The Impenetrable Barrier Trapping Us in the Solar System

[00:00] Now available on the kurzgesagt Shop. Nobody alive today will. Locked in by an invisible barrier, impossible  to overcome for carbon based animals like us.

[00:20] And not just us – there may be millions  of alien civilizations in the universe, none of them ever able to venture  into deep space in a meaningful way. Ok but how can this be? We've made  countless videos imagining how the

[00:35] exploration of the galaxy and beyond  should just be a question of time. Sort of mandatory for  civilizations at a certain point. But there is a catch: We are pushing  up against fundamental physics.

[00:47] What is this barrier, made of dust and  nothingness? And why is it so hard to overcome? We Don’t Either. Conceptualizing the size of space  is impossible for our ape brains

[01:03] that evolved to understand distances like  “right here” and “over the next hill”. Space is so absurdly huge that we just  check out and just hear “very far”. “Very far” and “A million times very  far” feels the same but it is not.

[01:21] To help our brains, let us start with  what makes us cross distances: speed. The fastest a human ever traveled in  space were Astronauts at 40,000 km/h, Not bad, but way too slow.

[01:38] The fastest thing humans have ever  built by far is the Parker Solar Probe, hurling around the gravity well of Venus,  accelerating to get closer to the sun. the probe is shooting through space  at a breathtaking 635,000 km/h.

[01:56] or to cover the distance  from Earth to the moon in 36. So let’s pretend we had a spaceship that fast,  with a human crew ready to explore the universe!

[02:08] but our new spaceship covers the  distance in just two weeks! Pretty good! The next stop is Pluto which we will  reach after about a year – ok much longer,

[02:21] but still ok! It only takes two  more years to pass the heliopause and one more to pass Voyager II, which  traveled over 50 years to get this far. The next stop is the end of the Oort cloud,

[02:34] the true edge of the solar system where open  space begins! We reach it in… 2,500 years. Not only did we travel for the amount of  time it took to get from the founding of

[02:48] the Roman Republic to the present  day, there is NOTHING out here. The barrier of nothingness that might  trap us in the solar system forever.

[03:00] There is a place that is very far away but  with human ingenuity and billions of dollars we can get there! Then you zoom out one  more time and all hope leaves your body. Why don’t we just go faster?

[03:17] Well we don’t know of a non-magic way to travel  faster than light, teleport or freeze people. But things like a propulsion system  that uses nuclear fusion or antimatter, are in the realm of the physically possible.

[03:34] Ignoring the technical details and various  problems that these energy sources have, can get a spaceship to fly at  around 20% the speed of light! Which is extremely fast – 60,000 kilometers  per second, 216 million kilometers per hour.

[03:52] Fast enough to reach the edge of  the solar system in just 3.5 days Alpha Centauri, the closest star system to  our own in 20 years!

[04:04] We don’t have internet! Wait, what? Just kidding – but our sponsor Saily can  help YOU with that problem while travelling.

[04:17] Saily is the eSIM service app  from the creators of NordVPN. You can choose from a wide range of  affordable eSIM plans for over 200 destinations, so you’ll never be without  an internet connection while traveling. 

[04:29] Just download the app, pick a data  plan, use the code “kurzgesagt” for a 15% discount on your first data  package, and install the eSIM in advance. It’ll activate automatically when you arrive,  and you can start browsing right away.

[04:42] You can also use Saily to feel like a  local – it now comes with an app-based phone number for voice calls and  SMS that stays the same everywhere. Perfect for local apps, shops and travel  companions – and to keep your real number private.

[04:57] With just one app download, you’ve solved your  internet problem while traveling once and for all, Download Saily and use the code “kurzgesagt”  at checkout or go to saily.com/kurzgesagt

[05:12] go back to solving our trickier travel problems. Everything should be sorted out now, right?  Well..there is only one small issue:

[05:24] Space Hates You: The Barrier of Dust Unfortunately we will run into  a few obstacles on the way. Because while space is very  empty, it is not actually empty.

[05:38] There are energetic particles, gas,  dust and things bigger than dust. if you are going really fast and smash  into something, you have a huge problem.

[05:50] this is true even if the thing you  are smashing into is just an atom. An individual iron atom that  hits your spaceship at this speed Over time its hull would be riddled with  microscopic bullet holes, which is not great.

[06:09] Of course our engineers knew this  and created a shield for our ship. A sort of protective sail that absorbs or at  least slows down most molecules we smash into. there are things floating around in  space that are larger than atoms.

[06:24] Running into a single grain of dust at 20% the  speed of light is like running into a grenade, causing a tiny detonation as the dust explosively  evaporates, grinding away our protective shield. Like a small rock, the size of a golf ball.

[06:41] the energy of the nuclear bomb  that was dropped over Hiroshima. Atoms, dust and pebbles are dangerous enough.

[06:54] We might have reached our natural  speed limit here – besides the fact all of the damaging effects of hitting stuff  floating around in the void get much worse fast.

