#436: Cosmic Ripples & Matter Creation: Listener Questions Explored

Hello again, Welcome to Space Nuts, where we talk astronomy in space science, and occasionally we'll answer questions. We get a lot of questions and we talk about them, but answering them that's tricky. But we will attempt today to answer questions about background modulation, also turning energy into matter, which follows up from something we spoke about not too long ago. Spin rates in space? What are they? Why do they happen? Why can't we just have you know, stuff standing still and not taking any notice of us? And a question about moving spacecraft in space, or more specifically not moving them. What happens there? That's all coming up on Space Nuts fifteen guidance in channel ten nine ignition Squench Space Nuts NI or three two one Space Nuts. As when I reported Neil's good, Fred, what's and even Fred Watson is with us again to try and answer all of those. I almost forgot your name, Fred, And it's only been what me is second since we last spoke in real time. Yes, it's extraordinary. We're wearing the same clothes as well. Yeah, I've had these on for four straight days, so I really I can see the problem. Oh, hello, you've got a visitor. I do because it's gonna go out. She's just giving you a wave. Okay, she's just delivering Jordie, so that Jordie doesn't okay, but yeah, people at the window, people at the door, dogs in the lap are Jordie you allow Jordy Hello? Oh yeah. They've got some attentions, not know what is going on, saying what what hang on? What's happening here? Now? My headphones are caught up in his pawse so ah, it's almost like live radio. Well, you never know what's going to happen. What do they say? Never work with children and animals? Children and animals. That's right, It's often true that it is. Shall we get our first question? Yes, that's it before the dog starts, but I don't mind. I like it when he joins in. This question, Fred comes from Craig Professors. It's Craig problem something Maurumbula in New South Wales. Once more, this question is from the SPAN and the Work Department. You've just been talking about the background gravitational modulation of the space time continuum picked up by the pulsar timing arrays around the world. Could these modulations have an effect upon the cosmic microwave background. Could they be the reason why there is a minute difference between the high and low microwave amplitudes? Just thinking about it. If you've got a good answer, he very hopeful. Craig, good answer. I mean put the pressure right. What do you think this is a gee whiz background modulation? Do you want to expand on what he's referring to before you answered the question? Yes, and you put it because I had no idea. No, you put it in a nutshell beautifully when we talked about it. So, so we're talking about gravitational waves, which are ripples in space time itself. But you drew the analo analogy of ripples on the pond. That's right, So running into each other? Hang on, sorry, thanks to these ube have you got to have to do it? Sorr, Just take the handbrake off and let it go. Yeah, well it would. We live on the side of a hill and it wouldn't stop till it got to the bottom of the valley, demolished a few houses. So what's going to happen next? I don't know. Why does the painter need me to move my car? I don't know. Probably wants to. I think he probably wants to touch up a wall that's park next to it, possibly anyway. Yeah, so your lovely analog. So yeah, you've got a pond water, and what we've detected mostly in gravitational waves is things colliding like black holes basically spinning to amalgamate together or lack on any neutron star, two neutron stars, those all create gravitational waves. And you drew the lovely analog that that's like throwing a rock in them in the pond, because then you get these ripples spreading outwards, and that's you know, that's what we measure, that's what we detect with the gravitational wa observatories. But then you said, okay, don't throw a rock in. Pick up a handful of rocks and throw them in. And what you've got now is a sort of background set of ripples coming from all different directions, all different intensities. And that's what we mean by the gravitational wave background, the analog of that in space time. So Craig's question was related to whether that could influence our view of the cosmic microwave background radiation, which is the microwave signal from the Big Bang. It's us looking back in time so far because of the finite travel time of radiation us looking back in time so far that we see back to a time when the universe was glowing brightly. It was opaque, it was glowing. And the bottom line with that is that because the universe is expanded by something like thirteen hundred times since that, the universe became transparent. It's the fog cleared, if I can put it that way. That's why we see this in microwaves rather than in visible light. But what we also see is these tiny variations in the intensity of those microwaves, which is what Craig is alluding to. Now, those are very well understood and are caused by slightly different temperatures in the fireball of the Big Bang, which are caused by sound waves moving through it. It's the bang of the Big Bang. It's what we call baryonic acoustic constellations, which mean sound waves, and they are imprinted on the cosmic microwave background radiation. What Craig has put his finger on is the bit that we don't understand, which is why the picture of the universe that we get, the picture of the expansion of the universe that we get from that is different slightly from the expansion of the universe that we measure today by today's galaxies moving apart. I don't think I think it's a great postulate to put forward, Craig, but I don't think the gravitational wave background radiation will actually influence that at all. Okay, very good, Thank you, Craig. We're getting a few live questions through on YouTube, and if we've got time at the end, I'll jump on those, But timing's a factor at the moment. Text question from John Actually he's got two questions. He said, Hi, guys, you're still the best despite the competition. You're talking about podcasts or soccer. I'm not sure. Just a question or two for your potty, if you choose to use them. Einstein told us that matter is concentrated energy. Has it ever been attempted to turn energy into matter in the lab? I suspect not, But how would you go about it? Yeah, we'll just deal