:18All that's left is the core, before even that, the outer, then the inner, is broken
07:22down and bled dry.
07:24By this point, Earth is completely lost.
07:27All its parts are spread across the accretion disk, whittling still further down into smaller
07:32and smaller pieces.
07:34All the energy it once held is turned into accreting hot gas and radiation, and nothingness.
07:40The black hole would move on, digesting its latest meal without ceremony.
07:44Earth, humankind, and life in general would be no more.
07:48What happens to the very most basic parts once everything has been separated?
07:52As we don't know what's inside a black hole, beyond the total breakdown of physics,
07:57we can't be sure.
07:58But the very centre is generally described as a singularity.
08:02This is a point of infinite density, with zero volume, where all absorbed matter will
08:07eventually end up.
08:08In this particular what-if scenario, it's what skyscrapers and trees, cars and books,
08:14rocks, water, people, and animals are all destined for.
08:18It's where the past, present, and the future all bends and blurs into one, until it's
08:24as though none of it ever existed at all.
08:27What do you think?
08:28Is there anything we missed?
08:29Let us know in the comments, check out these other clips from Unveiled, and make sure you
08:33subscribe and ring the bell for our latest content.

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