Dark matter is the longest unsolved problem in astrophysics. Find out what we know – and what we don’t – from your own personal astrophysicist, Neil deGrasse Tyson.
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Skip the commercials support star talk on patriarch to listen to every episode, commercial free. With this, is filled with secrets in industries leaving us with many questions to be answered. We find ourselves searching for those answers as the very fabric of space science and society are converging here for the first time what what the Japanese it's easier I mean the brakes daddy, you Glinda did you grandma ass, the brain they get lab, like what
this is STAR Talk, Neil the Grass Thyssen, your personal astrophysics, and this is the cosmic queries addition I have with made Liane Lordly an unwelcome bad things. On me. This is cosmic wearies. It's not your first rodeo here not experiencing like you and so remind some listeners, perhaps for the or tell you for the first time we in the cosmic queries additions. We solicit questions from all of our web presents her. Are social media presence? and a comedian. In this case. You call through them.
Just send them my way. Yes, and so let's go ahead and do that an end, and we need to remind you that you have not seen these not ended. The pointed out to stump mayor, and just I haven't seen them so they're. So if I don't know some I'll, just tell you, you notice, make it ok, you pass our answer. Work, agrigent astern, where you get so. What are you? Ok as disappointed potpourri means without one subject are always just on all the universe. We are, I guess, discussing dark matter and dark and dark here all the time, and I am and I'd efforts took a personally until someone said: no we're not talking about it. So I watched in is Brahma Rocky CO, Frank, and only that's cool. Maybe it is a bit is critical and I actually now note that he or she is that what through what the social media sources
I believe this is from Facebook Facebook, because if it were a twitter road building hundred forty characters to no longer go fell short question. Ok, I've seen graphs in her percentages of what makes up the universe somewhere around eighty percent dark energy, sixteen percent dark manner and four percent everything else? My question is: how did we come to these numbers, What instruments were used to make that conclusion nice? Well, first of all I mean dark matter is weak, most of the gravity we measure in the universe no known origin, everything we we know that makes gravity like matter and gas. Odds in energy and all these things he added all up. It doesnt account for the gravity we see. So that's like that. So this missing stuff there used to be called missing matter
I used to be called that we say miss out. You know it should have been there in the first place. I so it's really it's really too much gravity is what we should call it not missing matter, because maybe gravity comes from other kinds of things: So you can add up how much of that is driving the universe, smoking right and put put them in a box, and then you say: hey the universe, monster to sort a slow down in its expansion, because this all this gravity. Yet it's accelerating in its expansion, the some mysterious pressure in the vacuum space. Pushing on the universe that takes a certain energy to do, and you put net put that in a box you. Those two together is ninety six percent of everything that matters no pain tended, ok and so everything we know all of our laws of physics off of our understanding of the behaviour of matter motion and energy is four percent of the universe. We understand we understand four percent of the universe of women
driving universe it s the charges pie, chart it likes, cutaway, four percent of it upon. That's all you got that's all you got in there. We know it's there and that one of the quest was how do we know how we had it gets me? You can measure how much gravity is out there. As you can see the motions of objects and you can see how fast, for example, we are orbiting. The center of the galaxy is: do you just met for that. We can do that and I have rejected the but, of course, and which When our fast we're going, you can say well how much material is between in the center of the galaxy to enable us, Go that speed this these. Two very related numbers, the Maghreb and the amount of gravity pulling on you and how fast your going in orbit. How can those that their connected in a single equation? you calculated up. You say they should be this much gravity down there and you can
