Space Time explores the outer reaches of space, the craziness of astrophysics, the possibilities of sci-fi, and anything else you can think of beyond Planet Earth with our astrophysicist host: Matthew O’Dowd.
Episodes released every Wednesday afternoon!
Matt O'Dowd spends his time studying the universe, especially really far-away things like quasars, super-massive black holes, and evolving galaxies. He uses telescopes in space to do it. Matt completed his Ph.D. at NASA's Space Telescope Science Institute, followed by work at the University of Melbourne and Columbia University. He's now a professor at the City University of New York's Lehman College and an Associate at the American Museum of Natural History's Hayden Planetarium.
Previous host Gabe Perez-Giz is an astrophysicist who studies black hole physics. He received his Ph.D. from Columbia University and also hosted PBS Infinite Series.

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  1. ranjeet singh

    So always Deal more kindly with one another, and to preserve and cherish the blue planet ,the only home we've ever known.That's here. That's home. That's us.....Carl sa

  2. Random Debris

    Q: Could there be a force that *increases* with distance?

  3. Greg G

    The last line in this video hit hard and dead center of our galactic responsibility not just our need to change here on earth, but to change as a whole.

  4. MrBradleyearl

    Thunderf00t is coming. just u wait.

  5. Boss Ross

    Maybe life started with the aliens in area 51

  6. Lazarus The adventurer

    So we are questioning why our overlords make the cosmologically constants the way they are ao that the simulation wont crash!!!

  7. Didivs Ivlianvs

    "That which I cannot create I do not understand." - Richard Feynman (One of his best quotes IMO)

  8. David ryan

    They'll probably talk to us once we stop killing each other over stupid reasons

  9. Force Fed Food

    The funny thing about you scientist is that you do go based off research and scientific equations that indeed make things reasonable and make sence. But when talking about life on other planets or galaxies that might be way superior to our own or greater species is a believable theory but the topic of an intelligent being far superior than we are that had something to do with our creation is unrealistic just because the subject is attached to religion.........humans continue to chase your tail.

  10. Robert Ellis

    To be honest, I see the Neanderthal.

  11. your mom

    "science" LOL

  12. Jesus

    I want aliens to be real so bad... But I do believe we may be alone... Intelligent-wise. There is more likely plants somewhere than beings like us. There's actually an equation for determining the probability of other life, though, it only uses speculation.

  13. in denial

    Suspicious Observers know the geomagnetic pole reversal is accelerating and won't take"a thousand years". Secondly , happening during a solar minimum can't be "GOOD NEWS" The magnetic link between earth and our sun could actually trigger g.s.min. There is probably a reason there are so many hand drawn and carved/engraved depictions on cave walls of Berckland filaments dating back to the last time humanity was faced with this. One has to wonder what our ancestors witnessed.....

  14. Jimmy Toetoe

    Wouldn't the black hole wipe out everything you pass in your travels?

  15. Jimmy Toetoe

    Ion propulsion?

  16. Andrew Dickson Lao

    Might as well study mars or other gas giants and their moons maybe there are some elements rarely appear in Earth other planet may have more of it than Earth

  17. AnimAlistic6

    Any relation to Peter Dinklage?

  18. Hethen Wells

    We must know what your dreams were before the universe got in your mind so strong, it's money that hates space

  19. Hethen Wells

    That's how we get a new project from creation, God will break off the old earth to make two new of the same one. You can't explain it if it's always just been an existing existance no matter what we should imagine some things as a warning instead of a far off site off of a man made machine

  20. bmobert

    Assuming we find zero life on Europa and that it is, in fact, very habitable, do we inject life into Europan oceans?

  21. Technically Difficulties

    Congratulations on your new job, Peter Dinklage! All jokes aside tho, great video.

  22. Trent Sullivan

    Unrelated to this video. But could the extra spatial dimensions predicted by string theory carry all of the missing mass that we call dark matter?

  23. David Siegel

    He doesn't look at historical levels of CO2, which have been much higher than today, in both hot and cold climates. If he did look at historical CO2 he would be skeptical of claims that CO2 is causing any warming now.

  24. Brad B

    why don't they make venus have an ice age, then wait till its habitable

  25. Ivan Korystin

    The problem with venus is resources. You can't dig there. So, no mining. All construction materials should be imported from space. And without mining in space, this does not seems possible.

