GRAVITY

We're not done with gravity yet - General Relativity hasn't had the final say. Go to http://brilliant.org/DrBecky and sign up for free. The first 200 people that go to that link will get 20% off the annual premium subscription. 00:00 - Video Introduction 01:00 - A brief history of gravity 01:59 - Einstein's theory of General Relativity 06:21 - Problems in Cosmology and why we care 08:46 - How do we come up with new theories of gravity? 09:23 - Starting with an observation e.g. MOND 12:20 - Adding an extra field/force 14:12 - Adding extra dimensions e.g. string theory 16:25 - Conclusions 19:09 - Bloopers Thanks to Dr Oliver Tattersal, an expert on modified gravity theories for helping me with the content of this video: https://www2.physics.ox.ac.uk/contacts/people/tattersall Here are the review papers that he sent my way to get me started for those who want a deep dive (note: written for the academic community - you may prefer to read Pedro Ferreira's book 'The Perfect Theory' which is written for a public audience: https://www.amazon.co.uk/dp/B00CTMAAN4/ref=dp-kindle-redirect?_encoding=UTF8&btkr=1) Ferreira (2019) - https://arxiv.org/pdf/1902.10503.pdf Berti et al. (2015) - https://arxiv.org/pdf/1501.07274.pdf Clifton et al. (2012) - https://arxiv.org/pdf/1106.2476.pdf And BONUS - a fairly recent review on String Theory from Mukhi (2011) - https://arxiv.org/pdf/1110.2569.pdf -- The artwork in the background is a scientifically accurate map showing the orbits of more than 18000 asteroids in the Solar System, created by Eleanor Lutz. Find out more and buy one here: https://eleanorlutz.com/mapping-18000-asteroids ---- 📚 "Space: 10 Things You Should Know": http://bit.ly/SpaceDrBecky 📚 US & Canada version: "Space at the speed of light" (same book, different title): https://www.penguinrandomhouse.com/books/635406/space-at-the-speed-of-light-by-dr-becky-smethurst/ 📚 German translation "Das kleine Buch vom großen Knall" : https://www.dtv.de/buch/becky-smethurst-das-kleine-buch-vom-grossen-knall-28254/ --- 🔔 Don't forget to subscribe and click the little bell icon to be notified when I post a new video! --- 🔭 Royal Astronomical Society podcast that I’m co-hosting 😱 🥳- podfollow.com/supermassive --- 📹 Dr. Becky also presents videos on Sixty Symbols: https://www.youtube.com/user/sixtysymbolsand Deep Sky Videos: https://www.youtube.com/user/DeepSkyVideos --- 👩🏽‍💻 Dr Becky Smethurst is an astrophysicist researching galaxies and supermassive black holes at Christ Church at the University of Oxford. http://drbecky.uk.com https://rebeccasmethurst.co.uk