all the stars and all the gas has all the black holes. Everything- and you cannot account for that much gravity, so there's too much gravity list is a too much gravity problem, that's right has very core: that's how we measure that now, the acceleration of the universe we have, Super Novi the stars blow up at the end. Their lives and their so bright. They shine the entire galaxy in which their embedded briefly like for about a week. So that mean galaxies really really far away. If one of these supernova blocks eight, we just we just saw you. That was ever minutes where we was there, and so you have- and we know how bright these soup, There should be a luminous. They should be at a given distance, ok I should like a hundred like all put it a mile away. I know how dim net should look. Ok, my way, half a mile away right in front of your face. You do this with supernova. I know what right have whatever distance we find. I know what it should be when you do that. What you find is that the these
distant. Galaxies are accelerating away from us accelerating away I get it just because they so so so that These are like a standard candles as this, if in expression we need to hear much anymore, but it's it's the metric that we use to know how far away and object is how damn the supernova and of and so on, may it all out on a graph. We find out that where it is versus how I been traveling who don't match up, and so they had to be exaggerating to get there, and so you annulled with. We only know fork so dumb, stupid ignorant about most of the universe, which is really cool, keeps Ashraf physicist employed. Shows called start out loud the long answer, but that's not only our stood out in their did that you condensed it so well that that's an entire semester for some of you have actually yeah sure ninety six percent, the universe put into three minutes. Well done only our personal astrophysicist can do that. I was
of related questions from Jean O Donnell, who discovered darkness and I know it wasn't AL gore- Sorry just voted on the internet on on the on that. Only in this dark matter was discovered in the nineteen thirty's by Adieu named Fritz Wiki, not friends, that's totally for its dirty party window. He had time to discover dogmatic, that's it was always at a party, so he was. He was Swiss born American if he was ever naturalised, but his whole professional career was in America and he worked Caltech in Pasadena, California, the California Institute, of technology and he was measuring the movement of galaxies and I'm the example. I just gave us with the sun Our solar system orbiting the galaxy. He did that same measurement for galaxies orbiting one another in a cluster. Galaxies so he's measuring how fast these galaxies are moving and says that speed
moving tells me how much matters be their right to account for the gravity and he does the calculations and he's off by a factor of five or ten right, any child double checks and triple checks. As calculations gets the vacant, you really don't match, and he said this missing matter somewhere and its it was the beginning of the missing mass problem today known as dark matter, and there you have- is Fritz Wiki items. Nineteen thirty fix seizures covering a math era is what I want. That when we come back to start off the cosmic queries Edition.
Breathing space inside it down to earth you're listening to start we're back on its cosmic queries. Additional. I got Leon bordered with me hungry. You know we're earlier on this, but already my head start new sectors I'm trying to wrap mom lines around dark matter, dark energy, less might an animal rights for its rebate ended target for Mr Wiki, I'm sorry, let me be respectful, MR so we could be. Doctors repeated on doctors, answers for its Ricky, discovered, dark matter, beckon back, then it was called missing. Mass, it was, of the missing mass problem. Ok and it's the longest answer the problem in modern astrophysics, what women are thinking than real. Ok,
No, that would be a longer price. You know a related. Can I give a related commented if I may to show so yeah? Ok, the study of the universe is the second oldest profession. Sleep so young. So lately both of these challenges go way back. Ok, so, but the efforts Wiki was acquitted, colorful character and with a name like that, how could you not be and he was cantankerous and the scream at you and pound the table feed in agree, but it was brilliant and he was he predicted the existence of pulsars, which are rapidly spinning balls of neutrons and so we should columns Wiki stars really in his honor I like it, but then they would later be discovered and he had predicted them based on what he had just learned from the newly invented branch of Physics, called Quantum Mechanics sets Fritz wicked cool out.
Because he couldn't figure out women egos. Forget it, I'm gonna figure out the galaxy easier. So what else you George? This is giving you a headache. We'll try to lift me. No, no! No! It's it's! You know. I know when I M playing outside of my intellectual dams, and I am not afraid to it- will make it part of your depth so we're that's. Why Breyer, I'm seeing these questions. You got a lot of our social media. Yes, while our next question is from Andrew Schaefer and at its similar but but different, I guess of a kind. It's hum how much dark matter or dark energy is pretty did to be in the universe, ass. Well, so the number that we put forward while sofa enemy, backup we measure tough line, so it turns out when we try to make galaxies me on a computer.