  26. Dean Turner

    If the surface is separated from the core by a 100km ocean. Does this mean this surface and the core are likely to spin at different speeds.

  27. Hamid Aminirad

    Why doesn't a black hole transform its own mass entirely into light, but does it with mass particles, which are much furhter away, and which experience far less gravitational force than the particles in the center of the black hole?! And if it transforms them into light either, then where does the gravitational force of a black hole come from?! :-/ Black holes are the new age superstitions. Lies after lies, even in visible and facts-based science!? What a shame.

  28. SpaceWake walker

    There is a lack of understanding. This energy does not come from "nowhere". And you don't even need the eather to understand it. You can say It is EMF transformed. As if there is no EM from the core of the earth. You do acsess this energy when you wear wool clothes in dry air and getting static electrisity. If you really think it is "impossible" to acsess this energy. You must be extremley ignorant. The science is actualy very easy to understand. Please Educate your self. And study how the russians do it

  29. LONE Thomsong

    Nah multi verse is not possible If it is possible then when we die how? it become soul is one?😂😂😂.

  30. Sandy Manor

    When GOD put all in motion.. is when it all began.. I tend to grasp onto idea that TIME on the other hand had no significance or relevance until mankind came into play. GOD is outside of time as we humans know it, tho surely is REAL. How can we know HE exists? By seeking to learn HIS real truths. When one humbly seeks with full humility & real concern for self in finding truth, one will meet HIM. Science is facinating, GOD even more so... bec ause HE will reveal HIMSELF by 'lifting a veil' that we cant see thru, until we humbly choose to meet HIM. When its lifted, it's the most amazing astounding thing we can experience inside, and for the remainder of our lives on earth. The cross.... fully truth as well. A NEW knowledge is gifted to all, who truly & humbly seek to understand HIM, & the meaning behind HIS cross. It's something supranatural that takes place when we find & meet GOD- and really cannot be described...because it's something that comes to the 'seeker' outside of mankinds realm. It remains hidden until one chooses to find. It's one of HIS promises: J es us stated: "Seek & you WILL find". There is no 'maybe' that HE added into the words. And there is not a single thing in our human existence more important than HIS truth. This is why one of the greatest songs ever written, was written. Its title: Amazing Grace. .

  31. Game Breakers

    Multiverse concept is already present in Indian vedic literature which is written five thousands year, multiverse is reality not a comics idea because Vedas are never wrong.

  32. Nosreme Lavodnas

    i can make this video perpetual just click repeat...

  33. Brady Pearce

    Are there any other spectral instruments that we still haven't utilized in viewing black holes? I ask, because I have been fascinated by black holes since I was a kid, but just recently (at age 30) did I find out that scientists discovered the huge gamma rays spewing out of the ends of a black hole by pointing an "X-ray machine" towards the black holes. Just makes me wonder what we could possibly see using a "different spectral lens".

  34. Brady Pearce

    Are there any other spectral instruments that we still haven't utilized in viewing black holes? I ask, because I have been fascinated by black holes since I was a kid, but just recently (at age 30) did I find out that scientists discovered the huge gamma rays spewing out of the ends of a black hole by pointing an "X-ray machine" towards the black holes. Just makes me wonder what we could possibly see using a "different spectral lens".

  35. Brady Pearce

    Are there any other spectral instruments that we still haven't utilized in viewing black holes? I ask, because I have been fascinated by black holes since I was a kid, but just recently (at age 30) did I find out that scientists discovered the huge gamma rays spewing out of the ends of a black hole by pointing an "X-ray machine" towards the black holes. Just makes me wonder what we could possibly see using a "different lens".

  36. Sean Joseph

    Carnot cycle = Sterling engine...

