Latest / Space Nuts: Astronomy Insights & Cosmic Discoveries / #408: Supernovae Secrets & 3D-Printed Telescopes

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#408: Supernovae Secrets & 3D-Printed Telescopes · Space Nuts: Astronomy Insights & Cosmic Discoveries

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Hello again, thanks for joining us on Space Nuts Q and A Andrew Dunkley
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here your host. Going to have your company and great to get a whole
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bunch of questions in from various members of the audience who want to know about
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supernovae. It's a question that's come in from David and Peter Is because Fred
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Fred's written books about telescopes or one in particular, Peter is asking Fred's opinion
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of three D printed telescopes. That's a new thing. James wants to know
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about the voyage of space probe missions, and Zay is he's come up with
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an interesting idea on how to do particle collision. That's all coming up on
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space nuts Q and a fifteen second is in channel ten nine ignition sequence space
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nuts or three two space nuts as when I report it, Neil's goods and
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back again to answer all of those questions and probably a lot more is Professor
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Fred. What's an astronomer at large? Hi? Fred, Hell there,
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Andrew, very good to see you, looking hale and hearty. Yes,
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I wish no, we're going all right. We're going all right? Shall
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we get stuck straight into it? I think that's a good idea. Yes,
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all right. Our first question comes from David Hey, Brendan Andrew.
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This is David Fellows Flee in Texas. Question about supernovasplodes. Why doesn't it
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blow away the gravitational field? And how does it stay intact to become a
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new front star? Why doesn't it? And it does? Thanks m.
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We've had questions about supernova before and we did actually refer to them in the
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last episode the standard Candle. Why do they not blow away the gravitational field?
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And how does a neutron star developed as a consequence of a supernova?
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Yeah, it's a good question, and you know, we think of an
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explosion as blowing stuff away and gravity is a bit more robust than that.
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Though it's not something you can blow away. It's always associated with mass and
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that's where really the answer to David's question comes in, because what happens when
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a super and over explodes is it's just the outer envelope of the star.
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So what you've got is a star which has got a core where all the
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action is taking place, exactly as our sun has. And then on top
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of that, you've got this mantle or envelope of hot gas where lots of
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things happen. Magnetic fields do their thing and convection does its thing. When
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a super and Over explode, basically the energy of the explosion goes into that
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envelope of material, so it does blow stuff away. And you know,
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David said, why doesn't he just blow blow into dust? And in a
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sense it does. We find all over the sky and there's a beautiful new
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picture of one at the moment called the Villa Super and Over Remnant. We
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find these remnants of supern Ova, which is the gas and dust that's been
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expelled by the explosion. There's a new image from the Dark Energy Camera has
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been released to show what the Villa Super and Over Eminent looks like. If
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if any of our listeners want to check it out, I think you're doing.
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That's an amazing picture. Yeah, just to add to that, one
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of the first pictures of that super over eminence, certainly the first in color,
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was taken by my conic David Merlin back in the probably early nineteen eighties,
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because he was the man who worked out how you could take true color
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images of celestial objects, and that was one of his first targets and it
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is very, very spectacular. The new image taken with a one point three
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gig pixel camera I think shows a lot more detail. It's taken on the
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telescope about the same size actually as the Australian telescope that David used, but
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on a better site. So the detailing very very spectacular. That's not part
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of the story, but that's just to let you know and let David know
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that he can go off and find pictures of exactly what he said. All
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the DU's being blown away. It's gas as well, gas and other stuff.
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But the bottom line is that gravity wins. Gravity overcomes the outward force
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of an explosion and pulls the core of that star down to the size of
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a neutron star, so that gravity is all concentrated, if I can put
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it that way at the middle, and it wins out. That's basically what
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causes the explosion. The fact that gravity wins out, the core collapses,
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and because of basically momentum considerations when the course collapsing, all this other stuff
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is being blown out into space. I used to do for schools Andrew a
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demonstration with a ping pong ball which is very light and one of those really
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solid rubber bouncy balls that bouncees really well. And if you hold the two
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together and then drop them, the bouncing ball transfers some of its momentum to
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the ping pong ball. The ping pong ball flies up, usually hits the
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ceiling quite often hit me in the eye, which always went down well with
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schools. Occasionally hit the teacher at the back of the hall. That went
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down well as well. But it's just that transfer of the momentum, the
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energy from one to another. So I used to say this is the heavy
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rubber ball is an iron atom, the lightweight pink pong ball is a hydrogen.
