Can you figure out the rule?
Did you see the exponents pattern? http://youtu.be/AVB8vRC6HIY
Why do you make people look stupid? http://bit.ly/12Fmlpl

How do you investigate hypotheses? Do you seek to confirm your theory - looking for white swans? Or do you try to find black swans? I was startled at how hard it was for people to investigate number sets that didn't follow their hypotheses, even when their method wasn't getting them anywhere.

In the video I say "when people came to Australia..." by which I meant, "when Europeans who believed all swans were white came to Australia..." I did not mean any offence to Indigenous Australians who were already in Australia at that time. Please accept my apologies for the poor phrasing if you were offended by it.

This video was inspired by The Black Swan by Nassim Taleb and filmed by my mum. Thanks mum!

Partly my motivation came from responses to my Facebook videos - social media marketers saying 'Facebook ads have worked for me so there can't be fake likes.' Just because you have only seen white swans, doesn't mean there are no black ones. And in fact marketers are only looking for white swans. They think it was invalid of me to make the fake Virtual Cat page: 'well of course if it's a low quality page you're going to get low quality likes.' But my point is this is black swan bait, something they would never make because their theory is confident in the exclusive existence of white swans.

I am working on some big new projects I'm excited to share with you!

So this video is a little different from most of the others. The channel is an element of truth, after all, not an element of science. This is my truth. It may not be everyone's but that's ok too.

Clips included were from:
Chernobyl and Pripyat - drone shots from shooting Uranium
Obsidian dome, California
Panum Crater
El Capitan
The Pyramids of Giza
Toronto buildings
The Holocaust Memorial in Berlin
Abu Simbel temple at Aswan, Egypt
Sydney Harbour
Milky way time-lapse from the badlands of South Australia
Sunset over Warrnambool, Victoria
Big Bang animation courtesy of NASA
Sunrise over Bondi
Water off New Caledonia
Great white sharks in the Neptune Islands, South Australia
Crosswalk at Town Hall Sydney
EDUtubers at the YouTube EDU summit in San Francisco
Concert in Sydney
Jetpacking in Western Sydney
Vi's triangles at Perimeter Institute, Waterloo Canada
Aurora Borealis north of Fairbanks Alaska
Sagrada Familia, Barcelona, Spain
Hiking with MinutePhysics in Washington State

Music Licensed from cuesongs.com "The Secret Tower" by Nicholas O

Does quantum entanglement make faster-than-light communication possible?
What is NOT random? http://bit.ly/NOTrandoVe
First, I know this video is not easy to understand. Thank you for taking the time to attempt to understand it. I've been working on this for over six months over which time my understanding has improved. Quantum entanglement and spooky action at a distance are still debated by professors of quantum physics (I know because I discussed this topic with two of them).

Does hidden information (called hidden variables by physicists) exist? If it does, the experiment violating Bell inequalities indicates that hidden variables must update faster than light - they would be considered 'non-local'. On the other hand if you don't consider the spins before you make the measurement then you could simply say hidden variables don't exist and whenever you measure spins in the same direction you always get opposite results, which makes sense since angular momentum must be conserved in the universe.

Everyone agrees that quantum entanglement does not allow information to be transmitted faster that light. There is no action either detector operator could take to signal the other one - regardless of the choice of measurement direction, the measured spins are random with 50/50 probability of up/down.

Special thanks to:
Prof. Stephen Bartlett, University of Sydney: http://bit.ly/1xSosoJ
Prof. John Preskill, Caltech: http://bit.ly/1y8mJut

Looking Glass Universe: http://bit.ly/17zZH7l
Physics Girl: http://bit.ly/PhysGirl
MinutePhysics: http://bit.ly/MinPhys
Community Channel: http://bit.ly/CommChannel
Nigel, Helen, Luke, and Simon for comments on earlier drafts of this video.

Filmed in part by Scott Lewis: http://google.com/+scottlewis

Music by Amarante "One Last Time": http://bit.ly/VeAmarante

How much would it take for you to risk $10?
Check out Audible: http://bit.ly/AudibleVe
Can you solve this? http://bit.ly/248Ve
Regression to the mean: http://bit.ly/VeRTTM

Help translate Veritasium videos into other languages: http://veritasium.subtitl.us

Psychological literature shows that we are more sensitive to small losses and than small gains, with most people valuing a loss around 1.5-2.5 times as much as a gain. This means that we often turn down reasonable opportunities for fear of the loss. However over the course of our lives we will be exposed to many risks and opportunities and this invariably means that taking every small reasonable bet will leave us better off than saying no to all of them.

NOTE: The video is not saying to accept every bet, only those with reasonable odds (preferably in your favour), and those which if you lose would not cause significant financial or other damage. In those cases it is wise to be loss averse!

Filmed by Adrian Tan

Thanks to Physics Girl for suggestions on previous versions of this video. https://www.youtube.com/physicswoman

We have just seen the first image of a black hole, the supermassive black hole in the galaxy M87 with a mass 6.5 billion times that of our sun. But what is that image really showing us?

This is an awesome paper on the topic by J.P. Luminet:
Image of a spherical black hole with thin accretion disk
Astronomy and Astrophysics, vol. 75, no. 1-2, May 1979, p. 228-235
https://ve42.co/luminet

Using my every day intuition I wondered: will we see the "shadow" of the black hole even if we're looking edge on at the accretion disk? The answer is yes because the black hole warps space-time, so even if we wouldn't normally be able to see the back of the accretion disk, we can in this case because its light is bent up and over the black hole. Similarly we can see light from the bottom of the back of the accretion disk because it's bent under the bottom of the black hole. Plus there are additional images from light that does a half turn around the black hole leading to the inner rings.

