The Most TERRIFYING Places in the Universe in 14 minutes

[00:00:00]Have you ever had a recurring nightmare where a pulsar beam hits you 716 times a second or a black hole stretches you into a mile of meat before you even reach the event horizon?

[00:00:10]No? Just me?

[00:00:12]What? Oh my god, why are we in space?

[00:00:15]Good morning, Billy. We're going on a trip to visit the most terrifying places in the universe. 10 stops, 10 ways the universe gets progressively worse.

[00:00:22]You're welcome.

[00:00:26]Black holes are some of the craziest things in the entire universe. It's been half a century and the best image you have of one is this. You see, black holes are not special because they're some type of cosmic vacuum. Every mass in the universe exerts a gravitational pull. That's just gravity. The sun pulls on Earth. Earth pulls on you. A black hole is what happens when so much mass is compressed into so small a space that the escape velocity at its event horizon exceeds the speed of light. Meaning, nothing that crosses the event horizon has ever returned. This one is a stellar mass black hole between 5 and 30 times the mass of our sun compressed to roughly 37 miles across. At its event horizon, the gravitational pull exceeds Earth's by more than 100,000 times. The supermassive ones at galactic centers reach into the trillions of Gs. You won't be approaching one of those today.

[00:01:14]A small one's sufficient. As you descend, the gravitational pull on your feet becomes meaningfully stronger than the pull on your head. The tidal force stretches you. Your feet accelerate thousands of times faster than your skull. Tissue, bone, everything pulls apart in a process called spaghettification.

[00:01:31]He'll be fine. Technically.

[00:01:37]The Boötes void. Approximately 330 million light-years of almost nothing.

[00:01:42]In a universe that's normally dense with galaxies, this region simply is not. The full observable universe contains roughly 2 trillion galaxies. This region contains 60. There are two theories on why this exists. First, gravity, being the universe's ultimate matchmaker, gradually pulls matter together over billions of years. Galaxies cluster, and the spaces between them grow emptier.

[00:02:04]Neglect any region long enough, and you get this. Second theory, the Bootes Void isn't empty. It contains civilizations so advanced they've harvested the energy of entire galaxies, making themselves invisible to any instrument you have.

[00:02:18]This would be a type three civilization on the Kardashev scale, able to manipulate galactic-scale energy. This civilization would look like a civilization. They would look like nothing, at least in the visible spectrum. However, given that we're here, and no one from said civilization has come to say hi, they are either incredibly rude or don't exist. Despite being a void in space, the Bootes still contains around 60 galaxies, and probably more than a billion stars in between. It's a reminder that the universe can be as suspiciously patchy as a lonely middle-aged man insisting his beard is fully coming in. But don't worry, Billy. You have me now. This is the most alone you'll ever feel.

[00:02:56]Billy?

[00:02:57]Billy!

[00:03:01]Before we discuss what this does to you, it needs to be born.

[00:03:04]Just fade to black, and it's lights out.

[00:03:07]Gravity wins, no room left for doubt.

[00:03:09]The core gives in, atoms collapse tight, protons and electrons stop their endless fight. They merge into neutrons dense to the core. A neutron star's born, but wait, there's more. Born spinning so fast it would make your head spin, but the field pumps the brakes, a few seconds to win. The weakest rotation of any neutron star, yet somehow one of the deadliest things that there are. The magnetic field lines, already wound tight, squeezed to a quadrillion gauss, an impossible sight. A titan that's forged from the embers of a star, behold what's born, a magnetar.

[00:03:40]>> [applause] >> Earth's magnetic field reaches about half a gauss. A typical neutron star produces around a trillion. A magnetar, a quadrillion. That's a thousand times stronger than a regular neutron star compressed into an object the size of a city. At that field strength, atoms don't behave normally. The electrons in your body get pulled free from their nuclei before any other process gets a chance to take you out first.

[00:04:02]Your body becomes entirely positively charged. If the magnetic field doesn't do it, the radiation will cook you. If the radiation doesn't finish you, the surface gravity, 200 billion times Earth's, flattens you to approximately one atom's thickness.

[00:04:17]I stood at roughly this distance from one once. The field has a particular texture at the boundary layer. You can feel the exact moment chemistry stops being chemistry.