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To put them together, because they are together, drop them. What
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happens. The iron atom goes down, the pink pong ball goes up very
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quickly. Indeed, it's a good demonstration to do, actually, And so
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that's what's happening. But the bottom line is gravity always wins. And the
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only thing that stops the neutron star crushing being crushed into a black hole is
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the outward pressure of the neutrons themselves, and that's the You know that that
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is enough to stop that gravitational pull. Okay, just as a bit of
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a side note, you mentioned one point three gigapixel camera. If you were
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to lay out a photograph from a one point three gigapixel camera, it would
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be eighty by thirty inches. Okay, yeah, I wanted to know how
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big a photo would be if it was one point three gigapixel. That's big,
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that's too many. Yeah, it's a pretty big photo. I've seen
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them, some of the big photographs put to full size on a computer screen
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and you'll see like just a chunk of it. Yes, I have to
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scroll, stroll and scroll is to get the whole photo. But of course
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you can cram them into the screen these days. But yeah, they're quite
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amazing. Thanks for your question, David. We've got a text question now,
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Fred. This one comes from Peter. He said, I'm new to
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astronomy and just found a three D printable telescope, the Hadley. I've not
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used a telescope before. What do you think about this project? Is it
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a good place to start? Named Peter from Peter, I had look quickly
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at the website he sent about printable or printables dot com is the website,
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but it also shows this printable Hadley telescope. Did you have a chance to
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have a look at that thread? I did yes, it's really interesting.
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Actually so what you're fabricating other mechanical parts, and it actually looks pretty well
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done. It's a modest sized telescope one hundred fourteen millimeters that they're talking about
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for the aperture that's getting on for five inches. That's a usable size and
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it's cheap. There will be a lot of fiddling around with because you've got
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a three D print the components, and there are a few components you've got
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to buy, and certainly the optical components. You can't three D print the
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ips and the mirror of the mirrors, so you can buy your screw and
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mirror kits and you can then do the three D printing of the mechanical bits.
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To be honest, I think as a beginner that you might be better
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buying a cheap off the shelf telescope such as adopsonian, which is the kind
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of telescope that sits, you know, on what we call an altatimuth mount.
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It's just basically a box with cutouts in it so the telescope can sit
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in it and you can move it up and down. The printable telescope is
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that kind of telescope, but you're kind of starting from scratch, and you
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might not really know what all these bits and pieces are for. So my
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estimate, if your a rank beginner, would be to save up a little
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bit more and buy a small Dopsonian telescope, which are very readily available.
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Probably wouldn't cost you that much more than the three D printed one either.
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Okay you are. I was going to suggest that maybe a three D printable
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telescope would be a lot cheaper, but maybe not. But five inch five
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inch mirrors pretty well, lens is pretty Yeah, it's pretty decent in terms
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of starting point. It's bigger than mine for four and a half inches.
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Yeah, I think this. You know, tell uscope making is an art
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in itself, and you're still doing that, but you're just, you know,
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rather than sawing bits of wood up and things of that sort of drilling
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holes in metal, you're actually three D printing. So yeah, if you
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if you're into three D printing, give it a try. But yeah,
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my bat is you'll find it easier to get into astronomy by buying one.
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I'm not I haven't tried any three D printing. My son bought a three
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D printer and used it for a while. And I think he built his
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his son, my grandson a racing car with it or something. But it's
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it's extraordinary technology. But it shouldn't surprise us that three D printed telescopes are
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a thing. Thanks Peter Lovely to hear from you. This is space nuts.