It’s been 120 years since Henry Cavendish measured the gravitational constant with a pair of lead balls suspended by a wire. The fundamental nature of gravity still eludes our best minds - but those secrets may be revealed by turning back to the Cavendish experiment. That steampunk contraption may even reveal the existence of extra dimensions of space. Sign Up on Patreon to get access to the Space Time Discord! https://www.patreon.com/pbsspacetime Check out the Space Time Merch Store https://pbsspacetime.com/ Sign up for the mailing list to get episode notifications and hear special announcements! https://mailchi.mp/1a6eb8f2717d/spacetime Hosted by Matt O'Dowd Written by Katie McCormick & Matt O'Dowd Graphics by Leonardo Scholzer, Yago Ballarini, & Pedro Osinski Directed by: Andrew Kornhaber Camera Operator: Bahaar Gholipour Executive Producers: Eric Brown & Andrew Kornhaber #space #astrophysics #gravity Special Thanks to Our Patreon Supporters Big Bang Supporters Alexander Tamas David Nicklas Fabrice Eap Juan Benet Morgan Hough Radu Negulescu Quasar Supporters Christina Oegren Mark Heising Vinnie Falco Hypernova Supporters William Bryan Chuck Zegar Danton Spivey Donal Botkin Edmund Fokschaner Hank S John Hofmann John Pollock John R. Slavik Jordan Young Joseph Salomone Julian Tyacke Mathew Matthew O'Connor Syed Ansar Timothy McCulloch Gamma Ray Burst Supporters A G Adrian Hatch AlecZero Andreas Nautsch Andrew Richmond Bradley Jenkins Brandon labonte Brandon Lattin Brian Blanchard Cass Costello Craig Stonaha Dan Warren Daniel Lyons David Bethala David Hughes DFaulk Eric Kiebler Frederic Simon Geoffrey Short Graydon Goss Greg Smith Jennifer Crosley John Funai John Griffith John Robinson Josh Thomas Justin Waters Kevin Lee Kevin Warne Kyle Hofer Malte Ubl Mark Daniel Cohen Michael Conroy Mirik Gogri Nick Virtue Nick Wright Nickolas Andrew Freeman Patrick Sutton Paul Rose Protius Protius Robert Ilardi Scott Gossett Sean Warniaha Shane Calimlim Simon Oliphant Steve Bradshaw Tatiana Vorovchenko Tim Stephani Tonyface Tybie Fitzhugh Yannick Weyns Yurii Konovaliuk

Full podcast episodes: http://www.askaspaceman.com Support: http://www.patreon.com/pmsutter Follow: http://www.twitter.com/PaulMattSutter and http://www.facebook.com/PaulMattSutter What was Newton’s genius? Why was his work so controversial? Why are his laws of motion so radical? I discuss these questions and more in today’s Ask a Spaceman! Follow all the show updates at http://www.askaspaceman.com, and help support the show at http://www.patreon.com/pmsutter! Keep those questions about space, science, astronomy, astrophysics, and cosmology coming to #AskASpaceman for COMPLETE KNOWLEDGE OF TIME AND SPACE! Music by Jason Grady and Nick Bain.

You can buy Universe Sandbox 2 here: http://amzn.to/2yJqwU6 Or get a shirt: https://teespring.com/stores/whatdamath Hello and welcome! My name is Anton and in this video, we will talk about newly discovered gravitational waves that came from the direction of Betelgeuse star and some other new discoveries about the unusual star. Detection report: https://gracedb.ligo.org/superevents/S200114f/view/ Support this channel on Patreon to help me make this a full time job: https://www.patreon.com/whatdamath Space Engine is available for free here: http://spaceengine.org Enjoy and please subscribe. Twitter: https://twitter.com/WhatDaMath Facebook: https://www.facebook.com/whatdamath Twitch: http://www.twitch.tv/whatdamath Bitcoins to spare? Donate them here to help this channel grow! 1GFiTKxWyEjAjZv4vsNtWTUmL53HgXBuvu The hardware used to record these videos: CPU: https://amzn.to/2LZFQCJ Video Card: https://amzn.to/2M1W26C Motherboard: https://amzn.to/2JYGiQQ RAM: https://amzn.to/2Mwy2t4 PSU: https://amzn.to/2LZcrIH Case: https://amzn.to/2MwJZz4 Microphone: https://amzn.to/2t5jTv0 Mixer: https://amzn.to/2JOL0oF Recording and Editing: https://amzn.to/2LX6uvU Thank you to all Patreon supporters of this channel Specifically, great thanks to the following members: Morrison Waud Vlad Manshin Mark Teranishi TheHuntress Ralph Spataro Albert B. Cannon Lilith Dawn Greg Lambros adam lee Gabriel Seiffert Henry Spadoni J Carter Jer Silver surfer Konrad Kummli Nick Dolgy UnexpectedBooks.com Mario Rahmani George Williams Shinne Jakub Glos Johann Goergen Jake Salo LS Greger Lyndon Riley Lauren Smith Michael Tiganila Russell Sears Vinod sethi Dave Blair Robert Wyssbrod Randal Masutani Michael Mitsuda Assaf Dar Sagol Liam Moss Timothy Welter MD Barnard Rabenold Gordon Cooper Tracy Burgess Douglas Burns Jayjay Volz Anataine Deva Kai Raphahn Sander Stols Bodo Graßmann Daniel Charles Smith Daniel G. Eugene Sandulenko gary steelman Max McNally Michael Koebel Sergio Ruelas Steven Aiello Victor Julian Castillo xyndicate Honey Suzanne Lyons Olegas Budnik Dale Andrew Darling Niji Peter Hamrak Matthew Lazear Alexander Afanasyev Anton Newman Anton Reed