with that one first, and we'll just jump to his second question next. Let's do that because the answer is yes. An experiment done some years ago at a you know, an atom smasher called the relativistic heavy iron collider US Department of Energy, Office of Science User Facility for Nuclear Physics Research of the Bookhaven National Laboratory that actually has produced This is a report from twenty to twenty one, so this is only three years ago. It's basically they've basically demonstrated that you can combine photons and you get matter. Wow, you also get anti matter, and so the two probably annihilated and immediately create another photon. But the accelerator did do what exactly what John is asking about. You take energy and you turn it into matter. Now, it doesn't last very long, but the phenomenon is there, so it is it's usually the other way around that we're thinking of. You know that the nuclear reactions in the sun are turning matter into energy all the time. Tomic energy is doing the same thing. Nuclear weapons are doing the same thing, but we never we tend not to think in terms of putting energy into the form of matter. But it has happened at the Brookhaven National Laboratory, and you can find basically a report on that on the brook Caven National Laboratory Newsroom web page. Would I be stretching a long bow to say, look, it happens naturally on Earth. It's called fretosynthesis. That's a really interesting question because photo synthesis does involve photo quantum processes. But I don't think it's a turning of matter into energy. I think what it is energy A big part of the energy into maout it. Yes, sorry, I think it's quite right. I think it's a it's more like the energy facilitating chemical reactions, okay, rather than atoms being produced it. So it's that, you know, you're not finding protons popping out or anything like that. It's more about the chemistry rather than the nuclear physics of it. So that's idea. But think they actually no, Okay. John's second question is totally unrelated. What makes the Earth spin at such a constant speed? In fact, why does it spin at all? Do all bodies bodies in the known universe spin at constant rates? What establishes the spin rate? So yeah, great questions. Uh, all intents and purposes, it is a constant speed. It does vary very slightly. But it's the reason why it spins at a constant speed is that it's just a big flywheel, you know, which which is is spinning because there's nothing really to stop it. It is losing spin energy and that is going into pushing the moon further out in it's all bit, but that's at the very low rate. What is it the day increases by three milliseconds per day per century, I think, is the bottom line there. So it's very very small. But it's question about why does it spin at all? And do all bodies in the known universe spin at constant rates? Everything spins, and that's because of the way things are formed. Usually when you, let's take the case of a star, you start off with a cloud of gas and dust probably mixed in with it that has it's in motion. It's got little eddies within it, you know, little bits of it are spinning at different rates, but it's collapsing under its own gravity, and eventually, during that collapse, a particular kind of spin becomes the dominant one until the whole thing winds up spinning, and the more it collapses, by the conservation of angular momentum, the faster it spins. And so that's why we've got some that spins once every twenty seven days or so, and the set of planets going around it because they're formed from a spinning disc as well, and most solid objects and even galaxies in the universe formed by this collapse mechanism. So they're all spinning. And now his second bit, do they spin at constant rates? Not necessarily. We know some neutron stars are very very they're spinning, they're very very accurate clocks. Their spin is very very constant. But there is an energy loss caused by gravitational energy actually taking the spin down slightly, so there is a reduction there. So yeah, it's the physics of their formation that establishes the rate of spend. To answer your last question, it's a great question, sad questions, Chardon, thank you for asking them. Very good thanks John, and yeah, I'm glad we could actually nail that one pretty concisely. This is Space Nuts Andrew Dunkley with Professor Fred Watson. Space Nuts. Now, Fred, we've got another audio question. This one comes from Nigel. Hello, fellow space nuts around the world. Hello Fred and Andrew. This is Nigel from Brisbane, Australia. I have a question that is science fiction versus science fact. I've been watching a TV show called The Arc. It's been around about a year now. In it, there's a scene where two spaceships decide to meet up in interstellar space. And in the shot it shows the two spaceships meeting up and they're perfectly stilled. And that's my first question of two inell space. If two spaceships met up, would they be perfectly still or would there be something causing them to drift and move apart? And that's my second question. Is there any energy forces out in interstellar space such as solar winds, etc. Okay, love the show, Thanks for taking my question, See you soon, Thanks, Nigel. I suppose that's reasonably simple to answer, because we send spacecraft up all the time to dock with the International Space Station, which requires maneuvering thrusters, retro rockets, whatever you want to call them. But I'm assuming that he means if they were to meet in space, face to face, no engines or anything, now it came to a dead stop, would they stay where they are? I think that's what he's getting at. Yeah, yeah, probably not really you It's this is called station keeping. It's when you've got spacecraft that you want to remain in a particular position within its orbit. Of course, because everything's moving at least eight kilometers per second, or at most eight kilometers per second in the lower orbit uh, and there will be there will be mechanisms that the cause a drift. So the questions that Nigel's asking the ones that really spawned the Gemini missions in the nineteen sixties, the space missions where the two persons spacecraft called Germany or Gemini, depending on how you pronounce it, tried out the ideas of rondezvous and docking because until then nobody really knew how stable these things were going to be when when they were in orbit. The physics says that it should be very stable, but there might be a slight