  37. ASMR An Hour of WringWaltd!

    Hello Sir! Would it be logical to say, that under special conditions, that a spinning quasar can spin Faster than the Speed of Light, that this Speed would be the Speed of Dark, and that the faster the Speed of Dark that the Black Hole Spins, that it would become a “Flat Black.” Should this Speed Exist, whereas a Flat Black would be about 1 Photo in Width, I call it Speed of Epsilon, meaning Speed of an “Epic Oscillation.” Although Photons obey the Speed of Light, when Gravity overpowers a photon and takes it’s hold, they slow down and Darken, and would these “Darkened Photons” be considered to be true” Dark Matter or Dark Energy,” or maybe a Form of It? Also the temperature of this Flat Black would literally be so hot that because it’s on a 2 dimensional plane, and it’s Speed and Gravity is so High, it would cause Absolute Hot, if there is a thing, to also be Absolute Cold at the same, as gravity would at a certain point would cause this phenomenon. Do you think this is logical? I enjoy your show! Thank you very much. WringWaltd

    1. ASMR An Hour of WringWaltd!

      Also do you think there is a Direct Relation between a Photon’s Speed and it’s Brightness/Darkness. For instance, if gravity has a hold on a photon, slowing it to half it’s speed, therefore it seems it would only be half as bright, and the Point where it would Darken completely to Black, would be the point where it’s Speed is 100% negated.

  38. Dis Tortion

    Also, I guess it was high time for 4k. Some of the vids with many fancy graphics sort of were raped by youtube's vision of full hd.

  39. Dis Tortion

    At not screwing it all up... I've kind of always figured we're still ahead of our great filter, that is, something where we can't leave our petty differences aside, stop amassing imaginary wealth, prevent ourselves from destroying our planet (before we can escape it) and/or enslaving/murdering each other. If we really are unique, or at least progenitors of intelligence in the galaxy, we aren't really setting a good example. The depressing bit still remains - there isn't much suggesting that we're changing. At least quick enough. Collectively, we suck. We are horrible. We don't deserve the stars.

  40. KTPgaming PharaohCF

    I want to be a scientist but it is impossible 😓😓😓


    You don't talk about the ice after it moves opens the planet to heating. And like you said the earth holds heat which eventually leads to the core of the planet being hotter. The core of the planet being header eventually leads to crusty destabilization . What's the earth crust gets thin enough it will activate volcanoes and the smoke from said volcanoes will eventually black out the sky and start a new Ice Age vary quickly. Right???

  42. ProgRockDan2

    Featured on astral education

  43. Messerschmitt Mustang

    The conclusion: time travel is currently impossible

  44. L. Kärkkäinen

    Almost no greenhouse effect? That's funny, considering that the Martian atmosphere actually contains the same amount of CO2 as Earth's. The low total atmospheric pressure is because Mars lost its nitrogen, oxygen and water vapour into space.

  45. Clashing wi Nemesis.

    Just shoot the tortoise

  46. S. E.

    Stupidity of mankind will culminate in Quantum Facebook.

  47. Christobanistan


  48. bob733333

    Your lies are not an 'illusion'. Though you are 'ill'.


    why do i get the feeling that this video sounds like its dubbed..

  50. Michael Stewart

    Most likely they are not stupid enough to broadcast to everyone here I am. If a highly advancement species were to find humans they would likely treat us like we treat primivate civilization on our planet. They would likely wipe us out , enslave us and take our resources, or ignore us if we do not have anything they want or need. I think our scientists are foolish when they sent those disks with voyager. I can just imagine an alien race like the ones on Independence day getting hold of one of these disks and immediately head to Earth to conquer it. It would be ironic if the only reason a hostile civilization were to come to Earth is because of the fact that we needed to broadcast our position.

  51. Derek Hoiem

    There is no scientific proof for a multiverse.

  52. WadelDee

    What makes carbon-based life so special? What about virusses or silicon-based life or even other phenomena stabilize in other universes and, with time, develop into similarly complex organisms capable of these kinds of observation? Is our universe still this fine-tuned when taking them into account?

  53. E.L.Dorado

    In an ice age there are less plants and life which means less food and fuel so most of the life on the planet starves or freezes to death. In a warming greenhouse there is an abundance of plants and fuel and living organisms thrive and most of us have the ability to run an air conditioner. All this disastrous global warming talk is purely political propaganda.

    1. David Jaglin

      That is a very simplistic view. I think you miss out a few things. Heat stress on plants, extremes of weather, rising seas to name a few. Ecosystems cannot adapt to rapidly changing climactic conditions. Don't we depend on ecosystems?

