PBS Space Time
PBS Space Time
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Could We Terraform Mars?
Views 444K6 days ago
The Quantum Internet
Views 411K2 months ago
The Cosmic Dark Ages
Views 452K4 months ago
Will You Travel to Space?
Views 204K6 months ago
The Crisis in Cosmology
Views 663K8 months ago
'Oumuamua Is Not Aliens
Views 569K10 months ago
Why String Theory is Right
Views 974K10 months ago
Will We Ever Find Alien Life?
Views 770K11 months ago
Hawking Radiation
Views 650KYear ago
Space Time VR
Views 95KYear ago
The Vacuum Catastrophe
Views 760KYear ago
White Holes | Space Time
Views 1.9M2 years ago
Dark Flow | Space Time
Views 887K2 years ago
The Real Star Wars
Views 320K2 years ago


  • J
    J 7 minutes ago

    You could say string theory comes with a lot of strings attached.

  • Matt S
    Matt S 25 minutes ago

    So what would need to happen in order to prove string theory or loop quantum gravity?

  • Raaa Dunk
    Raaa Dunk 33 minutes ago

    Ohhh I get it 2 + 2 = infinity divided by space time, ah shucks, sorry guys brain.exe stopped working again.

  • Tudor Baldean
    Tudor Baldean Hour ago

    42, the answer to everything

  • Tachsman
    Tachsman Hour ago

    Having visited the inside of a black hole in my younger days... this is all wrong.

  • Mortum Rex
    Mortum Rex Hour ago

    Thanks for blowing away all the hot air around human life on Mars. I like Musk, but he bloody well knows terraforming it is a pipe dream and still goes on about it anyway.

  • Russell Popham
    Russell Popham Hour ago

    Self-replicating molecular nanobots. that's the answer to converting the entire surface of Mars through The rate at which such theoretically machines could do this is amazingly short, although the limitation on speed being the energy needed to do so.

  • Joseph Dumornay
    Joseph Dumornay Hour ago

    Why not talk about underground canals , idk if mars has mars quakes from cooling or something but can you dig deep enough to the pressure u need and try and make cities underground

  • Pan Darius Kairos

    Why do people assume we'll need to breathe at all in the future? 🤔🤨

  • Antti Kalpio
    Antti Kalpio 2 hours ago

    Is there a reason we don’t build reactors deep underground where they could be isolated and cooling water could be directed to the reactor using gravity, which doesn’t require working pumps?

  • Slavik Cher
    Slavik Cher 2 hours ago

    Gravity, 4th dimensional vaccum.

  • Bear
    Bear 2 hours ago

    Universe is isotropic and homogeneous

  • Gerard Schafhäutle
    Gerard Schafhäutle 2 hours ago

    Orbiting Rainbows seeing everything across the cosmos at will? Name suggestion: Project BIFROST

  • Marko Oli
    Marko Oli 2 hours ago

    so nasa hire this asshole to keeps they lies alive…. fuck u u fucking clown

  • Connor M
    Connor M 2 hours ago

    Only Venus is truly terraformable, via the use of floating platforms housing genetically engineered organisms that can use sunlight to reduce the CO2 and sulphuric, to decrease the greenhouse effect and eventually lower the density of the atmosphere at ground level.

  • TWSTF 8
    TWSTF 8 2 hours ago

    Of COURSE he pronounces it; "Koyper Belt," lol 😂

  • kking1777
    kking1777 2 hours ago

    Mars used to have a vibrant atmosphere when it's magnetosphere was strong but it ended up losing its magnetism which got rid of the protection it had from solor weather which ended up stripping Mars of its atmosphere and water.. So no it could never be terraform without remagnetizing Mars