To say. Did you just let me in on some top level stuff in that I have not read the hearing. We have promoted slipped out, german and Dutch. It's coming and gentlemen. What I didn't hear anything look at this light so we are so the it turns out before we understood how deep the dark matter problem was. We had a hard time making seize on a computer, you put in matter, you spin it up. You see if Greece itself gravity cause matter attracts itself. You watch the computer, provided all your formerly are accurately captured in the programme. Newtons laws of motion in differential equations. That where things move, and you put it all in there you loaded up and we found that we can't make galaxies. Not only that, we can't make the structure of matter in the early universe, unless we put dark matter in the equation, says something missing:
something was missing, and so not only does the universe show us, it has dark matter. We need it in our formulations of the universe in order to create a universe. It looks like the one that exists so We have good steer radical confidence as well as observer mission requirement. The dark matter is out there and we. We think that that missing thing is dark matter and not love me. I love to make a universe absence of not too much love it's too much more gravity than we can account for looking there. It is so what else you! I had a question from Robbie Jager eager everywhere from it source Robbie does not identify where he or she is over. So it might be a wooden spoon, one thing that still has an quest for knowledge. I have heard that dark matter and dark energy. Make up the majority of stuff universe. Is the mass of all the blood
holes within galaxies figured into this calculation of stuff up black holes are ordinary stuff yet their exotic for in our lives, but for this four percent universe. We we got all the black holes, but I promise there are in there. We told me little four percent of all things that we get out of the apple pie slightly financial year. So that's why dark matters is really not a good term. We should just really call it Fred because because renaming dark matter, because we don't know that it's matter are we joke, I dont know so to call it that already, it puts a bias in the expectation of what you would find and that's not good science. So it's really just. We have no idea what it is and call it something that doesn't make you think anything. I just call it Fred, so ok friend,
I'm. I'm sorry. I would love to know who you think Ethel s already. That would be dark energy for threatening to frighten red, never go. We know what this actually. I dont see the question here, but I mean I was looking. You can enter your about what you know that someone and ask that question. Apparently, those which has placeholder names, the other place, orders that's why so manner incorrect as black holes are dark and their manner, but is there not dark matter? That's the thing So that's why dark, Maria and really art and their matter, but they're, not dogma, And now this is: u alleviating my head. I well, I can say more their dark there, if matter and they matter, but they are not dark matter, I mean you really are very clear for hours. I would also got Chris Butler and Chris says when I first heard a dark manner or energy. I had the thought
I might be from the visible matter. We know of being pulled into black holes and somehow was turned into dark matter energy, because all that matters to go someplace right, what we do, one thing, if black holes ate their dinner, and then spewing out someplace else in the in the universe where, in the galaxy black holes had a digestive tract digestive tract venue can think maybe they're turning it into dark matter like black holes at dark matter, machines, life, but the here's, the thing everything they eat remains concerned and within them, so you can see as they eat. They have more and more of an effect on the passing of stars near them, and so the buckles have this huge sources of gravity contained within the weak. Understand that we got that That's not mysterious to us not only that we better, supermassive black hole in the centre of our own galaxy, the milky way and other galaxies have, like others,
supermassive black holes, a billion times the mass of the sun, and he said: hey every accounted for that sure, go ahead and account for it, but the mass of the galaxy, Tough is like several hundred billion times. Ass the sun, so I the one supermassive black hole in its like several hundred billion and one So it's big as a solitary thing, but in the scale of the of the galaxy it's just that it does have its big to us, but not to the universe, not back to the Galaxy Galaxy right right. So, even if we have neglected to count, the black I'd have about the black more anybody's, but we need to take this opportunity to start at one exactly we, even if you forgot them everything we know about them in their frequency and the likelihood in the galaxy we got em all night. I do have a question by something that you said that things enter black hole, but they don't leave there, sir,
Not really I mean they sort of leave, but not really I'm imagining that the black hole needs like a mass of Super comic or something that, because one should blows, it's gonna be off Everyone Koane word, I'd, never think I'd ever use that word and astrophysical conversation, and that's why I'm here? This is what I bring that there be a great new storefront black hole collapse. That they would win in the Cologne ex contest? I should see that in an episode of doktor, who I feel coming so black holes beat things and as we know they stay right there down in their centre, but over time the black hole slowly evaporates these particles and hawking, first figure this out and is named in his honour, its called hawking radiation, and given enough time these particles inside the black hole will evaporate from just at the border of the event horizon. That's the place beyond which
you dont return, but I slow and all your items. They come out one by one overtime, very slowly, So it's an evaporation process and it comes from a quantum physics- is a quantum physics phenomenon actually, and I get adamantine. Ok can get in the next thirty second, because we have to go to break in a moment. Okay, so I tell you hawking radiation in thirty seconds, ready, lady, ok, so you member equals She squared, of course, see equal energy is what's the matter? so on the outcome I'd edge of a black hole? The gravitational field is so strong. The gravitational energy is so intense. The gravitational energy becomes matter right at the outer edge of the black hole in that matter escapes so the black hole evaporates because its gravitational energy is getting converted in. Matter, and you know something those particles that escape invented out of the you must space itself have the same
women, Tory of all the particles that went in in the first place. The black hole did not forget what it had eaten use in industry talk. Ready will be back in a moment, have terrible secret for you. I'm gonna considers singing all of the ads on this shell, there's just one. And where to get out of hearing there go to patriarch arms last star talk and support. Where does at the five dollar level or higher to listen, the star talk ad free you can download all current episodes into your favorite podcast player and never
we're here, another commercial on star talk ever again. You will definitely not have to hear me saying if you support us at Patria, dark coms. Last our talk, radio, I mean I'm just thinking I mean just saying This is starting to see the evidence. Of this star talk radio, because cosmic queries addition and I'm your hosts meal, the grass Thyssen astrophysicist at the American Museum of Natural history and I host STAR talk Leon. Lordly am yeah. Thanks would be a non starter. Thank you. For having their value on Twitter, Atley, Hannelore Leon loyally? I e g h, an unknown in the world spells now do not yet have scant will create a year ago
but you're, reading these questions. For me, I haven't seen them and withdrawn dark matter. Dark energy, ok, ass! I have to say I am very impressed with start heartlessness in fields. These are some very wicked awesome. Listen, we have awesome, listen now exists and buried, loaded and cogent, firm, learned folk, and to that end I have a question from a whim Flynn, and he was now, can you discuss how the experiment on the eye assess may have uncovered hints of dark matter, and why a dozen interacts with ordinary matter. Why does it matter? you don't understand. What's the matter right, sir There is an experiment on the International space station ass. He was using the review of the angolan area now it for It has to be a principle word though, is not an acronym its then a review abbreviation. We are social services.
