Latest / Space Nuts: Astronomy Insights & Cosmic Discoveries / #436: Cosmic Ripples & Matter Creation: Listener Questions Explored

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#436: Cosmic Ripples & Matter Creation: Listener Questions Explored · Space Nuts: Astronomy Insights & Cosmic Discoveries

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