  • dpsamu2000
    dpsamu2000 2 hours ago

    Sorry, all those methods are already obsolete. The potential of computer technology has already exceeded the wait time for all of those ideas. Not only is computer technology the best funded, and fastest growing technology that can be used for spaceflight but the rest of the hardware need to make it work for spaceflight is already available. In fact we can even start doing equipment manufacturer choices, time of flight estimates, and cost estimate. Comparison to the cost of many of the obsolete methods mentioned show that even the most economical method is billions of times more expensive. The anti matter fuel source is the least economical being that it would take all the matter in the visible universe burned in a fusion reactor to produce enough antimatter the way we currently produce it to fuel one flight. The hardware for computer based spaceflight are well known given the computer technology to make the needed core technology. Easily conceivable for computer spacecraft smaller than a cell phone are foreseeable. The cost of an electric catapult for launch is cost dependent merely on the weight, and robustness of the spacecraft. A device capable of taking 10,000 G would only have to be 3000 miles long to get .01c. We already have GPS guided artillery shells that can withstand that for the short time it takes the artillery to launch the shell. We should start making a study of the animals that will be our representative astronauts to be the recipients of our mind data transfers. Probably crustation or fish eggs that can survive the G force in a dry state. That would be the key limit on acceleration of the launcher, and therefore the launcher cost. Then guided evolution to yield better recipients. That is to colonize planets that don't already have reasonably evolved life. We could begin the colonization launches using about 10 percent of US GDP within 20 years. the shps could begin arriving on extra solar planets, depending on launch exigencies, in as little as 30 years from launch. no later than 400 years from launch. The launcher is, of course, reusable, and targetable. Given continuous launches of 1 a day, and a spread of targets we could have new colonies landing every day after the first ones start landing. I propose smart people like you stop fantasizing about 1950s era sci fi star trek, and star wars fantasies which are merely extensions of thinking from the 1690s era of sail exploration. Get your heads in the game where it really can be done in 21st century technology, and thinking.

  • Titanic Truths
    Titanic Truths 2 hours ago

    Theoretically. If we used nuclear weapons, we could make Mars habitable. It may soumd weird, but stick with me. If we detonated a series of nukes at a certain altitude in Mars atmosphere, we could use the heat and radiation to create a protective barrier similar to the radiation belt here on earth. However, too low and you render the planet useless for good. Too high, and it does nothing. Basically wasting time, money and resources.

    • John theux
      John theux 2 hours ago

      A brand new atmosphere will last for about 500 millions years so the lack of magnetosphere is not an issue.

  • orlandothx
    orlandothx 2 hours ago

    Miles per hour??? If you intend to reach stars, first you need first at least to use metric system, seriously.

  • D3w10n
    D3w10n 3 hours ago

    Christ, video barely began and you start with a suicide joke? XD

  • Altered Beast
    Altered Beast 3 hours ago

    Could we build a biodomes? I like the Red faction reference btw

  • itsasin1969
    itsasin1969 3 hours ago

    All I know is,, I really want to have your baby, Oh wait,, I'm a guy.

  • michael bisin
    michael bisin 4 hours ago

    Who came here, after seeing the equation on senku's clothes on Dr.Stone?

  • Pierre Villemaire-Brooks

    Our nukes are most likely what may have made us noticeable by our cosmic neighbours … and if we are looking for a reply it may already have been laid at our feet , literally (aka crop circles)

  • Stormy Fairweather
    Stormy Fairweather 4 hours ago

    Nothing is impossible. So when nothing occurs, SOMETHING must happen. Hence, the universe.

  • Mando H
    Mando H 4 hours ago

    You're the parasite that terraforms earth! For future earthling!

  • SlyPearTree
    SlyPearTree 4 hours ago

    It would be better if we have self sustaining extra terrestrial colonies before we try to have an extrasolar one. If we have no choice then we need to launch what we can but this only mean that we have to try to have extraterrestrial colonies within the solar system as soon as possible so we can learn what their needs are.

  • Alan Scott
    Alan Scott 4 hours ago

    Retard. Fucks would do anything for money. If he says anything truthful he would be demonetized.