Stifler NASA is an acronym scuba is an acronym. Laser is an acronym later an acronym, oh yeah, what's in a name the light amplification by the stimulated emission of radiation. It sounds really dirty Can you say that is the city please not? Finally, for the light amplification by the system right that's so that sets laser. So those acronym halcyon em, like pseudo named name, is a name, I guess and latin or something so yet so
the night was too much to us. Why? What we got no lands? I'm not joking! We can discuss how the experiment, but we are on the I s- ass, yet not an acronym international space station, so international space station, as you know, orbits outside of earth atmosphere, so their certain particles that come from space that don't make it to earth surface. So you want to study them things are don't make it to resurface. Inhabitants are most ultra violet light. Hitting the earth pitting earth zone does not make it through the atmosphere. So when people, you're a tan or get burned or darken from the ultra violet light from the sun. That is a tiny fraction of the ultra violet light is actually hitting earth. Most of that get absorbs, gets absorbed up there in the ozone layer, which is why we need the ozone, but that's a holiday.
Joe, so the international space station is above the atmosphere, so we can see things detect things that never reaches earth's surface, among them a very high energy particles flying from the centre of the Galaxy Nicole Cosmic rays. Ok, that very high energy higher energy. Than any particle accelerator we have ever created here on earth. Nature is the biggest atom smasher there ever was. Nature smash smell, so I just got fired solve this. I think it's the if I remember correctly, and an alpha proton x, Ray spectrometer on board the international space you shaking her head. Like cartoon character. Taking, I just got hit with a, although particle in resolving some of the bad manners utility about. No, not the awful proton x, Ray spectrometer Batman right. So it's it's a device that can measure the energy of high speed pie, energetic particles. Basically we can, we hit me,
but we can measure it knowing exactly we can't make these particles we block, so accelerators aren't powerful enough. Now there is a hypothesis that dark matter actually is matter, but a matter that exists only in very high energies and high regimes of energy It's a whole other set of particles that are perfectly fine existing, but don't interact with our particles, parallel particles. If you will, we always goes a racist. What cover, and so the existence of these particles has suggested as the point of origin of dark matter and so you wouldn't see them cause they don't interact with our light. They don't give off light that we know of or can measure they would have
gravity. Ok, they would be so to permeate the cosmos. Through these you know, through these mechanisms and so there that would be a in a policies, and it was a detection made just recently, which is why the question was for sure who some as also on top of current events, that's hinted that a dark matter particle was discovered on that detector on the international space station above earth atmosphere. So many well spent but three billion dollars a year me. What's what what's the universe worth to you I wasn't prepared to answer your questions today, can I get a coupon you're, not gonna, for the entire universe, Algiers arrange generally misplaced, her finger, you come back later with a response. So what else you get older, quick question with found evidence of dark matter. Does it changed the field of astrophysics? In any way? Oh, you well, yeah. That's an easy question, I'm sorry! If the new doc, if this new particle is this
course of dark matter. Then dark matter is matter right eye, for Saint early Euralia as it might not be monopoly, might be? Somebody doesn't have no idea what it is. It could be like regular matter, regular gravity from another universe leaking into our universe, and who knows right? So if it is it tightens up our the wild ideas like what it could be. So it wouldn't change how we conduct business, but it constraints. How science fiction you can get by trying to account for it ok and your size friction, but for an instant later, apparently you're a and as well yes reminiscent under a ago when we back more start, talks cosmic queries addition here with landlord, see in seen a moment,
beg. Unlocking the secrets of U world and everything orbiting around it stereotypes not bad at it. Alien agreed by another people, gotta get up a damp adjust to go back to the gave way and above this star talk, I liked you think it really is the after hours addition. But it's gonna start talk cosmic queries and I have two dark now, because the universe is dark soap, it so the universe in the dark.