Full podcast episodes: http://www.askaspaceman.com Support: http://www.patreon.com/pmsutter Follow: http://www.twitter.com/PaulMattSutter and http://www.facebook.com/PaulMattSutter How did String Theory get started? What has made the idea so popular over the decades? Can we ever truly have a theory of quantum gravity? What is supersymmetry, the landscape, and the AdS/CFT Correspondence? What do holograms have to do with this? How many dimensions do we live in? Why does String Theory have such a hard time making predictions? How are we supposed to judge a theory that isn’t done yet? It’s a non-stop String Theory bonanza as I discuss these questions and more in today’s Ask a Spaceman! Follow all the show updates at http://www.askaspaceman.com, and help support the show at http://www.patreon.com/pmsutter! Keep those questions about space, science, astronomy, astrophysics, and cosmology coming to #AskASpaceman for COMPLETE KNOWLEDGE OF TIME AND SPACE! Music by Jason Grady and Nick Bain.

You can buy Universe Sandbox 2 here: http://amzn.to/2yJqwU6 Or get a shirt: https://teespring.com/stores/whatdamath Hello and welcome! My name is Anton and in this video, we will talk about a discovery of a new planet called Mascara-4b that was discovered using a new method known as Gravity Darkening. Paper: https://arxiv.org/pdf/1911.05025.pdf Support this channel on Patreon to help me make this a full time job: https://www.patreon.com/whatdamath Space Engine is available for free here: http://spaceengine.org Enjoy and please subscribe. Twitter: https://twitter.com/WhatDaMath Facebook: https://www.facebook.com/whatdamath Twitch: http://www.twitch.tv/whatdamath Bitcoins to spare? Donate them here to help this channel grow! 1GFiTKxWyEjAjZv4vsNtWTUmL53HgXBuvu The hardware used to record these videos: CPU: https://amzn.to/2LZFQCJ Video Card: https://amzn.to/2M1W26C Motherboard: https://amzn.to/2JYGiQQ RAM: https://amzn.to/2Mwy2t4 PSU: https://amzn.to/2LZcrIH Case: https://amzn.to/2MwJZz4 Microphone: https://amzn.to/2t5jTv0 Mixer: https://amzn.to/2JOL0oF Recording and Editing: https://amzn.to/2LX6uvU Thank you to all Patreon supporters of this channel Specifically, great thanks to the following members: Morrison Waud Vlad Manshin Mark Teranishi TheHuntress Daniel Rosvall Ralph Spataro Lilith Dawn Albert B. Cannon Greg Lambros adam lee Jer Henry Spadoni Nick Dolgy Konrad Kummli UnexpectedBooks.com J Carter Gabriel Seiffert Shinne George Williams Jakub Glos Johann Goergen Lyndon Riley LS Greger Jake Salo Michael Tiganila Lauren Smith Olegas Budnik Dave Blair Sander Stols Kai Raphahn Sergio Ruelas Arikkat Unnikrishnan Steven Becky Tracy Burgess Gordon Cooper Steve Wotton Jayjay Volz Anataine Deva Honey Suzanne Lyons Daniel Coleman Matthew Lazear xyndicate Steven Aiello