What about the black hole "shadow" itself? Well initially I thought it can't be an image of the event horizon because it's so much bigger (2.6 times bigger). But if you trace back the rays, you find that for every point in the shadow, there is a corresponding ray that traces back to the event horizon. So in fact from our one observing location, we see all sides of the event horizon simultaneously! In fact infinitely many of these images, accounting for the virtually infinite number of times a photon can orbit the black hole before falling in. The edge of the shadow is due to the photon sphere - the radius at which light goes around in closed orbits. If a light ray coming in at an oblique angle just skims the photon sphere and then travels on to our telescopes, that is the closest 'impact parameter' possible, and it occurs at sqrt(27)/2*r_s

Huge thanks to:
Prof. Geraint Lewis
University of Sydney https://ve42.co/gfl
Like him, I'm hoping (predicting?) we'll see some moving images of black holes tomorrow

Prof. Rana Adhikari
Caltech https://ve42.co/Rana

Riccardo Antonelli - for excellent images of black holes, simulations and ray-tracing code, check out:
https://ve42.co/rantonels

The Event Horizon Telescope Collaboration
Check out their resources and get your local link for the livestream here: https://ve42.co/EHT

Special thanks to Patreon supporters:
Donal Botkin, Michael Krugman, Ron Neal, Stan Presolski, Terrance Shepherd, Penward Rhyme

Filming by Raquel Nuno
Animation by Maria Raykova

This tiny robot can jump higher than anything else in the world. This video is sponsored by Brilliant. The first 200 people to sign up via https://brilliant.org/veritasium get 20% off a yearly subscription.

Huge thanks to Dr. Elliot Hawkes and the rest of the group - Charles Xiao, Chris Keeley, Dr. Morgan Pope, and Dr. Günter Niemeyer - for having us at UCSB and showing us their high-flying jumper. This work was partially supported by an Early Career Faculty Grant from NASA’s Space Technology Research Grants Program.

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References:

Hawkes, E.W., Xiao, C., Peloquin, R., Keeley, C., Begley, M.R., Pope, M.T., & Niemeyer, G. (2022). Engineered jumpers overcome biological limits via work multiplication. Nature, 604, 657-661. – https://rdcu.be/cMePc
https://ve42.co/Hawkes2022
Fernandez, S. (2022). Hitting New Heights. The Current, UC Santa Barbara. – https://ve42.co/Fernandez2022
Bushwick, S. (2022). Record-Breaking Jumping Robot Can Leap a 10-Story Building. Engineering, Scientific American. – https://ve42.co/Bushwick2022
Mack, E. (2022). This Robot Can Leap Nine Stories in One Jump, Will Go Even Higher on Moon. Science, CNET. – https://ve42.co/Mack2022
Ashby, M. (2020). Materials Selection in Mechanical Design (4th edition). Elsevier.
Jumping robot leaps to record heights. Nature Video - https://ve42.co/NatureJumper
MultiMo-Bat Robot - https://ve42.co/MultiMoBat
Galago Jump - https://ve42.co/GalagoJump
Slingshot Spider - https://ve42.co/SlingshotSpider

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Special thanks to Patreon supporters: RayJ Johnson, Brian Busbee, Jerome Barakos M.D., Amadeo Bee, TTST, Balkrishna Heroor, Chris LaClair, John H. Austin, Jr., OnlineBookClub.org, Matthew Gonzalez, Eric Sexton, john kiehl, Nathan Lanza, Diffbot, Gnare, Dave Kircher, Burt Humburg, Blake Byers, Dumky, Evgeny Skvortsov, Meekay, Bill Linder, Paul Peijzel, Josh Hibschman, Mac Malkawi, Michael Schneider, jim buckmaster, Juan Benet, Robert Blum, Sunil Nagaraj, Richard Sundvall, Lee Redden, Stephen Wilcox, Marinus Kuivenhoven, Michael Krugman, Cy 'kkm' K'Nelson, Sam Lutfi, Ron Neal

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Written by Emily Zhang and Derek Muller
Filmed by Derek Muller and Trenton Oliver
Animation by Mike Radjabov and Ivy Tello
Edited by Trenton Oliver
Additional video/photos supplied by Pond5 and Getty Images
Music from Epidemic Sound
Produced by Derek Muller, Petr Lebedev, and Emily Zhang

A head-vaporizing laser with a perfect wavelength detecting sub-proton space-time ripples.
Huge thanks to Prof Rana Adhikari and LIGO: http://ligo.org
Here's how he felt when he learned about the first ever detection: https://youtu.be/ViMnGgn87dg

Thanks to Patreon supporters:
Nathan Hansen, Donal Botkin, Tony Fadell, Saeed Alghamdi, Zach Mueller, Ron Neal
Support Veritasium on Patreon: http://bit.ly/VePatreon

A lot of videos have covered the general overview of the discovery of gravitational waves, what they are, the history of the search, when they were found but I wanted to delve into the absurd science that made the detection possible.

When scientists want one megawatt of laser power, it's not just for fun (though I'm sure it's that too), it's because the fluctuations in the number of photons is proportional to their square root, making more powerful beams less noisy (as a fraction of their total). The smoothest mirrors were created not for aesthetic joy but because when you're trying to measure wiggles that are a fraction the width of a proton, a rough mirror surface simply won't do.

Filmed by Daniel Joseph Files

Music by Kevin MacLeod, http://www.incompetech.com "Black Vortex" (appropriately named)

Music licensed from Epidemic Sound http://epidemicsound.com "Observations 2" (also appropriately named)

As the universe expands, #expanding #space is said to "stretch" photons. But if it stretches photons, does it also stretch molecules, galaxies and you? A portion of this video was sponsored by Salesforce. Go to https://salesforce.com/veritasium to learn more.