  • Pierre Villemaire-Brooks

    Mind Blown @.@

  • Johm Smith
    Johm Smith 4 hours ago

    Theres no such thing as gravity the phenomenon of gravity obviously is real but this is retarded

  • Brendon-Kayne Albertze

    "certain crowd"?

  • Charlie Angkor
    Charlie Angkor 4 hours ago

    how can the host talk about such theories in several videos without going completely nuts is beyond my understanding.

  • Charlie Angkor
    Charlie Angkor 4 hours ago

    If we cannot conform our theory to the universe, couldn't we try to conform our universe to our theory instead?

  • KensCrazyThoughts
    KensCrazyThoughts 4 hours ago

    Why not live underground and have The Martian surface as our protection.. It would be less costly to just dig up giant rooms underground. Meanwhile acquiring natural resources in the process

  • Anders Eriksson
    Anders Eriksson 4 hours ago

    This is just mind blowing..

  • Harry Cole
    Harry Cole 4 hours ago

    Creating a black hole inside of the space ship… seems like we forgot what those things do for a living.

  • The Screaming Zombie

    Why dont we live on the sun... No seriously, although the sun is very hot there are places on The sun that are freezing and they are called sun spots. One sunspot can get up to -400 degrees or something around there

  • Charlie Angkor
    Charlie Angkor 4 hours ago

    sufficiently advanced technology is indistinguishable from magic. Sufficiently advanced theory is indistinguishable from schizophrenia.

  • Charlie Angkor
    Charlie Angkor 5 hours ago

    19th century: throw in some extra cogs and levers. 20th century: throw in some more dimensions, infinities and singularities

  • Charlie Angkor
    Charlie Angkor 5 hours ago

    setup a generator of physicist technobabble to generate random theories. test them one by one. sooner or later, you may hit a functioning Grand Unified Theory of Everything. Like: the renormalization on gravitons along 17-dimensional soliton dilaton string in supersymmetry of meson hadron boson quarks renormalize the time dilation in 5-dimensional electrogravity spin field dual to holographic projection of a ringularity in a weakly interacting Minkowski time-space

  • Easy Cheesy
    Easy Cheesy 5 hours ago

    Yep that's it America.. you fucked the whole planet but why not stop there.... Why not the whole universe!

  • Charlie Angkor
    Charlie Angkor 5 hours ago

    We can't build a phone app that doesnt crash or freeze, but lets build a simulator for the whole universe?

  • Tachsman
    Tachsman 5 hours ago

    Case in point: As Einstein stated, "If you can't explain it simply, you don't understand it well enough." This guy is Lost in Space.

  • Charlie Angkor
    Charlie Angkor 5 hours ago

    Science is a way how to transform our perceptual reality into an insolvable mathematical impasse.

  • Charlie Angkor
    Charlie Angkor 5 hours ago

    could a string be the same thing as the ringularity inside a rotating black hole?

  • Charlie Angkor
    Charlie Angkor 5 hours ago

    could we fix the mess if we work in 1800052300061123579741246996212589076312900000000000000000001 dimensions and divide all equations by infinity 18952124100875315 times?

  • Charlie Angkor
    Charlie Angkor 5 hours ago

    can a string carry several particles at the same time?

  • Charlie Angkor
    Charlie Angkor 5 hours ago

    are there virtual strings, like virtual particles?

  • Charlie Angkor
    Charlie Angkor 5 hours ago

    what happens to a string when it falls into the singularity of the black hole?

  • Charlie Angkor
    Charlie Angkor 5 hours ago

    are there antistrings?

  • Charlie Angkor
    Charlie Angkor 5 hours ago

    do the strings have spin?

  • Charlie Angkor
    Charlie Angkor 5 hours ago

    can knots be tied on the strings?

  • Charlie Angkor
    Charlie Angkor 5 hours ago

    what is the size of the coiled dimension? cm? mm? um? nm? fm? am?

  • Charlie Angkor
    Charlie Angkor 5 hours ago

    how many MeV mass does the graviton in string theory have?