Full podcast episodes: http://www.askaspaceman.com Support: http://www.patreon.com/pmsutter Follow: http://www.twitter.com/PaulMattSutter and http://www.facebook.com/PaulMattSutter How did String Theory get started? What has made the idea so popular over the decades? Can we ever truly have a theory of quantum gravity? What is supersymmetry, the landscape, and the AdS/CFT Correspondence? What do holograms have to do with this? How many dimensions do we live in? Why does String Theory have such a hard time making predictions? How are we supposed to judge a theory that isn’t done yet? It’s a non-stop String Theory bonanza as I discuss these questions and more in today’s Ask a Spaceman! Follow all the show updates at http://www.askaspaceman.com, and help support the show at http://www.patreon.com/pmsutter! Keep those questions about space, science, astronomy, astrophysics, and cosmology coming to #AskASpaceman for COMPLETE KNOWLEDGE OF TIME AND SPACE! Music by Jason Grady and Nick Bain.

Sign Up on Patreon to get access to the Space Time Discord! https://www.patreon.com/pbsspacetime Check out the Space Time Merch Store https://pbsspacetime.com/ It’s time we talked about loop quantum gravity. What exactly is it? What are the loops? And can it really defeat string theory in our quest for a Theory of Everything? Hosted by Matt O'Dowd Written by Graeme Gossel & Matt O'Dowd Graphics by Leonardo Scholzer Directed by: Andrew Kornhaber Executive Producers: Eric Brown & Andrew Kornhaber The holy grail of physics is to connect our understanding of the tiny scales of atoms and subatomic particles with that of the vast scales of planets, galaxies, and the entire universe. To connect quantum physics with Einstein’s general theory of relativity. Our search for a theory of quantum gravity is a century old, and we’ve talked quite a bit about it already, including what’s probably the lead contender - string theory. But string theory isn’t the only game in town - or so some physicists believe. There may be another way to reconcile the physics of the tiny and the gigantic - another way to a theory of quantum gravity that avoids a lot of conceptual baggage like tiny wiggling strings made of coiled up extra dimensions. That other way would be loop quantum gravity, and today we’re going to learn exactly what it is. Special Thanks to Our Patreon Supporters Big Bang Supporters: David Barnholdt David Boyer David Nicklas Fabrice Eap Juan Benet matt miller Morgan Hough Quasar: Mark Heising Mark Rosenthal Vinnie Falco Hypernova: chuck zegar Danton Spivey Donal Botkin Edmund Fokschaner Hank S joe pearce John Hofmann John R. Slavik Jordan Young Joseph Salomone Mathew Matthew O'Connor Syed Ansar Gamma Ray Burst: A G Adrien Molyneux AlecZero Andreas Nautsch Bradley Jenkins Brandon labonte Brian Dan Warren Daniel Lyons David Bethala DFaulk Frederic Simon Geoffrey Short Graydon Goss Greg Smith James Flowers John Funai John Griffith John Michael Kerr John Pollock John Robinson Jonathan Nesfeder Joseph Dillman Josh Thomas Kevin Lee Kevin Warne Kyle Hofer Malte Ubl Nick Virtue Nick Wright Paul Rose Scott Gossett Sean Warniaha Tim Stephani Tonyface Yurii Konovaliuk

AstroInformatics 2019 Conference: AstroInformatics for Large Projects http://astroinformatics2019.org/

AstroInformatics 2019 Conference: AstroInformatics for Large Projects http://astroinformatics2019.org/

The Universe started in the Big Bang and ever since then space has been expanding - increasing the distance between galaxies ever since. Galaxy mergers are also very common though - so how does this happen if galaxies are always moving apart from each other? #bigquestions My book ' Space: 10 Things You Should Know' is out NOW worldwide (except for US & Canada - more info soon) you can find it in your local bookshop or order it here: http://bit.ly/SpaceDrBecky ----------- Follow me on Twitter: https://twitter.com/drbecky_ And on Instagram: https://www.instagram.com/drbecky_s/ Don't forget to subscribe and click the little bell icon to be notified when I post a new video! --------- Dr Becky Smethurst is an astrophysicist researching galaxies and supermassive black holes at Christ Church at the University of Oxford. http://drbecky.uk.com