[00:04:30]The small one used to be a star like your sun. It burned through its fuel, shed its outer layers, and collapsed into a dense Earth-size remnant called a white dwarf. So, it's roughly the size of a planet with about 100,000 times Earth's surface gravity. The large one beside it has since evolved into a red giant. The outer layers expand dramatically as it ages. In this case, the white dwarf's gravity is strong enough to pull some of that material toward itself, and it's been doing this for millions of years. But, there's a limit to how much mass a white dwarf can hold before the carbon in its core ignites. 1.4 times the mass of the sun.

[00:05:03]This is called the Chandrasekhar limit.

[00:05:05]When the white dwarf hits it, the entire star detonates simultaneously. Every part of it at once. The red giant survives, but is stripped and launched into the void at hundreds of miles per second. The relationship was always going to end this way. Sometimes the detonation is incomplete. The white dwarf doesn't fully destroy itself.

[00:05:23]Instead, it survives the explosion and gets ejected from the blast site.

[00:05:26]Scientists call these type 1A X supernovae. The zombie star just keeps going.

[00:05:34]So, the Milky Way is currently moving at 373 miles per second, but not aimlessly.

[00:05:40]It's moving toward something, an enormous concentration of mass approximately 150 to 250 million light-years away. It's called the Great Attractor. For decades, scientists have been racking their brains to figure out the reason behind this attraction.

[00:05:55]However, the dense wall of dust, gas, and stars from the Milky Way blocks visible light from this location from reaching Earth. Didn't expect your own galaxy to be such a troll, but hey, it hosts humans. Of course, it's going to have a few loose screws. Anyway, enter the 21st century and the smart humans are pretty much convinced it's an area exceeding a quadrillion solar masses with roughly 100,000 galaxies and significant quantities of dark matter tightly packed together. This gives it enough mass to pull almost anything from every little nook and cranny of the entire universe. And at the center of the Great Attractor is the Norma Cluster where most of the work's being done. But the worst part is that even the Great Attractor is moving towards a bigger supercluster called the Shapley Supercluster, which is around 10 to 50 times the mass of the Norma Cluster.

[00:06:41]Fear not though, cuz the rate at which the universe is expanding far exceeds the speed at which you're being shoved towards the cluster. At this point, the chances of you getting torn to shreds during the Big Rip are higher than Earth ever reaching anywhere near the Great Attractor.

[00:06:57]Now, before you flabbers are completely gasted, there's a thing out there so bright it makes entire galaxies look like a 3-W LED with the sheer intensity of light it produces in the cosmos. A quasar, also known as a quasi-stellar object, is one of, if not the most violently bright things in the universe.

[00:07:15]At the center of most large galaxies sits a supermassive black hole. Most of the time it sits quietly, but when it begins consuming surrounding gas, dust, and stars in sufficient quantity, it forms an accretion disk, superheated material spiraling inward before crossing the event horizon. During that slow and agonizing process, the disk heats to millions of degrees and radiates across the entire electromagnetic spectrum. The total output can exceed the brightness of an entire galaxy by a factor of a thousand.

[00:07:45]That is a quasar. The whole glowing accretion disk system blazing continuously, the brightest persistent objects in the observable universe. Some quasars also produce relativistic jets, mainly composed of electrons, protons, extremely twisted magnetic fields, and radiations flung across the cosmos at 99.9% the speed of light. If Earth gets hit by it, your ozone is cooked. The atmosphere becomes plasma and every living organism will get sterilized with 100% certainty.

[00:08:14]In essence, it's pretty safe to say that one whiff of it can cause mass extinction, which raises the question, is this yet another way humanity kicks the bucket? Unlikely. The nearest known quasar, Markarian 231, is 581 million light-years away. Its light left before complex multicellular life had fully established itself on Earth. By the time it reached you, it was just a faint reminder that somewhere out there a black hole was going absolutely feral 581 million years ago. So, yeah, sleep easy. I'm willing to bet my entire Steam library that a quasar jet will never hit Earth in your timeline.

[00:08:51]You're standing on a rogue planet, a full-size planet anywhere from Mercury to Jupiter in mass, drifting through interstellar space with no host star.