  • Charlie Angkor
    Charlie Angkor 5 hours ago

    why dont they just add a corrective term to the equations or divide by some infinities to fix the mess between gravity and quantum mechanics? they do this all the time

  • Daniel Rodriguez
    Daniel Rodriguez 5 hours ago

    What's reality is Miller time🍺🍺🍺🍺

  • Charlie Angkor
    Charlie Angkor 5 hours ago

    how fast do strings move?

  • Charlie Angkor
    Charlie Angkor 5 hours ago

    do string posess electrical charge?

  • Charlie Angkor
    Charlie Angkor 5 hours ago

    do strings interact with electrical field?

  • Charlie Angkor
    Charlie Angkor 5 hours ago

    what is the speed of the waves along the string?

  • Charlie Angkor
    Charlie Angkor 5 hours ago

    do the strings change length?

  • Charlie Angkor
    Charlie Angkor 5 hours ago

    how long are the strings?

  • Charlie Angkor
    Charlie Angkor 5 hours ago

    are all strings the same or are there various types? if yes how many types?

  • Charlie Angkor
    Charlie Angkor 5 hours ago

    do strings bounce when they collide, or do they pass through each other like photons?

  • Charlie Angkor
    Charlie Angkor 5 hours ago

    can string split or merge?

  • Charlie Angkor
    Charlie Angkor 5 hours ago

    how long does a string live before it disappears? or is it eternal?

  • Charlie Angkor
    Charlie Angkor 5 hours ago

    how many strings are there per cubic meter?

  • Charlie Angkor
    Charlie Angkor 5 hours ago

    Einstein discovered relativity because he was not afraid of crazy ideas like shrinking objects or time slowing down. Maybe we just have to stop being afraid of the idea that all particles are little black holes. Or that the laws of physics are internally logically inconsistent. Take the craziest theories and the craziest one will probably be the true one.

  • Charlie Angkor
    Charlie Angkor 5 hours ago

    What if we let a string of satellites enter a black hole? the satellite under event horizon transmits to the one on the event horizon, it will be received redshifted but retransmitted again to the satellite above event horizon. will this work to get information out what the black hole looks like inside?

  • Bill McQ
    Bill McQ 5 hours ago


  • CarmineFragione
    CarmineFragione 5 hours ago

    The Universe may last a long time but it is not forever, and so also a Dream is not forever, but while the time permits, each is a great mystery , a world appears in a field of dreams, and what then is the difference ? God dreams and worlds appear, and so you were made in the image of God and you get your own time to dream. The nature of a dream is a parable of a temporal world, while it lasts , it is persistently saying it is real, but when it is over, of course it cannot boast any further. Alternate states of being, there is a Mind, then there is a dream producing matter to it, and then within the matter a secondary reflection of the first cause, a Mind appears , and another world appears again within that substructure, like a box inside a box, inside a box, the worlds keep regressing , with layers of ghost like minds designing , like an Italian Layer Cake. ...

  • Toughen Up, Fluffy
    Toughen Up, Fluffy 6 hours ago

    OK, now show the mathematics.

  • Todayi1itall
    Todayi1itall 6 hours ago

    Musk doesn't want to go to Mars himself. On the way he's going to get you to mine asteroids for his company's profit.

  • Todayi1itall
    Todayi1itall 6 hours ago

    Terraform the Sahara Desert first. I know how, have Musk contact me.

  • Toughen Up, Fluffy
    Toughen Up, Fluffy 6 hours ago

    How can you be in two places at once when you're not anywhere at all?-Firesign Theater

  • MTheory
    MTheory 6 hours ago

    stop acting like fucking idiots and let's sustain the planet we are already on we can start by exiting ignorance like TRUMP

  • kevin clsyton
    kevin clsyton 6 hours ago

    JWST seems very scary to me.only 9ne thing needs to go wrong and its scrap..we all remembered HUBBLE ffs NASA seem to fuck these big project up..really hope it all goes well tho..it will definitely be a game changer

  • Jim Gibbons
    Jim Gibbons 7 hours ago

    Neither. Just continue the search for intelligent life on Earth.