One hundred years ago this month, observations performed during a total solar eclipse proved for the first time the gravitational bending of light predicted by Albert Einstein’s new theory of gravity, general relativity. In this video, Günther Hasinger, ESA Director of Science, reflects on this historic measurement that inaugurated a century of exciting experiments, investigating gravity on Earth and in space and proving general relativity in ever greater detail. On Earth, we deal with gravity every day. We feel it, we fight it, and – more importantly – we investigate it. Space agencies such as we routinely launch spacecraft against our planet’s gravity, and sometimes these spacecraft borrow the gravity of Earth or other planets to reach interesting places in the Solar System. We study the gravity field of Earth from orbit, and fly experiments on parabolic flights, sounding rockets and the International Space Station to examine a variety of systems under different gravitational conditions. On the grandest scales, our space science missions explore how gravity affects planets, stars and galaxies across the cosmos and probe how matter behaves in the strong gravitational field created by some of the Universe’s most extreme objects like black holes. Copyright: ESA Credits: ESA/CESAR (solar eclipse sequence); ESO/M. Kornmesser (black hole); Royal Astronomical Society (negative photo of the 1919 solar eclipse); ESA/Hubble, NASA (gravitationally lensed quasar); ESO/Gravity Consortium/L. Calçada (black hole simulation) ★ Subscribe: http://bit.ly/ESAsubscribe and click twice on the bell button to receive our notifications. Check out our full video catalog: http://bit.ly/SpaceInVideos Follow us on Twitter: http://bit.ly/ESAonTwitter On Facebook: http://bit.ly/ESAonFacebook On Instagram: http://bit.ly/ESAonInstagram On Flickr: http://bit.ly/ESAonFlickr We are Europe's gateway to space. Our mission is to shape the development of Europe's space capability and ensure that investment in space continues to deliver benefits to the citizens of Europe and the world. Check out http://www.esa.int/ESA to get up to speed on everything space related. Copyright information about our videos is available here: http://www.esa.int/spaceinvideos/Terms_and_Conditions #ESA #SpaceScience #Gravity

Do string theory and loop quantum gravity consider retro-causality or quantum entanglement? Did the universe start with the Big Bang? Jim Baggott answers audience questions following his talk. Subscribe for regular science videos: http://bit.ly/RiSubscRibe Watch the talk: https://youtu.be/dW7J49UTns8 Jim Baggott is an award-winning science writer. He trained as a scientist, completing a doctorate in chemical physics at the University of Oxford in the early 80s, before embarking on post-doctoral research studies at Oxford and at Stanford University in California. This Q&A was filmed at the Ri on 12 February 2019. --- A very special thank you to our Patreon supporters who help make these videos happen, especially: Darren Jones, Dave Ostler, David Lindo, Elizabeth Greasley, Greg Nagel, Ivan Korolev, Lester Su, Osian Gwyn Williams, Radu Tizu, Rebecca Pan, Robert Hillier, Roger Baker, Sergei Solovev and Will Knott. --- The Ri is on Patreon: https://www.patreon.com/TheRoyalInstitution and Twitter: http://twitter.com/ri_science and Facebook: http://www.facebook.com/royalinstitution and Tumblr: http://ri-science.tumblr.com/ Our editorial policy: http://www.rigb.org/home/editorial-policy Subscribe for the latest science videos: http://bit.ly/RiNewsletter