  54. Jaap van der Velde

    Can we solve the CO2 crisis with renewables alone? Maybe. Can we afford to take that gamble? I don't think so - why bet on renewables alone if we can bet more safely on renewables paired with nuclear? We can get rid of nuclear over time, if renewables get as good as their proponents hope and if that doesn't happen, we'll be glad we got it in time. People will use the argument that having nuclear will just give people an out to continue wasting vast amounts of energy - but what I don't get is how people who don't trust others to do the right thing, do expect them to go along with a risky plan that will only work if everyone joins in.

  55. Joesph Dempsey

    I know the secrets of the universe and im not telling anyone.Ha ha fuck you all ha ha ha.

  56. StarLord Jae

    Would it hold true if a particle had negative energy

  57. Sean Joseph

    Had to end on scaremongering...Venus is hot because its atmosphere is much denser than Earth's.

    1. Sean Joseph

      @David Jaglin You're ignoring heat input from the sun. Gravity compression and the adiabatic cycle.

    2. David Jaglin

      @Sean Joseph First of all, it's collisions, not 'friction'. The collisions do not result in any loss or gain of energy. The average kinetic energy of gas particles is proportional to the absolute temperature of the gas. Before making disparaging comments, try to understand the basics. You just end up looking silly.

    3. Sean Joseph

      @David Jaglin You don't believe in friction then? Utterly astounding, flat earth club for you.

    4. David Jaglin

      @Sean Joseph 'Gas moving in weather cycles'? meaningless Energy input from the sun. yes. sure. And? Then CO2 forcing.

    5. Sean Joseph

      @David Jaglin Gas moving in weather cycles because of rotation and energy input from the sun is the main source of energy.

  58. Melinda Eshenour

    It would be nice if Tyson would allow other people to finish their sentence. He constantly stops people from speaking. It’s annoying.

  59. Dejay Rezme

    Haha if this isn't a cliffhanger. So how plausible is it actually that we just don't understand why the constants are how they are vs they are actually tuneable. Maybe they just have to be that way for some very plausible reason?

  60. John Bob

    Super useful!

  61. Nich Hodge

    And in one world he takes home Physics Girl after filming and has sex with her and in another he goes home alone

  62. Lunations AndEggos

    I know Planck’s constant by heart cuz I watched Stranger Things bunches of times. 6.62607004 :3

  63. daniel dorie

    to deep for me

  64. Bulent T

    what are you smoking man?

  65. rebel greninja

    yes it is possible but we need to be resourceful maybe we need a dyson sphere to make a dyson sphere

  66. god speed01

    My theory is that maybe other universes didn't go through the stone age

  67. Ryan McAlister

    I’ve got a theory that we don’t know sweet fuck all and scientists are not reliable sources of information that is factual coz they just say what ever the person paying their funding wants them to they are dirtier than a $2 crack whore

    1. Ryan McAlister

      David Jaglin hang on mate you have some scientific research that is for man made climate change funded by people who want that to be believed and then you have scientific research funded by the other side who says it’s complete and utter bullshit and than you also have independent scientists who also back the claim up that it’s a complete and utter joke on one side can actually be correct! So mate your big speech dosnt ring true in this corrupt world where scientists are bought and sold like whores and facts don’t mean fuck all when they are made up from completely bogus research and data that is bullshit. I don’t look silly at all I know very well how people are bought to say what the buyer wants

    2. David Jaglin

      A scientific theory is a whole body of work that includes evidence and demonstrable facts. e.g germ theory, gravitational theory, relativity.... You have no demonstrable facts or evidence. Most scientists get paid whatever the results. I strongly suggest you look into how research is funding before casting aspersions. You just end up looking silly. So how comes the scientists who were paid by the Koch brothers to disprove the hockey stick only found that it was real? See what I mean. A study funded by the oil industry ends up blaming fossil fuels for the rising temperatures.