So the acoustic united. Just as an earth thing, you know, I wasn't value, don't that's on earth and waste my time, solar threat. So we could we solicited quest. From our readers and fans and everybody to ask about dark matter and dark energy. Beyond the news I mean you ve been asking them so fire away Yes, are these questions are from Facebook. These folks are really as step in and what some great questions and this I'd love us on this next ones. My favorite almonds from Anthony dilemma. If from pronouncing that correctly and very specifically its from the dilemmas period, five, great science class at Cedar Middle Cedar Middle School in his superior California exactly where you are kids now the question is: would it be possible to capture and contain an amount? of dark matter and be able to study it in its purest form, so these are middle
These are middles, so the Mount Athos restore hormones haven't kick in your apparent or are we ran a lucid moments in between harmonic fluctuation? So that's a great question because, scientifically to study anything you want to bring in the lab and help it in turn it and twisted, and heated and cool it. I wait not science or dating from computer? Now too, astrophysicist. In that sense, we are the humblest of all sciences, because we do not control and manipulate are subjects. We cannot take the black hole, we view and bring it into the lab, and- it pocket cares little eat you carry over. So it is a it is the gentlest humblest of all disciplines well amble in talking about its assets gain while I'm in so
One of the other challenges with dark matter is, you can contain it. You know why you can contain it. Does interact with our matter, and the non interaction part means you can put it in a box, because a thing doesn't even see your box. If it saw your box, the box might contain it dark matter, permeates all pace and all matter. Ok, how you, knowing it but we measure its gravity We know that is gravity. Is there so what we might It is some kind of a gravitational bottle I wouldn't know how to make one looking, but the same challenge arises with very high temperature plasma, not blood plasma. This physics, plaster physical, pleasant, very hot gas by the sun, is above all a plasma right right or wrong. The northern lights. That's plasma right plasma is that a lot of in a very often seen walking down the street, but plasma is everywhere in the universe.
Plasma is so hot dog, I, like in the center of the sun, is so hot you carry that around it. Vaporize is any ain't you put it in. So you need us I shall container in the best way we know of is a magnetic bottle. Ok, you create a magnetic field in the shape of a bottle, put the plasma in it. So it's not touching any matter. Otherwise it would have a prize. The matter collapsed, touching a field, sir, with dark. Matter? We would need a dark met. We need something made. Dark matter on one side and made of regular matter on the other in the line. Or something so bad. It doesn't pet penetrate that member, so you can carry the thing around and bring it into the lab. But you know the biggest problem dark matter. And even interact with itself LAO. So we get there,
what's the matter dark matter? Want you talking to himself that's gonna zone with regular matter. We know we interact with ourselves because we can collapse and mix all objects. What is a solid object, but a collection of atoms that got to know another and are stuck to each other like merits. So we and they feel percent of the universe that is matter casually. Create solid objects. Ok, as far as we know, dark matter cannot create sound option. Because it can interact with itself and stay stuck to itself, so that eggs containing it and studying it in all the traditional ways, a challenge: ok, well so shorting his cat, not darkness not dark man, so we gotta go four minute what it would also Gallagher. I like answering questions in sound bite me. I love it. Ok is well from Robert Tallow is dark matter. Convertible too dark energy, as regular matter, is convertible to regular energy, nor their complete. By far as we know,
as far as we know, they have nothing to do with one another. Maybe this is where the naming becomes a probable here's, the thing imprints If energy can become anything right vehicles empty square, who says that here we got diversion Maybe I can take our energy take our matter. Could in its energy and internet energy into dark matter, I think in prince Will you could do that, but I dont know how ok that's honest yeah, so When we come back, we will enter the last segment of cosmic queries and it is the lightning round be there.