In this week's QA, I answer if Opportunity could ever phone home, are there stars between galaxies, and who, exactly, is Chad? Featuring a special guest answer from Dr. Becky. Check out Dr. Becky's channel at: https://www.youtube.com/channel/UCYNbYGl89UUowy8oXkipC-Q 01:45 What if Opportunity phoned home? 03:11 Stars between galaxies? 04:39 Who is Chad? 05:28 Why can't we calculate the size of the Universe? 08:28 Least toxic comment section 09:15 Where does the Solar System rotation come from? 11:00 Did Panspermia happen multiple times? 12:55 Could a black hole form from molecule collisions? 15:24 What would it take to repair Opportunity? 17:26 Why can't we accelerate for 1G? Reference: https://www.quora.com/What-is-the-maximum-speed-a-chemical-rocket-can-achieve 19:28 Is Oumuamua a Von Neumann probe? 21:18 Is there anything that doesn't orbit anything? Our Book is out! https://www.amazon.com/Universe-Today-Ultimate-Viewing-Cosmos/dp/1624145442/ Audio Podcast version: ITunes: https://itunes.apple.com/us/podcast/universe-today-guide-to-space-audio/id794058155?mt=2 RSS: https://www.universetoday.com/audio What Fraser's Watching Playlist: https://www.youtube.com/playlist?list=PLbJ42wpShvmkjd428BcHcCEVWOjv7cJ1G Weekly email newsletter: https://www.universetoday.com/newsletter Weekly Space Hangout: https://www.youtube.com/channel/UC0-KklSGlCiJDwOPdR2EUcg/ Astronomy Cast: https://www.youtube.com/channel/UCUHI67dh9jEO2rvK--MdCSg Support us at: http://www.patreon.com/universetoday More stories at: http://www.universetoday.com/ Twitch: https://twitch.tv/fcain Follow us on Twitter: @universetoday Like us on Facebook: https://www.facebook.com/universetoday Google+ - https://plus.google.com/+universetoday/ Instagram - http://instagram.com/universetoday Team: Fraser Cain - @fcain / [email protected] Karla Thompson - @karlaii / https://www.youtube.com/channel/UCEItkORQYd4Wf0TpgYI_1fw Chad Weber - [email protected]