Special thanks to Geraint Lewis - this video was based on his paper "On the relativity of redshifts"
https://arxiv.org/abs/1605.08634
Check out his YouTube channel: https://ve42.co/gfl and books: https://ve42.co/GFLbooks

References:
Expanding Space: the Root of all Evil?
Matthew J. Francis, Luke A. Barnes, J. Berian James, Geraint F. Lewis
https://arxiv.org/abs/0707.0380

Editing and VFX by Trenton Oliver
Thumbnail by Ignat Berbeci

Music from https://epidemicsound.com

#SMB #smallbiz #startups #SalesforceEssentials

Celsius never devised nor used the scale that now bears his name.

Veritasium is now on Patreon: http://patreon.com/veritasium

Special thanks to Michael Stevens of Vsauce! http://youtube.com/vsauce1

More info about Celsius and temperature scales: http://wke.lt/w/s/2I6Nu

References for this video:

A History of the Thermometer and its uses in Meteorology by W. E. Knowles Middleton

Absolute Zero and the Conquest of Cold by Tom Shachtman

The Science of Measurement, A Historical Survey by Herbert Arthur Klein

Lehrbuch der Chemie by Jöns Jakob Berzelius

Special Thanks to the Uppsala University Museum
I filmed this in Uppsala in the summer of 2012! So I've been thinking about this idea for a very long time. I'm glad to finally have it out there in the world.

Kodak detected the first atomic bomb before anyone else figured it out. Then they made a deal not to tell anyone. Thanks to HBO Max, and their new show raised by Wolves for sponsoring this video! https://rb.gy/alghwn

Thanks to Uranium: Twisting the Dragon's Tail for the opening clip: https://www.pbs.org/show/urani....um-twisting-dragons-

References:
Albuquerque Tribune Bulletin, July 16, 1945 – https://www.marshallfoundation.....org/library/documen

Webb, J. H. (1949). The fogging of photographic film by radioactive contaminants in cardboard packaging materials. Physical Review, 76(3), 375.

Julian Webb at Oak Ridge – Snavely, B. B. (1989). Julian H. Webb. PhT, 42(7), 87.https://physicstoday.scitation.....org/doi/pdf/10.1063

Radium in watch dials – https://www.epa.gov/radtown/radioactivity-antiques

A 1958 video about how Kodak film is made, noting the careful monitoring of radioactive contaminants – https://www.youtube.com/watch?v=9qjBJOFImaU&t=597s&ab_channel=OwenMorgan

Radioactive fallout in 1951 - https://www.nytimes.com/1951/0....2/03/archives/increa

1998 senate hearing – https://www.govinfo.gov/conten....t/pkg/CHRG-105shrg44

Institute of Medicine and National Research Council. 1999. Exposure of the American People to Iodine-131 from Nevada Nuclear-Bomb Tests: Review of the National Cancer Institute Report and Public Health Implications. Washington, DC: The National Academies Press. https://doi.org/10.17226/6283. https://www.cancer.gov/about-c....ancer/causes-prevent

Baby Teeth Survey – Reiss, L. Z. (1961). Strontium-90 absorption by deciduous teeth. Science, 134(3491), 1669-1673.

Strontium 90 and Cancer rates – Gould, J. M., Sternglass, E. J., Sherman, J. D., Brown, J., McDonnell, W., & Mangano, J. J. (2000). Strontium-90 in deciduous teeth as a factor in early childhood cancer. International Journal of Health Services, 30(3), 515-539.

Wine forensics – Hubert, P., Perrot, F., Gaye, J., Médina, B., & Pravikoff, M. S. (2009). Radioactivity measurements applied to the dating and authentication of old wines. Comptes Rendus Physique, 10(7), 622–629. doi:10.1016/j.crhy.2009.08.007

Strontium 90 in forensics – Maclaughlin-Black, S. M., Herd, R. J., Willson, K., Myers, M., & West, I. E. (1992). Strontium-90 as an indicator of time since death: a pilot investigation. Forensic science international, 57(1), 51-56.

Research and Writing by Derek Muller, Petr Lebedev, and Jonny Hyman

Filmed and edited by Derek Muller
Animations by Ivy Tello and Jonny Hyman
Music by Jonny Hyman
Additional Music from:
Epidemic Sound https://epidemicsound.com "Seaweed"
Kevin MacLeod https://incompetech.com "Lightless dawn"
Craig Conrad https://www.craigconard.com/royaltyfree "ASTRAL"

This video is sponsored by Brilliant. The first 200 people to sign up via https://brilliant.org/veritasium get 20% off a yearly subscription. Astronomers think there should be 5 times as much dark matter as ordinary matter – a shadow universe that makes up most of the mass in the universe. But after decades of trying, no experiments have found any trace of dark matter – except one.