[00:08:59]There are a few ways this happens. Maybe during the formation of a solar system, the gravity went wacky for a moment and a planet got slingshotted at high speeds out of the system. Or a pocket of gas and dust in a stellar nursery collapses under its own gravity, the same process that makes stars, but never accumulates enough mass to ignite fusion. Instead, it became a cold and lonely planet that was never bound to anything. Stars nearby can also disrupt orbits, supernovas and dying stars can eject planets outright, and the list goes on.

[00:09:28]Estimates suggest there may be more rogue planets in the Milky Way than there are stars. Most are frozen with no source of heat beyond residual core warmth slowly bleeding into the void over billions of years. A A few, with the right internal geology, maintain enough heat for subsurface liquid water.

[00:09:44]There may be life on those ones, and that life would have evolved with no knowledge that any universe existed above it.

[00:09:53]The Boomerang Nebula, known to be one of the strangest objects ever found in space, it's widely considered to be the coldest natural place in the entire universe ever measured. Averaging temperatures about -272°C, it's literally colder than the cosmic microwave background, the radiation left behind by the Big Bang. You see, at the core of it all, a nebula is a dying star shedding its outer layers. But instead of just drifting away, the gas is expanding extremely fast at a rate of about 102 mph, fast enough that the gas cools dramatically as it expands outward. The same principle as a spray can. Pressurized gas releasing rapidly drops in temperature. At this scale, and running for thousands of years continuously, you get a region colder than any other natural process in the known universe has ever produced. It's a place where heat doesn't exist, and molecules are barely moving. Now look, I know it's called a Boomerang Nebula, so imagine my surprise when I found out this is what it really looked like.

[00:10:52]Disappointing.

[00:10:56]Next up in this cosmic journey is the edge of the universe. When you talk about the edge, it means the limit at which you can observe the universe. The universe is 13.8 billion years old. You might assume the observable limit is therefore 13.8 billion light-years in every direction. You would be wrong.

[00:11:14]Space itself has been expanding since the Big Bang. The oldest light you can observe left its source when the universe was only about 380,000 years old, long before galaxies even existed.

[00:11:25]That source has been moving away from you the entire time that light was traveling toward you. By the time it arrives, that region of space is now roughly 46 billion light-years away. So, the observable universe's full diameter is approximately 93 billion light-years.

[00:11:40]Beyond this point are galaxies that have already crossed your cosmic horizon.

[00:11:45]Their light, emitted today, will never reach you. They're already gone from your observable universe. So, there are stars out there that have already lived and died. There could be civilizations that rose and collapsed, entire cosmic histories that concluded before you had the technology to look, and none of their signals will ever close the distance. What you know so far is that the universe could be infinite.

[00:12:10]It's the end of our trip, and what better way to finish things off than by reminding you of the countless ways your own sun can end the Earth. The sun, 4.6 billion years old, one of the more stable, solitary, well-behaved stars in the galaxy. It's also going to be responsible for the end of life on Earth. It's just taking its time about it. The sun gets approximately 7 to 8% brighter every billion years. In roughly a billion years, this increase will trigger a runaway greenhouse effect on Earth. So, oceans will begin to evaporate, surface temperatures will climb past survivability. That's just the standard model of stellar evolution applied to your specific star. Before that, an extreme solar flare can disable unshielded electronics globally, knock out power grids, destroy satellites in orbit. The sun does this at random intervals, and you have no warning system currently capable of providing meaningful preparation time.

[00:13:02]And yet, even with all the threats posed, your sun is a strangely kind fellow, allowing life to carry on and even protecting it from threats. It's one of the very few stars that support life. Unlike 50% of stars who are in a committed relationship, the sun stays single, and Earth gets uniform heat and a stable gravitational pull. The sun doesn't flare violently or change its brightness into auto mode. It even goes an extra mile to protect the whole system by creating a heliosphere, a bubble that shields you from interstellar radiation. So, sure, it'll eventually swell up into a red giant and destroy Earth with the extreme heat and its expansion, but if humanity hasn't figured out how to get off-world by then, something else most likely has already taken you out. So, there you have it. 10 stops at the most terrifying things in the universe. Sweet dreams.

[00:13:56]>> The test subject is holding up well, better than expected.

[00:14:00]Though your assignments are starting to become more and more unhinged.

[00:14:05]And look, your next one is appearing on their screens now.