The science of expansion: Andromeda, gravity, and the ‘Big Rip’ New videos DAILY: https://bigth.ink Join Big Think Edge for exclusive video lessons from top thinkers and doers: https://bigth.ink/Edge ---------------------------------------------------------------------------------- The Andromeda Galaxy and our Milky Way are on a collision course that will obliterate life on Earth 4.5 billion years from now.The universe is expanding in all directions, all at once – so why are Andromeda and the Milky Way drawing nearer? The gravity between them is a stronger force than expansion.The rate of expansion is accelerating. If it continues to speed up, its force may become strong enough pull things apart that are currently held together by superior forces: Our galaxy, the solar system, and even the atoms in our bodies. That possible ending to the universe is known as the 'Big Rip'. ---------------------------------------------------------------------------------- MICHELLE THALLER Dr. Michelle Thaller is an astronomer who studies binary stars and the life cycles of stars. She is Assistant Director of Science Communication at NASA. She went to college at Harvard University, completed a post-doctoral research fellowship at the California Institute of Technology (Caltech) in Pasadena, Calif. then started working for the Jet Propulsion Laboratory's (JPL) Spitzer Space Telescope. After a hugely successful mission, she moved on to NASA's Goddard Space Flight Center (GSFC), in the Washington D.C. area. In her off-hours often puts on about 30lbs of Elizabethan garb and performs intricate Renaissance dances. For more information, visit NASA. ---------------------------------------------------------------------------------- TRANSCRIPT: MICHELLE THALLER: One of the questions I get asked most commonly as an astronomer is if almost all the galaxies in the universe are flying away from us in space, why is the Andromeda Galaxy getting closer to us? Does that somehow mean that the Big Bang works differently in different parts of the universe? And the answer simply is: no. Space is expanding because of the Big Bang. All of space is expanding in every direction all at once and from our viewpoint that means that it looks like all the other galaxies are moving away from us. But not all the universe around us appears to be expanding. For example, the Earth doesn't seem to be getting any farther away from the Sun. The Sun is not getting any farther away from our galaxy. Thank about smaller scales, like your body; your body (luckily) is not expanding along with the universe. And the reason is that the expansion of the universe is actually a pretty gentle force; you really only notice it out in the middle of nowhere in the vast reaches of space between the galaxies. There's a lot of space out of there, so there is a lot of space to expand and so you really notice this expansion. But there are things that are stronger than the expansion force. For example, my body is held together by chemical forces and by electrical forces. That is much, much stronger than the tiny little push that space has to expand inside me. I hold together very well. One of the analogies I think about is: You could try to push over the Empire State Building by blowing on it. You are actually exerting a force on the Empire State Building by blowing on it, you can measure that force, but you're not going to blow over the Empire State Building. There are things that are much stronger than this omnipresent but gentle force of the expansion of the universe. The gravity between the Sun and the Earth is stronger than space's pressure to expand over that scale. The force of gravity is stronger than the outward push of the expansion of the universe. That's also true of the galaxy, we are held in orbit around the center of the galaxy. Gravitationally, that's much stronger than any expansion force. So why is Andromeda different? Andromeda is close enough to our Milky Way Galaxy that the gravity between the two is strong enough for the two to start moving together. Yeah, space is expanding between us and the Andromeda Galaxy, but gravity is accelerating Andromeda toward us faster than that expansion. And, in fact, that means that Andromeda is going to collide with the Milky Way in a couple billion years. And we see this happening all over the universe. There are clusters of galaxies where the galaxies are close enough together that they are merging and colliding. When galaxies are far enough away from each other that the gravitational force is weaker, the acceleration due to gravity is weaker than the outward expansion, then they start moving away. Now one of the intriguing things is that we don't know what the future holds when it comes to the expansion force of the universe. Just recently in the last couple of decades we've measured... For the full transcript, check out https://bigthink.com/videos/the-science-of-expansion-andromeda-gravity-and-the-big-rip

A discussion of Messier 70 to kick off a description of Gravothermal Catastrophe. More links and info in full description ↓↓↓ Watch our videos on all the Messier Objects: http://bit.ly/MessierObjects Sorry for the Catastrophic typo! Featuring Professor Mike Merrifield from the University of Nottingham. https://twitter.com/astromikemerri Discuss this video on Brady's subreddit: https://redd.it/amo9ny Deep Sky Videos website: http://www.deepskyvideos.com/ Twitter: https://twitter.com/DeepSkyVideos Facebook: http://www.facebook.com/DeepSkyVideos More about the astronomers in our videos: http://www.deepskyvideos.com/pages/contributors.html Supported by the University of Nottingham Back us on Patreon: https://www.patreon.com/deepskyvideos Video by James Hennessy and Brady Haran

In this week's Questions Show, I wonder if there's a way ion engines can give us artificial gravity, if electromagnetic rail guns can launch space craft, and should we be worried about returning alien pathogens back to Earth? 00:22 Ion drive artificial acceleration 02:17 CMB absolute speed 04:55 Magnetic launch system 08:19 What if aliens don't use the same EM spectrum 10:13 Pathogens from Europa? 11:43 Universal time system? 12:51 Secret fusion projects 15:02 What if we find life on Europa? 18:17 What is the Milky Way orbiting? 19:26 How do we dispose of heat in space? 21:18 Higher orbit, slower speed? 23:24 How to judge the speed of galaxies? Featuring a special guest answer from Athena Brensberger at Astroathens. Check out her channel here: https://www.youtube.com/channel/UCdhES1DtY9klIfJsjGKs3gQ Our Book is out! https://www.amazon.com/Universe-Today-Ultimate-Viewing-Cosmos/dp/1624145442/ Audio Podcast version: ITunes: https://itunes.apple.com/us/podcast/universe-today-guide-to-space-audio/id794058155?mt=2 RSS: https://www.universetoday.com/audio Video Podcast version: ITunes: https://itunes.apple.com/bh/podcast/universe-today-video/id794057165?mt=2 RSS: https://www.universetoday.com/video What Fraser's Watching Playlist: https://www.youtube.com/playlist?list=PLbJ42wpShvmkjd428BcHcCEVWOjv7cJ1G Weekly email newsletter: https://www.universetoday.com/newsletter Support us at: http://www.patreon.com/universetoday More stories at: http://www.universetoday.com/ Twitch: https://twitch.tv/fcain Follow us on Twitter: @universetoday Like us on Facebook: https://www.facebook.com/universetoday Google+ - https://plus.google.com/+universetoday/ Instagram - http://instagram.com/universetoday Team: Fraser Cain - @fcain / [email protected] Karla Thompson - @karlaii / https://www.youtube.com/channel/UCEItkORQYd4Wf0TpgYI_1fw Chad Weber - [email protected]