A massive thanks to the wonderful people at the ARC Centre of Excellence for Dark Matter Physics https://www.centredarkmatter.org for showing us around and being on camera – Fleur Morrison, A/Prof Phillip Urquijo, Prof Elisabetta Barberio, Madeleine Zurowski and Grace Lawrence.
Thanks to Leo Fincher-Johnson and everyone at the Stawell gold mine for having us.
Massive thanks to Prof. Geraint Lewis – Geraint has been Veritasium’s go-to expert for anything astrophysics and cosmology related. Please check out his website, and buy his books, they’re great – https://www.geraintflewis.com
Thanks to Prof. Timothy Tait for the help to make sure we got the science right.
Thanks to Ingo Berg for illustrating the effect of dark matter on the rotation of a galaxy https://beltoforion.de/en/spir....al_galaxy_renderer/s

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Galaxy cluster simulation from IllustrisTNG – https://www.tng-project.org
Venn Diagram of Dark Matter from Tim Tait – https://ve42.co/venn
The Bullet Cluster Image from Magellan, Hubble and Chandra telescopes – https://ve42.co/BC2
Bullet cluster animation from Andrew Robertson / Institute for Computational Cosmology / Durham University – https://ve42.co/BC3

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Bernabei, R., Belli, P., Cappella, F., Cerulli, R., Dai, C. J., d’Angelo, A., ... & Ye, Z. P. (2008). First results from DAMA/LIBRA and the combined results with DAMA/NaI. The European Physical Journal C, 56(3), 333-355. – https://ve42.co/DAMA2008

Zwicky, F. (1933). Die rotverschiebung von extragalaktischen nebeln. Helvetica physica acta, 6, 110-127. – https://ve42.co/Zwicky1

Zwicky, F. (1937). On the Masses of Nebulae and of Clusters of Nebulae. The Astrophysical Journal, 86, 217. – https://ve42.co/Zwicky2

Rubin, V. C., & Ford Jr, W. K. (1970). Rotation of the Andromeda nebula from a spectroscopic survey of emission regions. The Astrophysical Journal, 159, 379. – https://ve42.co/Rubin1

Bosma, A., & Van der Kruit, P. C. (1979). The local mass-to-light ratio in spiral galaxies. Astronomy and Astrophysics, 79, 281-286. – https://ve42.co/Bosma1

Milgrom, M. (1983). A modification of the Newtonian dynamics as a possible alternative to the hidden mass hypothesis. The Astrophysical Journal, 270, 365-370. – https://ve42.co/mond1

Sanders, R. H., & McGaugh, S. S. (2002). Modified Newtonian dynamics as an alternative to dark matter. Annual Review of Astronomy and Astrophysics, 40(1), 263-317. – https://ve42.co/Mond2

M. Markevitch; A. H. Gonzalez; D. Clowe; A. Vikhlinin; L. David; W. Forman; C. Jones; S. Murray & W. Tucker (2004). "Direct constraints on the dark matter self-interaction cross-section from the merging galaxy cluster 1E0657-56". Astrophys. J. 606 (2): 819–824. – https://ve42.co/BC1

Great website about the CMB – http://background.uchicago.edu..../~whu/intermediate/d

Galli, S., Iocco, F., Bertone, G., & Melchiorri, A. (2009). CMB constraints on dark matter models with large annihilation cross section. Physical Review D, 80(2), 023505. – https://ve42.co/CMB1

Antonello, M., Barberio, E., Baroncelli, T., Benziger, J., Bignell, L. J., Bolognino, I., ... & Xu, J. (2019). The SABRE project and the SABRE Proof-of-Principle. The European Physical Journal C, 79(4), 1-8. – https://ve42.co/SABRE1


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Special thanks to Patreon supporters: Inconcision, Kelly Snook, TTST, Ross McCawley, Balkrishna Heroor, Chris LaClair, Avi Yashchin, John H. Austin, Jr., OnlineBookClub.org, Dmitry Kuzmichev, Matthew Gonzalez, Eric Sexton, john kiehl, Anton Ragin, Diffbot, Micah Mangione, MJP, Gnare, Dave Kircher, Burt Humburg, Blake Byers, Dumky, Evgeny Skvortsov, Meekay, Bill Linder, Paul Peijzel, Josh Hibschman, Mac Malkawi, Michael Schneider, jim buckmaster, Juan Benet, Ruslan Khroma, Robert Blum, Richard Sundvall, Lee Redden, Vincent, Stephen Wilcox, Marinus Kuivenhoven, Clayton Greenwell, Michael Krugman, Cy 'kkm' K'Nelson, Sam Lutfi, Ron Neal

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Written by Derek Muller and Petr Lebedev
Edited by Trenton Oliver
Animation by Ivy Tello and Mike Radjabov
Filmed by Derek Muller and Petr Lebedev
Additional video/photos supplied by Getty Image
B-roll supplied by Stawell Gold Mine
Music from Epidemic Sound
Thumbnail by Ignat Berbeci
Produced by Derek Muller, Petr Lebedev, and Emily Zhang

High-energy rechargeable batteries seemed impossible, until we made them. Sponsored by CodeRabbit. Cut code review time and bugs in half. Try CodeRabbit at https://coderabbit.link/veritasium

If you’re looking for a molecular modelling kit, try Snatoms, a kit I invented where the atoms snap together magnetically - https://ve42.co/SnatomsV

▀▀▀
0:00 What’s inside a battery?
4:11 How does a battery work?
7:15 How did we increase battery power?
11:13 The first rechargeable lithium battery
13:29 The Tiny Needles That Kill Batteries
16:06 Goodenough? We can do better
20:07 The birth of the lithium-ion battery
27:10 Why do batteries explode?
29:31 Blowing up a battery

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A massive thank you to Dr Billy Wu, Dr Sam Cooper, Dr Derek Sui, Professor Magda Titirici, Dr Jingyu Feng, Dr Monica Marinescu, Li Ren Thow, Genlin Liu and Sam Riley; and to Professor Guillermo Rein, Dr Harry Mitchell, Hanna Berry, and Dr Nick Kalogeropoulos at Imperial College London for their invaluable contributions to this video. And a big thank you to Conrad Duncan for all his help in pulling everything together.

We’re incredibly grateful to Kurt Kelty and the team at General Motors for their time and expertise.

Thanks also go to Dr Yuzhang Li and Prof Jay Morton Turner for all their help on the project.

