• last year
Our universe is racing toward its destruction, right now. But how exactly will it end?

Category

📺
TV
Transcript
00:00 (music)
00:04 What if all the stars disappeared tomorrow?
00:08 Together with all the planets,
00:10 solar systems and galaxies?
00:12 What would be left of the Universe
00:14 if it suddenly collapsed?
00:16 What could make it restart its cosmic cycle
00:19 all over again?
00:20 And how exactly could the entire Universe break apart?
00:25 This is WHAT IF,
00:26 and here's what would happen
00:28 if the Universe ended tomorrow.
00:32 Some 50 million years from now,
00:34 the Martian moon Phobos
00:35 will slam into Mars and shatter to pieces.
00:38 In 100 million years,
00:40 Earth will likely get hit by an asteroid
00:42 the size of the one that caused
00:43 all the dinosaurs to go extinct.
00:46 In about 1.5 billion years,
00:48 the Sun will become so luminous
00:50 that it will force the habitable zone
00:52 to move outwards,
00:53 leaving what's left of Earth to get crispy.
00:56 Everything will eventually come to an end,
00:59 even our almost 14 billion-year-old Universe.
01:02 What would it be like to witness
01:04 the epic end of the cosmos?
01:09 Don't get too comfy.
01:09 The end of the Universe
01:11 would mean the end of everything in it.
01:13 Two trillion galaxies
01:14 that we can observe from Earth
01:16 filled with a tremendous amount of everything,
01:18 from enormous gas giants
01:20 to weird-shaped asteroids.
01:22 Everything would be gone,
01:24 including you and whoever else is out there.
01:27 But your last moments could be very different,
01:30 depending on how the Universe shut down.
01:32 Here are three ways it might happen.
01:36 One possibility is it might get really chilly.
01:40 The Universe is expanding.
01:42 Galaxies are moving away from each other
01:44 at an ever-increasing rate,
01:46 despite the attempts of gravity
01:47 to pull them back together.
01:49 That's because a theoretical force
01:51 called dark energy
01:53 is opposing the force of gravity.
01:55 If one day this dark energy
01:57 pulled a little too hard,
01:58 the pieces of raw material
02:00 needed for star formation
02:01 would become too far away from each other.
02:04 All the existing stars
02:05 would eventually run out of fuel,
02:07 and there would be no new ones to replace them.
02:09 It would get very dark and very cold.
02:13 Once the temperature reached absolute zero,
02:15 nothing would be able to move,
02:16 not a single atom.
02:18 The Universe would become
02:19 the most boring, static place,
02:22 and would probably remain
02:23 an endless void forever.
02:26 I bet you were hoping for a more spectacular ending
02:28 to this story.
02:29 So let's add more action
02:30 with the Big Rip.
02:33 If the dark energy became so intense
02:35 that it was able to nullify
02:36 the force of gravity altogether,
02:38 it would rip the Universe apart.
02:41 It would start with the galaxies,
02:42 tearing them down one by one.
02:45 Black holes would be the next to disintegrate,
02:48 followed by stars,
02:49 planets,
02:50 asteroids.
02:52 As the expansion of the Universe ramped up,
02:54 every form of matter
02:55 would collapse on itself
02:57 and decay into radiation.
02:59 That, of course, includes you.
03:02 The Universe would end up
03:04 full of single particles.
03:06 Would it ever come together after its death?
03:09 Let's try our luck with the Big Crunch Theory.
03:13 If the force of gravity fought back
03:15 hard enough to overthrow the dark energy,
03:17 the Universe would stop expanding.
03:19 It would shrink back instead.
03:22 Planets would collide with other planets.
03:24 The stars would slam into each other.
03:27 Galaxies would merge together.
03:30 Earth wouldn't be able to dodge
03:31 all the space matter for too long.
03:33 The Universe would compress
03:35 into a very dense singularity,
03:38 just the way it was before the Big Bang
03:39 began spewing out galaxies.
03:42 From that singularity,
03:44 it could make a fresh cosmic start,
03:46 with new planets,
03:48 new stars,
03:49 new life forms.
03:52 One way or another,
03:53 the Universe and everything in it will end.
03:55 But it won't happen in just one day.
03:58 We still have time to become
03:59 a more advanced civilization,
04:01 and maybe even find a cozy exoplanet to settle on.
04:05 But that's a story for another WHAT IF.
04:08 ♪ ♪
04:13 (thunder)