In this week's Questions Show, I wonder if there's a way ion engines can give us artificial gravity, if electromagnetic rail guns can launch space craft, and should we be worried about returning alien pathogens back to Earth? 00:22 Ion drive artificial acceleration 02:17 CMB absolute speed 04:55 Magnetic launch system 08:19 What if aliens don't use the same EM spectrum 10:13 Pathogens from Europa? 11:43 Universal time system? 12:51 Secret fusion projects 15:02 What if we find life on Europa? 18:17 What is the Milky Way orbiting? 19:26 How do we dispose of heat in space? 21:18 Higher orbit, slower speed? 23:24 How to judge the speed of galaxies? Featuring a special guest answer from Athena Brensberger at Astroathens. Check out her channel here: https://www.youtube.com/channel/UCdhES1DtY9klIfJsjGKs3gQ Our Book is out! https://www.amazon.com/Universe-Today-Ultimate-Viewing-Cosmos/dp/1624145442/ Audio Podcast version: ITunes: https://itunes.apple.com/us/podcast/universe-today-guide-to-space-audio/id794058155?mt=2 RSS: https://www.universetoday.com/audio Video Podcast version: ITunes: https://itunes.apple.com/bh/podcast/universe-today-video/id794057165?mt=2 RSS: https://www.universetoday.com/video What Fraser's Watching Playlist: https://www.youtube.com/playlist?list=PLbJ42wpShvmkjd428BcHcCEVWOjv7cJ1G Weekly email newsletter: https://www.universetoday.com/newsletter Support us at: http://www.patreon.com/universetoday More stories at: http://www.universetoday.com/ Twitch: https://twitch.tv/fcain Follow us on Twitter: @universetoday Like us on Facebook: https://www.facebook.com/universetoday Google+ - https://plus.google.com/+universetoday/ Instagram - http://instagram.com/universetoday Team: Fraser Cain - @fcain / [email protected] Karla Thompson - @karlaii / https://www.youtube.com/channel/UCEItkORQYd4Wf0TpgYI_1fw Chad Weber - [email protected]

The GRAVITY instrument on ESO's Very Large Telescope Interferometer (VLTI) has seen what seems an impossible sight... The ESOcast Light is a series of short videos bringing you the wonders of the Universe in bite-sized pieces. The ESOcast Light episodes will not be replacing the standard, longer ESOcasts, but complement them with current astronomy news and images in ESO press releases. Credit:ESO Directed by: Nico Bartmann. Editing: Nico Bartmann. Web and technical support: Mathias André and Raquel Yumi Shida. Written by: Ivana Kurečić, Mariya Lyubenova, and Calum Turner. Music: John Stanford – The Edge (johnstanfordmusic.com). Footage and photos: ESO, UHD Team, M. Kornmesser, B. Tafreshi (twanight.org), MPE, F. Kamphues, MATISSE consortium, P. Horálek. Scientific Consultants: Paola Amico and Mariya Lyubenova. Executive producer: Lars Lindberg Christensen.