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References: https://ve42.co/RefsBatteries

Image References: https://ve42.co/ImgRefsBatt

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Special thanks to our Patreon supporters:

Adam Foreman, Albert Wenger, Alex Porter, Alexander Tamas, Anton Ragin, armedtoe, Balkrishna Heroor, Bertrand Serlet, Blake Byers, Bruce, Dave Kircher, David Johnston, David Tseng, Evgeny Skvortsov, Garrett Mueller, Gnare, gpoly, Ibby Hadeed, JT, Jeromy Johnson, Jon Jamison, Juan Benet, Keith England, KeyWestr, Kyi, Lee Redden, Marinus Kuivenhoven, Matthias Wrobel, Meekay, meg noah, Michael Bush, Michael Krugman, Orlando Bassotto, Paul Peijzel, Richard Sundvall, Robert Oliveira, Sam Lutfi, Tj Steyn, Ubiquity Ventures, Walter Flinn, wolfee

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Writers: Emilia Gyles, Casper Mebius, Gregor Čavlović & Derek Muller
Producer & Director: Emilia Gyles
Editor: Trenton Oliver
Camera Operators: Tas Underwood, Emilia Gyles, Gregor Čavlović & Derek Muller
Animators: Andrew Neet, Emma Wright, Fabio Albertelli, Mike Radjabov & Rokas Viksraitis
Illustrators: Jakub Misiek, Maria Gusakovich, Isaac McRee, Nataly Zhuk & Kaitlyn Chille
Assistant Editor: James Stuart
Researchers: HyoJeong Choi, Aakash Singh Bagga & Gabe Strong
Thumbnail Designers: Ren Hurley, Ben Powell & Abdallah Rabah
Production Team: Rob Beasley Spence & Josh Pitt
Executive Producers: Derek Muller & Casper Mebius
Additional video/photos supplied by Getty Images, Pond5
Music from Epidemic Sound

The sun has been producing light for about five billion years but where does all its energy come from? The most common idea is that the sun is burning gas - like a giant fireball in the sky. If this were true, the sun would have gone out long ago. So how is the sun actually fuelling itself? It is converting its own mass into energy. By combining protons (the nucleus of hydrogen) into helium, it squeezes some mass into energy - 4.3 billion kg per second. It is Einstein's famous E=mc^2 which gives us the quantitative relationship between mass and energy, where c is the speed of light.

Earth has been closer to Nuclear War more times than you’d think. Head over to
https://hensonshaving.com/veritasium and enter code 'Veritasium' for 100 free blades with the purchase of a razor. Make sure to add both the razor and the blades to your cart for the code to take effect.

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References:
List of Broken Arrows -- https://ve42.co/AtomicArchive https://ve42.co/BrokenArrowsReport
Declassified Goldsboro Report -- https://ve42.co/Goldsboro
Operation ChromeDome -- https://ve42.co/OperationChromeDome
CIA website -- https://ve42.co/CIA

Cataclysmic cargo: The hunt for four missing nuclear bombs after a B-52 crash -- https://ve42.co/WoPo
THE LAST FLIGHT OF HOBO 28 -- https://ve42.co/lastflight
The Voice of Larry Messinger is from this documentary -- https://ve42.co/Messinger
Even Without Detonation, 4 Hydrogen Bombs From ’66 Scar Spanish Village -- https://ve42.co/NYTPalomares
Decades Later, Sickness Among Airmen After a Hydrogen Bomb Accident -- https://ve42.co/NYTPalomares2
Picture of ReVelle -- https://ve42.co/JackReVelle1
Great NPR where the audio of ReVelle is from -- https://ve42.co/JackReVelle2
CIA Website -- https://ve42.co/CIA


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Special thanks to our Patreon supporters:
Anton Ragin, Balkrishna Heroor, Bernard McGee, Bill Linder, Burt Humburg, Dave Kircher, Diffbot, Evgeny Skvortsov, Gnare, Jesse Brandsoy, John H. Austin, Jr., john kiehl, Josh Hibschman, Juan Benet, KeyWestr, Lee Redden, Marinus Kuivenhoven, Mario Bottion, MaxPal, Meekay, meg noah, Michael Krugman, Orlando Bassotto, Paul Peijzel, Richard Sundvall, Sam Lutfi, Stephen Wilcox, Tj Steyn, TTST, Ubiquity Ventures

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Directed by Petr Lebedev
Written by Petr Lebedev and Derek Muller
Edited by Peter Nelson
Animated by Fabio Albertelli, Jakub Misiek, Ivy Tello and Mike Radjabov
Filmed by Derek Muller
Produced by Petr Lebedev, Han Evans, and Derek Muller
Additional video/photos supplied by Getty Images and Pond5
Music from Epidemic Sound

People have witnessed supernovae for millennia, but what threat do they pose to life on Earth? This video is sponsored by Brilliant. You can get started for free, or the first 200 people to sign up via https://brilliant.org/veritasium get 20% off a yearly subscription.

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A massive thanks to Prof. Hans-Thomas Janka for helping us with the physics of supernovae and GRBs. A massive thanks to Prof. Brian Thomas for all of his help with the terrestrial effects of supernovae and GRBs. This video would not have been possible without them. Also thanks to Dr. Luke Barnes for his initial help with the literature search.