drift because of gravitational pertivations for example, and also, as Nigel mentioned, the solar wind is a factor in working out whether a spacecraft is going to stay stay put a lot, so there would be slight drifts and that means that you're always going to have to tweak it with your thrusters. That's why the thrusters are so important on rockets. It's actually why the it's not the Dreamliner, it's the star Liner, that's the one. Yeah, the star Liner, I know, it's a Boeing product. That's why the star lineer is stuck up there at the moment because it's thrusters aren't are not behaving properly, or there's doubt that the thrusters might work properly, And that is vital if you're maneuvering a spacecraft next to another one, especially a big thing like the International Space Station. So yes, the entry is it's a trick your business. You can't just park two close together and expect on stay puked. Well, they've always portrayed that well in Star Trek. When they lose all how they start floating away somewhere, so you know, but that would be momentum, I would imagine, But dais. Thanks Nigel for the question. Have you got time for a couple of quick questions without notice for it? Just a couple of quickis? Yeah, I've got a all right, Yeah, this one comes from These are YouTube questions that have been sent to us Live today. Sloth Dad has said us a question. I'd love to know how you got that name. Hi, guys, what are your views on using helium three from the Moon's regular this fuel? Providing we create the technology needed to extract, transport and fuse it, should we be using the Moon's resources or using the Moon for its resources? I regret frong opinions on this. It's a really great ethical question. Actually, yes, and I mean we're going to face it very soon because the the most abundant resource that we can lay our hands on with present technology is the water in the southern polar region of the Moon. We've got evidence and there's lots of water ice there. Who does it belong to? Wells? The Article one of this International Space Treaty of nineteen sixty seven says nobody can own anything in space. So it's a they can earn what they take. Yeah, if you grab it, you can. Where's the line there? Yeah, that's try so yes, So I don't you know, I think we're it's inevitable that we're going to use that water for breathing an oxygen and rocket fuel and the rest of it. Helium three is a step further, and it becomes an even more ethical conundrum because it's potentially a resource that could benefit humankind generally, not just few space explorers. Because helium three, we don't even know whether it's practical or not, but has a certain promise of very cheap and safe nuclear energy by nuclear fusion. That's a long long way down the track the ethics of whether you mine it and bring it back, and you've got to bring back a lot of lunar regulith, the lunar soil in order to get the helium three out of it. The ethics of whether that is worthwhile economically or you know, from an ethical point of view are questions that I think will need to be addressed before we start mining it. So you've raised great question, Sloth Dad, and I like the name too, But at the moment the jury is out a little bit. I think it's inevitable we will wind up using the water though. Yeah, you know, whether it's ethical or not, that's what's going to happen. It will happen. Ethics doesn't seem to get in the way of things sometimes sometimes think it's lost down And one more quick one from Grant. I say space does not warp or bend. With only the matter Energy's frequencies and forces, some not fully understood and others yet to be discovered, give the illusion of space warping or bending. Lo l can't prove can't prove it wrong though, So he's made a statement. I say space does not warp or bend. Yeah, you can, you can, you can demonstrate that space does warp or bend when it's empty, because that's how gravitational waves are propagated. So yeah, you know, it's an object that's responding to that when when we pick up them, pick them up with a gravitational wave detector. But the spaces they're traveling through is devoid of stuff, and it's space itself. The bends as was predicted by general relativity. Einstein was very seldom wrong. Well yeah, and even though his famous predictions or theories he believes are wrong, or one of them specifically, and no one's been able to prove it wrong general relativity, they're still working to break that one, aren't They Just to see whether whether there any holes in it because halls, you know, things that don't work in general relativity, which is so perfect, might lead us to new physics. That's why people are trying to break it. Fascinating. Thank you Grant Lovely to get your question without notice. Nice to get those from time to time. That brings us to an end. Don't forget to visit our website if you get a chance, Spacenut, space nuts podcast dot com, spacenuts dot io, or the two u r ls you can use and have a look around. While you're there. You can send us your questions via the website on the AMA tab or the send us your Questions tab on the right hand side of the homepage. Don't forget our sister podcast, Astronomy Daily. You can listen to episodes there as well, and if you're a YouTube follower, don't forget to click on subscribe and a reminder too. If you want to join like minded space nuts listeners, you can do that on the space Nuts podcast group on Facebook because it's a great little community and growing all the time. I think they've got a few thousand followers now. It's quite extraordinary. Anyway, anyway you can get in touch with us. We're happy to try and help you out with your questions every week on space Nuts Q. And a thanks Fred as always, it's been great fun it does. It's been a good session today and hopefully we'll have another one next week. So let's call it a day and I'll see you then, Okay, Thanks Fred, see you soon, Fred, What's an Astronomer at Large? And thanks to Hugh in the studio for helping out today getting those questions through to us and helping Fred with the painting later apparently, Oh no, I will use now and for me. Andrew Dunckley, thanks for your company. We'll catch you on the very next episode of Space Nuts. Bye bye. You'll be listening to the Space Nuts podcast available at Apple Podcasts, Spotify, iHeartRadio, or your favorite podcast player. You can also stream on demand at bides dot com. This has been another quality podcast production from nights dot com.