[07:07] our spaceship should be able to survive traveling  through space at roughly 20% the speed of light long enough to get to at least nearby  stars in a reasonable amount of time!

[07:21] Almost Everything in Space that's Close is Super Lame The first proper target outside the solar  system is the Alpha Centauri System.

[07:33] more realistic ship but only 20 years  with our super fast fictional ship! So let’s cram a few unlucky humans into  a tiny box for 20 years and send them

[07:46] on their way and assume they somehow  make it without murdering each other! People around the globe gather together and  hold their breath, eager to listen to it:

[07:59] “We arrived! Alpha Centauri and its  planets are very pretty up close! Unfortunately they are all  super deadly and uninhabitable. But we are doing extremely cool astrophysics and  are learning a LOT, which is pretty exciting!

[08:13] We are getting kind of tired of freeze dried food  and desperately need new shows to watch though. The thing with space is that  almost all “close destinations”,

[08:25] if close means something different from  what it usually means, are pretty lame. Not from a scientific perspective of course!  It would be an absolute dream to have the privilege to set foot on foreign planets  and marvel at the wonders of our universe!

[08:39] But if 20% of the speed of light might be our  speed limit, and we give humans a realistic travel time of say, 40 years, we could reach  things that are up to 8 light years away. None of the targets remotely within this range,  within a human lifetime, may be worth traveling

[08:53] dozens of years in a tiny box, through one  of the deadliest environments imaginable. Our solar system is a bit unlucky in that regard,  we are in a relatively empty pocket of the galaxy. This might change in a few million years as we  move through the galaxy, and there might be small,

[09:08] localized star spanning civilizations  – we discussed this in another video. Let’s say that we could go much further, to any  of the stars within our stellar neighborhood, 0.02% of the milky way by the way.

[09:23] This tiny bubble is currently inhabited  by 34 stars, and 6 brown dwarfs. But one of them is actually the sun  and another one is Alpha Centauri A.

[09:37] planets that vary from deadly to super deadly. There are a few planets in the habitable zones  of their stars, where water can be liquid. But, Mars is also in the habitable  zone of the Sun and it is really bad.

[09:53] Even the planets that we think look most like  Earth, like GJ1061 d, come with no guarantees. Imagine traveling your entire  life and then arriving at a Mars. There are a few stars that  would be interesting targets

[10:10] and may have actual habitable planets – planets  with oceans and atmospheres that are breathable, which probably would mean that they have  some form of microbial life, if not more. It would be extremely interesting and  definitely worth it to check them out!

[10:24] But they could be dozens, if not  thousands of light years away. even at a large fraction of the speed of light. technologically way more advanced than us  and very motivated could find solutions.

[10:42] Maybe they have solved biological aging  and a travel time of a few hundred years Maybe they could send AI spaceships with  embryos or some version of that into space. to make sure they don’t choose star  systems that are deadly and empty.

[10:59] But it is still hard to imagine without  real science fiction technology, how they could build and  sustain a connected civilization. The longer you think about deep  space, the less it makes sense.

[11:12] The distances are too vast, there is a  deadly speed limit and even if we could solve these issues almost all destinations even  remotely reachable may not be worth the trip. Space is the greatest challenge  humanity will ever face.

[11:27] Rockets, computers and even nuclear fusion  reactors are hopelessly underpowered. We need technology that is  overwhelmingly transformative.

[11:39] Something as wild to us as flying to the  moon would have been to a hunter gatherer. We genuinely don’t know. there are few things that make you look dumber  than predicting the future of technology.

[11:55] In 1903 the New York Times published an  editorial, "Flying Machines Which Do Not Fly” that   confidently predicted it would take humans one  to ten million years to achieve powered flight. 69 days later the first  successful flight happened.

[12:11] So we really hope this video will seem as  dumb as this article in a hundred years. And there is another option entirely – maybe our  thinking about all this is just completely wrong.

[12:25] Maybe the future is not out there, but deep  down – but we’ll explore that in another video… The latest LTD. Edition Pin is here, continuing the Cosmic Time Collection.

[12:39] But this device offers you a rare  glimpse into the end of the Universe. Spoiler: one by one, all the stars will die,  until everything is swallowed by darkness.

[12:51] Wear this animated, lenticular pin as  a reminder that you exist right now, with stars and light and there  is so much left to discover.

[13:03] You are exactly where you belong  in cosmic time and the Universe. Only 10,000 Vanishing Stars Pins exist,  and each one is individually numbered. Add it to your collection, or start  a new one while supplies last.

[13:16] And while humanity may still be  confined to a tiny corner of the cosmos,   To celebrate these milestones, we created  our Cosmic Milestones Poster Collection, featuring the first Moon landing, the Mars  rover Curiosity, and the Wilson Observatory,

[13:32] Get your favorite, or better, all of  them and create a gallery wall that will inspire you every day and remind  you of what humanity is capable of.

[13:44] – get your special piece of  kurzgesagt and the cosmos now.