Hydrogen bomb vs Supernova fact was taken from this great article by xkcd/Randall Munroe – https://what-if.xkcd.com/73/ (based on the calculation by Andrew Karam, 2002)

Cosmic bubble footage from
https://www.cfa.harvard.edu/ne....ws/1000-light-year-w

Neutrino driven SN explosion simulations from https://iopscience.iop.org/art....icle/10.1088/2041-82

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References:

Melott, A. et al. (2019). Hypothesis: Muon radiation dose and marine megafaunal extinction at the End-Pliocene supernova. Astrobiology, 19(6), 825-830. – https://ve42.co/Melott1

Thomas, B. C. et al. (2016). Terrestrial effects of nearby supernovae in the early Pleistocene. The Astrophysical Journal Letters, 826(1), L3 – https://ve42.co/Thomas1

Melott, A. L., & Thomas, B. C. (2019). From cosmic explosions to terrestrial fires?. The Journal of Geology, 127(4), 475-481. – https://ve42.co/Melott2

Fields, B. et al. (2019). Near-Earth supernova explosions: Evidence, implications, and opportunities. arXiv preprint arXiv:1903.04589. – https://ve42.co/Fields1

Thomas, B. C., Atri, D., & Melott, A. L. (2021). Gamma-ray bursts: not so much deadlier than we thought. Monthly Notices of the Royal Astronomical Society, 500(2), 1970-1973. – https://ve42.co/Thomas2

Melott, A. et al. (2004). Did a gamma-ray burst initiate the late Ordovician mass extinction?. International Journal of Astrobiology, 3(1), 55-61. – https://ve42.co/Melott3

Firestone, R. B. (2014). Observation of 23 supernovae that exploded less than 300 pc from Earth during the past 300 kyr. The Astrophysical Journal, 789(1), 29. – https://ve42.co/firestone1

Janka, H. T. (2017). Neutrino emission from supernovae. arXiv preprint arXiv:1702.08713. – https://ve42.co/Janka1

Janka, H. T., & Hillebrandt, W. (1989). Neutrino emission from type II supernovae-an analysis of the spectra. Astronomy and astrophysics, 224, 49-56. – https://ve42.co/Janka2

Janka, H. T. (2017). Neutrino-driven explosions. arXiv preprint arXiv:1702.08825. – https://ve42.co/Janka3

Karam, P. A. (2002). Gamma and neutrino radiation dose from gamma ray bursts and nearby supernovae. Health physics, 82(4), 491-499. – https://ve42.co/Karam1

Melott, A. L., Thomas, et al.. (2017). A supernova at 50 pc: effects on the Earth's atmosphere and biota. The Astrophysical Journal, 840(2), 105. – https://ve42.co/Melott4

Ludwig, P., et al. (2016). Time-resolved 2-million-year-old supernova activity discovered in Earth’s microfossil record. Proceedings of the National Academy of Sciences, 113(33), 9232-9237. – https://ve42.co/Ludwig1

Gritschneder, et al. (2011). The supernova triggered formation and enrichment of our solar system. The Astrophysical Journal, 745(1), 22. – https://ve42.co/Gritschneder1

Motizuki, Y., Takahashi, et al. (2009). An Antarctic ice core recording both supernovae and solar cycles. arXiv preprint arXiv:0902.3446. – https://ve42.co/Motizuki

Zucker, C. et al. (2022). Star formation near the Sun is driven by expansion of the Local Bubble. Nature, 601(7893), 334-337. – https://ve42.co/Zucker1

Hirata, K. et al.(1987). Observation of a neutrino burst from the supernova SN1987A. – https://ve42.co/Hirata1

Hayes, L. A., & Gallagher, P. T. (2022). A Significant Sudden Ionospheric Disturbance Associated with Gamma-Ray Burst GRB 221009A. Research Notes of the AAS, 6(10), 222.

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Written by Petr Lebedev & Derek Muller
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Animation by Fabio Albertelli, Jakub Misiek, Alex Drakoulis, Ivy Tello, Mike Radjabov, and Charlie Davies
Filmed by Derek Muller
Additional Research by Kovi Rose & Katie Barnshaw
Video/photos supplied by NASA, ESA, Pond5, and Getty Images
Music from Epidemic Sound & Jonny Hyman
Produced by Derek Muller, Petr Lebedev, and Emily Zhang

My entry to the techNyou Science Ambassadors competition, visit www.facebook.com/talkingtechnology and www.youtube.com/technyouvids to find out more about these guys.

The General Theory of Relativity tells us gravity is not a force, gravitational fields don't exist. Objects tend to move on straight paths through curved spacetime. Thanks to Caséta by Lutron for sponsoring this video. Find out more at: https://www.lutron.com/veritasium

Huge thanks to Prof. Geraint Lewis for hours of consulting on this video so I could get these ideas straight in my own brain. Check out his YouTube channel: https://ve42.co/gfl or his books: https://ve42.co/GFLbooks

Amazing VFX, compositing, and editing by Jonny Hyman
2D animations by Ivy Tello
Filmed by Steven Warren and Raquel Nuno
Special thanks to Petr Lebedev for reviews and script consultation
Music by Jonny Hyman and from Epidemic Sound https://epidemicsound.com

Rocket made by Goodnight and Co.
Screen images in rocket by Geoff Barrett

Slow motion rocket exhaust footage from Joe Barnard at BPS.Space
https://www.youtube.com/channe....l/UCILl8ozWuxnFYXIe2

The rainiest place on earth isn’t where you might expect. Get exclusive NordVPN deal here ➵ https://NordVPN.com/veritasium. It’s risk free with Nord’s 30 day money-back guarantee!

Special thanks to our Patreon supporters! Join this list to help us keep our videos free, forever:
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If you’re looking for a molecular modeling kit, try Snatoms – a kit I invented where the atoms snap together magnetically – https://ve42.co/SnatomsV

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Huge thanks to Okouchi-San and Dr. Sakai and everyone at NIED and the Large Scale Rainfall Simulator for their time, expertise and access to this amazing facility.