  68. Reigh

    Matt this is what I know I valued my life but I just never produced value that keep me stabile and have faced this plus other traumas so long I now don't see the value in my life. See I can say a concept like "There are no Entangled Particles only Entangled Waveforms which form Emergence Patterns in a more granular scale then we can observe Waveforms" or to replace waveforms with strings "there are no entangles particles only entangled stings of the larger groups of entangles string structures three in one as they stack over each other in higher and higher dimensions that form leaderless patterns called Emergence Patterns" I simply use waveforms because groups of strings are still wave in nature literally both in properties and in natural phenomenon like emergence patterns. But as much as a jerk I was on your discord the other day my grandma just dies and I never produced enough value to stay off the streets and see her in a time when she was alive. I wanted to do more I was an RN and even when I couldn't find work made up the software which I can't complete but did fully develop to my happiness about the time she died. Just like that in the hospital I finally was able to really explore a linear algebra book. But while I can hypothesis I cannot develop a partial derivative to incorporate all of the patterns in physics defined as derivatives for a partial derivative optimization or machine partial derivative to them compare and train against more and more granular data like the rough edges of gravity and even in its tiniest of scales such as the gravity or a group of protons and then using that learn to predict the processes going on as thing enter a black hole and as hawking’s radiations leaves in a observed as granularly as we can measure for the predictions to see like an X-ray into an invisible body or define the emergence pattern more exactly of Entangled Waveforms or smaller Entangled Strings and how even large bodies and in the universe are entangles by similar constraints as to allow for life and what constraints are on infinite inflation to make multiverses possible with life and make predictions and how beginning logarithmically back to the beginning of infinite inflation is an allium shape with multiple bowls forming a sphere of a hot energy bush and how if you zoom out from that you find more of them like drops in the pond in 3d exploding out but in a balance rich poor some space some explosions and the constraints which allow that ebb and flow of birth and death of allium bush shaped multiverses you have emergence pattern constraints that make life just is that the very reason there is life is because of movement and the multiverses have it while the calm between these 3d spherical Allium bush waves has much less to non-canceled out like another interference pattern. But I can't do that math or even know those derivatives and I'm just in pain emotionally and physically trying to live what I have left. All I have for you though is a concept I don’t know the derivatives functions in Physics even or the data coming out just postulate on those concepts and drawings I do see and It’s taken me here in a divergent branch of thinking but lead me right back into string theory concepts from when I did that at Occupy while going to Seattle Central College and all my other years of science information in TV PBS others and on the net You Tube. I know it may sound hard to believe how much stress I'm under but not working but I can't explain it here and I'm going to call someone now that I finished this.

  69. tha Real Mike Zee

    I love this channel. I gotta get some PBS over-the-air bcuz I'm really into radio. I tell ya...I hated math; I failed miserably. I remember I had such a hard time multiplying & dividing, adding & subtracting FRACTIONS. Okay? So then one day I'm sitting in Music Theory 101. Sitting there writing out accurate rhythms correctly on stave paper. And, then it hit me: what was I doing? Adding, subtracting, multiplying, dividing fractions. Music is math too. It's just based more on intuitive feelings instead of concrete rational ideas. Altho it's governed by math like everything else. SO I wish I would've done better at the basic level bcuz as I started learning about quantum physics...I LOVE IT. Always have.

  70. Basic Dos Gaming

    Life is a computer simulation. The quntam eraser experiment pretty much proves this. The universe needs an observer to exist so it can't exist if you don't. In other words you created the universe

  71. jetthelooter

    The most likely explanation for any question is the most simple one that does not involve fairy godmothers. The answer is you have no clue, absolutely none as to how the universe works. All you have done is substitute one invisible undetectable unprovable god for another invisible undetectable unprovable god. Basically physicist who believe in dark matter believe in a flying spaghetti monster

  72. Scott T

    These days NOTHING gets "scienced".In todays cosmology,due to the belief in the ludicrous "THEORIES" by physics,the scientific approach or scientific method is NEVER and cant b used to test all this nonsense.Physics is in a crisis due to the amount of untestable,unprovable claims made by todays theoretical physicists.Its time to go back to our scientific roots where instead of inventing "stuff" like "dark matter" to keep a theory alive,we should discard the theory and come up with a new,testable,provable one,just as we used to do.

  73. Victor Castillo

    I really liked this video. You can’t imagine how hard has it been to explain people that life is highly improbable. There’s no reason for the universe to host life, it’s simply irrelevant. Yet, people discard this view automatically because for whatever reason they diminish the value of life and want to believe it’s very common everywhere, even if all evidence points towards the opposite. Great job on the video.


    Is he talking in English?