  • M. Hall
    M. Hall 7 hours ago


  • Zangief The Red
    Zangief The Red 7 hours ago


  • Jaded Cynic
    Jaded Cynic 7 hours ago

    Until we fix our deserts mars is a stupid idea. Get on it NASA. You can fly around in a vaccuum later.

  • TheIronAntelope
    TheIronAntelope 7 hours ago

    What if the big bang was a super massive white hole spewing out everything that will ever be swallowed by black holes? That way all matter and energy in the universe would be caught in an infinite time loop.

  • Ian Alvord
    Ian Alvord 7 hours ago

    "ok, cool story bro" At least I understood that part!

  • Aaron Cashen
    Aaron Cashen 8 hours ago

    Could the 10,000+ comets potentially have enough kinetic energy to sufficiently heat the core of Mars enough to restart the dynamo? Something proportional in scale to the hypothesized Theia impact on Earth.

    • John theux
      John theux 2 hours ago

      A brand new atmosphere will last for about 500 millions years so the lack of magnetosphere is not an issue.

  • Sasukes Duck Butt Hair

    "ShoUlD We CoLoNiZE VeNus InsTeAd Of mArs?" What are you smoking crystal *METH* ?! We would NEVER survive there.

  • Will nelson
    Will nelson 8 hours ago


  • mcarp555
    mcarp555 8 hours ago

    1. What's to stop a terraformed atmosphere from being lost to space because of the weak gravity of Mars? That's part of what happened originally. 2. Why not build underground cities? You have better protection from cosmic rays and impacts.

    • John theux
      John theux 2 hours ago

      A brand new atmosphere will last for about 500 millions years so the lack of magnetosphere is not an issue.

  • MJ
    MJ 8 hours ago

    Hell no

  • Bobson Bobby
    Bobson Bobby 8 hours ago

    If the universe is flat. And if we can deduce where the flatness goes, then why dont we ever go UP? Obviously up is relative to position, but if you consider the entire universe as the system then up would have a definition IF its flat. And, I do know that that distance is still probably huge. Just a thought.

  • Mohammad M
    Mohammad M 8 hours ago

    If you decide to become an astrophysicist, should you minor in a second degree or just astrophysics?

  • El Merelles
    El Merelles 9 hours ago

    Yep, solid core, no magnetosphere, no life. Terraform Venus? Best chance for earth is a human population reduction, you know it’s true.

  • Mario Legend
    Mario Legend 9 hours ago

    What if gravity is a wave that affects the motion of photons through space time your all a bunch of retards

  • Dan Kuchar
    Dan Kuchar 9 hours ago

    No one is going to live on Mars any time soon, for the same reason people aren't moving to Antarctica; it's cold, it's miserable, and there's nothing to be gained by going there. If someone finds a financial or political reason to go, then people will flock there. Sorry Elon.

  • Elisha North
    Elisha North 9 hours ago

    7:26 “Kilometers/m^3” Some strange dimensions there, haha.

  • Greenie5000
    Greenie5000 9 hours ago

    Wow! Peter Dinklage has grown!

  • Brandon Hall
    Brandon Hall 9 hours ago

    Earth is flat brotha

  • Brandon Hall
    Brandon Hall 9 hours ago


  • wulphstein
    wulphstein 9 hours ago

    Maybe spacetime geometry is a place to pur quantum states, which are a place to put particles.

  • Sosostupid
    Sosostupid 9 hours ago

    This “white hole” , rather the mathematical description, is still describing the same black hole- only from the “inside” looking “out”. When you are already beyond the event horizon, when you look back at the event horizon, all matter, including light, is now escaping- moving Outward from the Event. It’s just so logical. We are all such narcissists, that we so often just completely dismiss Perspective. Perspective, in actuality, is the single Most Important variable in ANY and all equations (problems) we encounter. Try taking perspective into consideration next time you and your lover are engaged in domestic warfare...it’ll help.