A big thank you to Prof. Olga Mavrouli and Prof. Bill Schulz for their invaluable expertise on the mechanisms of landslides.

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References:
Ulbrich, C. W. (1983). Natural variations in the analytical form of the raindrop size distribution. Journal of climate and applied meteorology, 1764-1775. – https://ve42.co/Ulbrich83

Van Boxel, J. H. (1997, November). Numerical model for the fall speed of rain drops in a rain fall simulator. In Workshop on wind and water erosion (Vol. 5, pp. 77-85). – https://ve42.co/Boxel87

Canuti, P., Focardi, P., & Garzonio, C. (1985). Correlation between rainfall and landslides. Bulletin of Engineering Geology & the Environment, 32(1).

Tsaparas, I., Rahardjo, H., Toll, D. G., & Leong, E. C. (2002). Controlling parameters for rainfall-induced landslides. Computers and geotechnics, 29(1), 1-27. – https://ve42.co/Tsaparas2002

Nakamura, H., & Oosawa, M. (2021, March). Effects of the underground discharge channel/reservoir for small urban rivers in the Tokyo area. In IOP Conference Series: Earth and Environmental Science (Vol. 703, No. 1, p. 012029). IOP Publishing. – https://ve42.co/Nakamura21

Guthrie, R. H., & Evans, S. G. (2004). Magnitude and frequency of landslides triggered by a storm event, Loughborough Inlet, British Columbia. Natural Hazards and Earth System Sciences, 4(3), 475-483. – https://ve42.co/Guthrie2004

Images & Video:
Miyako, Iwate Tsunami via ANNnewsCH - https://ve42.co/Miyako2011
Mount Onake Volcano via BBC News - https://ve42.co/BBCOnake
Typhoon Jebi via Al Jazeera - https://ve42.co/TyphoonJebi
East Asia Typhoons via CBC News - https://ve42.co/TyphoonCBC
Atami Landslide via The Quint - https://ve42.co/Atami2021
Atami Landslide via news.com.au - https://ve42.co/2ndAtami2021
Sendai Earthquake via ANNnewsCH - https://ve42.co/SendaiQuake
Nagasaki Mudslide via The Telegrap - https://ve42.co/NagasakiMudslide
Wajima Landslide via Guardian News - https://ve42.co/WajimaLandslide
Drone Rainfall Test via AIZAWAchan - https://ve42.co/DroneRain
Car Rainfall Test via TIER IV - https://ve42.co/CarRainTest
Rainfall Simulator via NIED - https://ve42.co/RainfallSim1
External Footage of Simulator via NIED - https://ve42.co/RainfallSim2
Landslide Simulations via NIED - https://ve42.co/RainfallSim3
Typhoon Prapiroon via Force Thirteen - https://ve42.co/TyphoonPrapiroon
Yanohigashi Floods via CNA - https://ve42.co/YanohigashiFloods
Japan Floods via The Telegraph - https://ve42.co/TelegraphFlood
Japan Floods via euronew - https://ve42.co/EuroNewsFlood
Typhoon Hagibis via Guardian News - https://ve42.co/TyphoonHagibis
Typhoon Hagibis via SCMP - https://ve42.co/TyphoonHagibisSCMP
Satellite Imagery of Hagibis via Force Thirteen - https://ve42.co/HagibisSatellite
Tokyo Flood Control System via NikkeiAsia.com - https://ve42.co/FloodControl
Landslides Footage via Underworld - https://ve42.co/MonsterLandslides
Norway Landslide via ABC7 - https://ve42.co/NorwayLandslide
Planet Destruction via BBC - https://ve42.co/BBCDestruction
B.C. Climate Change Danger via CBC News - https://ve42.co/BCClimateChange
Canada’s Logging Roads via CBC News - https://ve42.co/CBCLogging

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Directed by Petr Lebedev
Written by Petr Lebedev
Edited by Peter Nelson
Additional Research by Gregor Čavlović
Animated by Fabio Albertelli
Illustrations by Jakub Misiek
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Produced by Petr Lebedev, Han Evans and Gregor Čavlović
Thumbnail by Peter Sheppard
Additional video/photos supplied by Getty Images
Music from Epidemic Sound

Adhesives based on gecko skin can hold huge weights – without sticking to anything. Head to https://brilliant.org/Veritasium to start your free trial. The first 200 of you will get 20% off Brilliant’s annual premium subscription.

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Thanks to Dr. Mark Cutkosky, Tony Chen, Amar Hajj-Ahmad, and the rest of the Biomimetics and Dexterous Manipulation Lab at Stanford University for showing us the power of gecko adhesives.

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References:
Russell, A. P., Stark, A. Y., & Higham, T. E. (2019). The integrative biology of gecko adhesion: historical review, current understanding, and grand challenges. Integrative and comparative biology, 59(1), 101-116. – https://ve42.co/Russell2019

Hajj-Ahmad, A., Suresh, S. A., and Cutkosky, M. R. (June 6, 2021). "Cutting to the Point: Directly Machined Metal Molds for Directional Gecko-Inspired Adhesives." ASME. J. Micro Nano-Manuf. – https://ve42.co/Hajj-Ahmad2021

Kerst, Capella F., "Gecko inspired adhesives : permanent practical manufacturing, new materials, and applications," PhD Thesis, Stanford University, December 2020. – https://ve42.co/Kerst2020

Suresh, S.A. "Engineering Gecko-Inspired Adhesives." Ph.D. thesis, Stanford University, 2020. [Online]. – https://ve42.co/Suresh2020

Suresh, S.A., Kerst, C.F., Cutkosky, M.R., Hawkes, E.W. "Spatially variant microstructured adhesive with one-way friction." Journal of the Royal Society Interface. 2019. – https://ve42.co/Suresh2019