  75. Eric Pham

    The probability of quantum theory may be better understood if we take into account of time-space change make the differential repeatition of two locations in different time with same occurent because they are relative just like two Observer of a same events and reflected back to the event ocurent

  76. mekkel lowder

    Ok I doubt you will see this but from my understanding we try to use earthling attributes to search for alien life. things like dna, rna, earths features,oxygen, liquid water, all the byproducts life on Earth makes, ECT ... but we aren't looking for earthlings ... I feel like every planet in the universe has potential for some form of life ... And if it is habitable for even a few cells (or something else because it's not earth) than it has potential of evolution which could cause natural terraforming and eventually makeing the planet habitable for larger life forms that evolved around the changing of the planet said life terraformed (this sound a lot like earth ... But it's not ... Put this idea on literally any planet and it makes since for one reason... It's not earth based life) look on earth and there is actually evidence of this being possible ... Geothermal vents and volcanos hold life that makes little since to us ... But that's because we think all life needs the same things ...

  77. Scott T

    Hawking didnt confirm anything.NOTHING these days in theoretical physics can b proven.Its all unprovable nonsense and mathematics.Astronomy has been allowed to move so far from reality that its all untestable gibberish.

  78. Theninjagecko

    VP are nothing more than a mathematical trick. It gives us accurate predictions but we still cant answer what's really going on. Mathematics is getting us further and further away from the truth.

  79. David O'Connor

    My brain hurts sooo much right now. Please help me before it actually explodes. Please I beg you.

  80. Luka Kujundžić-Lujan

    music in background is amazing.. what is the source of that music?

  81. Guillaume Renou

    Well before thinking of how put more co2 on Mars, we should how think on how to réduce the one we are emitting on earth. On these terraforming technologies will not exist in far future nor the nearest one, because of the coming shortages on earth, and climate changes which will make our modern civilisation to collapse.

  82. BTC 3J8faXJCDKKS6AKvt7KNKhcEsfeKpEAShX

    nice script writing

  83. wakko151

    I thought reality had a curvature? didn't they discover evidence of that last year? I definitely could be wrong.

  84. aspektx

    If there is a president of the United States I hereby invite them to come visit me. I'll keep you all informed as to the results.

  85. kosmonaut dan

    Even if we could, it's a stupid idea. Space habitats are the way to go.

  86. Joan Enrique Torre Pinares

    Time travel is imposible, for the simple reason that time doesn't even exists. What we call time is actually movement, and in the theorical experiment of the planet of the apes one thing that is not in account is that earth will still be moving, and it's "future" is not located in the same place, but in the place where its movement will take the planet. So, no matter how "fast" you can travel, the movement of earth won't go faster. Come on guys, time is concept that abstracts movement and is useful for mathematical models and for applied physics, but you can't explain reality with a fiction.

  87. BTC 3J8faXJCDKKS6AKvt7KNKhcEsfeKpEAShX

    man we live in someone's simulation and they just upgraded to ryzen 3000≈∞

  88. Mr Marvellous

    We are alone and will soon go extinct.

  89. bipedalbob

    For me you don't explain this very well, but you have a lot of happy followers so I don't need to go into it, assuming you don't claim to be the author of this knowledge is there source that you got it from I could refer to? You've suggested most, even physics profs don't know it, I'd like to narrow my search.

  90. David B

    Just imagine if we had definitive proof that aliens existed. I truly believe it would unite the plant twords the common goal of making first contact and expanding our species through the galaxy. It would jumpstart so many technologies that no one is interested in! I just hate that I was born to early..

  91. DokktorDeth

    Preposterous video! Venus, my arse …

  92. makita

    The earth was seeded and humanity was helped.

  93. Dr.Satish Sharma

    Excellent..... thanks 🙏

  94. Enki

    CERN created a black hole and time "converged" on Dec 21, 2012. many incredible announcements coming soon.

  95. Jim Thomas

    Yes , time started after everything was created , but mankind was too stupid to start telling time until 2020 years ago

  96. Waffle Animations

    Man this isn’t world edit

  97. Nail Saggitarius

    Strings consist of strands of what? Energy? What is that?

  98. Chris Ernst

    His head looks CGI'd on his body. WTF is going on!

  99. Josh Bomar

    Please tell me you had a reason for your shirt being pulled to one side. It's throwing me off man. you arm and neck lines don't allow me to concentrate. I'm sorry

  100. Michael Noble

    He looks like human Shrek