The future of space and the secrets of our planet reveal. This is start. We're back start off after hours starts work because we could In addition, this is the final segment of the hour yeah and it's the lightning round, Don't don't because we give so many questions. I gotta we gotta do where I give you sound bite answer. Yes, all right. So let's do various eyes landlord and now this question and went into this passage from Patrick Side like any says how to duck meadow come into being after the big bang. We have no idea next, Wow jelly sellers is dark matter, energy. You know everything will work, but we know the dark matter. Was there from the beginning? I hate with. We know it's been there from the beginning,
but we have no idea how and why it came into being so you have to the Bell and because you enlightening that question Bernardo Joey's, I just want to know is dark matter. Energy increasing as the universe, expand. No dark matter is, as far as we know the same in its proposal as it as a friend of the total gravity in the universe. That's the same and gravity stayed the same, so we're fine at Kay. Casey Wheeler Becker wants to know how this dark matter influenced time, dark matter Like anything else, in the universe that contains Energy Einstein, special, really theory of relativity as the time slows down in the presence of high sources of gravity, and so, if you have region where there's a lot of dark matter. If you can find a place near that dark matter, that is high gravity from that dark matter. Your time will take more slowly. Capitalism will metabolize less quickly
not going there next Larry below my wants to know of dark matter does not interact electromagnetics with ordinary matter. How does it exert its end on the atoms and particles that make us it does mark influence any light. You cannot see it because it doesnt either absorb reflect refractory disperse light. So there that's as dark as you can get in line, does not even know it's there, but what white does not the same thing as gravity. It's got gravity. We can talk about grand old, I'm talkin about light and it's got gravity and we feel it what would happen if all the dark matter in the universe suddenly vanished. Awesome question if all the dark matter vanished, our Alexey would fly apart because all the speed of orbits that all the solar systems have is the right speed for the regular matter, plus the dark matters gravity to contain it. If you'd instantly take away the
dark matter. We fly way in all the orbits go cockamamie and Galaxy clusters fly apart and everything goes haywire well, and I don't get this Ok Robert a tower wants to know. If the Higgs both on gives master regular matter, does it also give master dark matter, go robber, verse. I dont know the answer to that question, but I would guess that particles, if, if the Higgs, both on which interacts with our matter, could interact with dark matter then we'd be interacting with dark matter. The suppose on I'm. Judging this I mean I got people I can call on this, but we got people so so so the Higgs both on is talking to us, and our kind of matter no dark matter. Ok, just like that, unring annoying dark matter might have its own, who expose on I'll see, you never gets and would not be called at the Higgs, both on bar
while they expose on high and that's what they're talking about your guy Next Jesse Turner wants to know, could dark matter and gravity, be anything like the North and South poles of magnetism, like the opposite forces, in the universe, refusing to reward the good and evil and the up and down back it's unlikely. Because this six times as much dark matter as there is regular matter rather there's six times more gravity about which we, oh, nothing. Then there is gravity about which we think we know everything, and so, unlike magnetic pole whether equal opposite these make them. These may be opposite They are certainly not equal rights. Oliver Gibbon dinner governing How much can we learn about dark matter with gravitational waves detectors like Lego and LISA, nothing or what are its russian? Now? The problem is the gravitational waves detectors. Lycosa laser interfere metric gravitational observatory.
That would be a wine glass. This thought. Okay. So why goes a great big, physic physics, experiment that is looking for ripples in the fabric of space time caused by disturbances in the food distribution of matter in the diverse matter can get collapsed densely enough to create a ripple. If you're spread out, like dark matter is not making ripples. Ok right! So everything no about Lego, tells me that is going to measure our matter. Not there's gotta rigid Smith from Frisco, Texas love. It but ways might dark matter affects the rotation of galaxies are what Morocco we hinted that earlier in the show, dark matter enables galaxies to rotate as fast as they do. Ok, appearances and the mismatch between what pulls the grant the what Poles on the stars and speed the stars are going through. That was discovered in eighteen. Seventy six by very Reuben she's still alive
a senior astronomer and astrophysicist, community culture. We discover that nineteen, seventy six galaxies needed dark matter as well. I think what did you want more and we gotta caught Brandon the dogmatic gravitational pull and we don't see it could hinder space travel outside our solar system. No because it's so thinly, spread across the galaxy, is all around. You know it's not in the way we and we get a wrap. This up. We do not start on radio and I'm on your list of very funny, lady it I can get to know where you perform as you travel the countryside. This has been brought you in part by from the National Science Foundation. I knew the grass taste in your personal astrophysicist bidding as always to keep looking up- dial up,
like Galileo job the orange wish. You could listen. The star talk, commercial, free, joint startled, on for as little as five dollars per month and the ads will disappear, learn more at patriarch dot com. Last star talk radio,
Transcript generated on 2020-01-25.