Glick, P., Suresh, S.A., Ruffatto III, D., Cutkosky, M.R., Tolley, M.T., and Parness, A. "A soft robotic gripper with gecko-inspired adhesive." Robotics and Automation Letters. 2018. – https://ve42.co/Glick2018

Christensen, D.L., Hawkes, E.W., Suresh, S.A., Ladenheim, K. and Cutkosky, M.R., "µTugs: Enabling Microrobots to Deliver Macro Forces with Controllable Adhesives," IEEE/ICRA 2015 (preprint). – https://ve42.co/Christensen2015

Hawkes, E. W., "Applying Dry Adhesives to the Real World," Ph.D. thesis, Stanford University, 2015. – https://ve42.co/Hawkes2015

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Written by Derek Muller & Petr Lebedev
Edited by Trenton Oliver
Animation by Ivy Tello
Filmed by Derek Muller & Albert Leung
Additional video/photos supplied by Pond5 & Getty Images
Music from Epidemic Sound
Exec. Produced by Derek Muller, Petr Lebedev, and Emily Zhang

Do you really know how big the universe is? There’s a data driven way to read the news: go to https://ground.news/veritasium to get 30% off the Vantage plan and see through sensationalized reporting.

If you’re looking for a molecular modeling kit, try Snatoms – a kit I invented where the atoms snap together magnetically – https://ve42.co/SnatomsV


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A huge thank you to Dr. Ashmeet Singh for his expert feedback on this video.


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References:
Fun video by RealLifeLore about the scale of the Universe - https://www.youtube.com/watch?v=Iy7NzjCmUf0&pp=ygUkcmVhbCBsaWZlIGxvcmUgc2NhbGUgb2YgdGhlIHVuaXZlcnNl
Moon Facts via NASA - https://ve42.co/NASAMoon
Titan Facts via NASA - https://ve42.co/Titan
Mercury Facts via NASA - https://ve42.co/Mercury
Why Pluto is no Longer a Planet, BBC News via YouTube - https://www.youtube.com/watch?v=iIk29MnzZWA&pp=ygUYcGx1dG8gbm8gbG9uZ2VyIGEgcGxhbmV0
Pluto, Wikipedia - https://ve42.co/WikiPluto
Eris, Wikipedia - https://ve42.co/WikiEris
Brown, M. E., & Schaller, E. L. (2007). The mass of dwarf planet Eris. Science, 316(5831), 1585-1585. - https://ve42.co/Brown2007
Trans-Neptunian object, Wikipedia - https://ve42.co/WikiTNO
IAU 2006 General Assembly Press Release, via IAU - https://ve42.co/IAU2006
Solar System Moons via NASA - https://ve42.co/NASAMoons
Solar System Asteroids via NASA - https://ve42.co/Asteroids
Solar System, Wikipedia - https://ve42.co/WikiSolarSystem
How many stars are in the Universe via ESA - https://ve42.co/ESAStars
Catalog of Exoplanets via exoplanet - https://ve42.co/ExoplanetCatalog
Crowther, T. W., Glick, H. B., Covey, K. R., Bettigole, C., Maynard, D. S., Thomas, S. M., ... & Bradford, M. A. (2015). Mapping tree density at a global scale. Nature, 525(7568), 201-205. - https://ve42.co/Crowther2015
Galaxy, Wikipedia - https://ve42.co/WikiGalaxy
Counting Galaxies with the Hubble Space Telescope via NASA - https://ve42.co/CountingGalaxies
Conselice, C. J., Wilkinson, A., Duncan, K., & Mortlock, A. (2016). The evolution of galaxy number density at z8 and its implications. The Astrophysical Journal, 830(2), 83. - https://ve42.co/Conselice2016
Sagan, C., & Druyan, A. (2011). Pale blue dot: A vision of the human future in space. Ballantine books.

Images & Video:
Clip of Titan’s Surface, NASA via YouTube - https://www.youtube.com/watch?v=xn3-0a19sC8
Clips of Pluto Had it Coming, The Late Show with Stephen Colbert via YouTube - https://www.youtube.com/watch?v=5nqT7XrYRPc
Image of Solar System Objects - https://ve42.co/SolarSystemObjects


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Special thanks to our Patreon supporters:
Adam Foreman, Anton Ragin, Balkrishna Heroor, Bill Linder, Blake Byers, Burt Humburg, Chris Harper, Dave Kircher, David Johnston, Diffbot, Evgeny Skvortsov, Gnare, John H. Austin, Jr., john kiehl, Josh Hibschman, Juan Benet, KeyWestr, Lee Redden, Marinus Kuivenhoven, Max Paladino, Meekay, meg noah, Michael Krugman, Paul Peijzel, Richard Sundvall, Sam Lutfi, Stephen Wilcox, Tj Steyn, TTST, Ubiquity Ventures


▀▀▀
Directed by Casper Mebius
Written by Casper Mebius and Derek Muller
Additional research & fact checking by Gregor Čavlović
Edited by Peter Nelson
Animated by Ivy Tello and Alondra Vitae
Filmed by Derek Muller, Raquel Nuno and Zyan Treadwell
Produced by Derek Muller, Casper Mebius and Han Evans

Additional video/photos supplied by Getty Images, StoryBlocks and by courtesy of NASA, NASA's Goddard Space Flight Center/SDO, NASA JPL, NASA/JPL-Caltech NASA GSFC, NASA HQ, NASA's Scientific Visualization Studio, NCSA, A. Kritsuk, M. Norman

Music from Epidemic Sound
Thumbnail by Peter Sheppard