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Andrew Duncley here with Professor Fred Watson. Okay, we tech vote space
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nuts. Next question comes from an old friend, James, mister Duckley Prester
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Watson exchanged from Cincinnati, USA, and I've got questions relating to the Voyager
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mission. I recently read where Alan Cummings, who worked on the mission for
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five decades, said the spacecraft should last one billion years. My questions what
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star systems are the spacecraft going to encounter and how close Where might it end
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up after one billion years? Based on the size, I imagine it will
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be incredibly unlikely any ets out there would detect either craft. If an alien
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version of Voyager came as close to our son as either spacecraft are predicted to
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encounter and other star systems we be able to detect it. Good question.
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Thanks James Lovely to hear from you. You know James has been I was
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wondering that James the other day. I haven't heard from him in a long
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time, but theory is, and I've still got my Cincinnati Jersey. Thank
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you, James. I adore it. Voyages. Yeah, where will they
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be in a billion years if they survive, and it's every probability they will.
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Yeah, that's right, it's you know, i'd say probably longer than
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a billion years. So I don't know the you know, the the exact
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number of objects or solar systems that are on their current trajectories. There are
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two of them, of course, the two voyages. Voyas are one of
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the most distant human made objects, Voyager two not very far behind it,
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but in a different direction. I don't think either of them are going to
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pass near any star systems, you know, within any kind of human lifetimes.
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But because I think their veloses in the region of twenty kilometers per second,
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and well you can divide a billion years by twenty kilometers per second to
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get how far they'll go, it's still within our galactic neighborhood. But I
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think the more interesting question that James raises is could they be spotted by,
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you know, somebody on the planet in extraterrestrial intelligence on a planet as these
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things drift by, and the answer is yes, they could if they were
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near enough to the Earth. Both the voyagers would be detectable from Earth.
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If they were whizzing through our solar system, it would depend on the trajectory.
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If they were on the other side of the Sun, we'd never see
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them. They'd be too small, you know, they're just a few meters
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in size. But they will shine by reflected sunlight or in the case of
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the Earlien version, reflected starlight. And if you've got big enough telescopes and
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you're sufficiently adept at scrutinizing the sky, you might well see them. And
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then you might do what we'd love to have done with the interstellar asteroid chase
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after it, with rockets or laser propelled sales with cameras on board, just
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to find out what it was. So that's I guess the old thing at
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fate of the voyage of spacecraft is maybe to be captured into orbit around another
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star, maybe to collide, although collision, because space is so big,
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a collision is actually a lot less likely. It's more likely that they might
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be captured and maybe even spiral in towards something down the track, which I
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guess will be a collision, but we don't know. And that's what makes
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them. I find them completely intriguing, these voyagers, and in fact the
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other three space that are leaving the Solar System, because they'll probably outlast our
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species. Uh and yes, effectively go on forever they've you know, they
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will they will keep going. They won't keep operating. The nuclear batteries will
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die, but they will be still artifacts on a trajectory away from the Solar
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System. Yes, And of course one of them is carrying that recording of
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the sounds of Earth. So the two voyages, yeah, they both got
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that. Yeah, all right, I didn't read one interesting Oh that's right.
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Yeah, I did read one interesting theory is that they could reach a
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star that doesn't exist yet in one or two billion years, So you go,
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yeah, that's food for thought. Yes, indeed, so there's there's
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all sorts of possibilities. Could they you know, is it possible that one
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or both of them could be captured into a planetary orbit. Yes, and
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when we've captured a couple of pseudo moons, haven't we. That's right.
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That was one of the outcomes that I mentioned that I probably didn't say it
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was being captured into an orbit. But that will be what would happen,
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and it's captured by the gravity, and it would remain in orbit, maybe,
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as you say, forming an artificial moon of a of a distant world
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around a distant planet. Wouldn't it be amazing if it just happened to stumble
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across an occupying planet? Yes, yeah, yeah, And they eventually achieved
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space travel and went up there and went, hang on a minute, what's
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this? What is the first? Yeah? Yeah, I never say never.
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Thank you, James. And our final question today comes from Zaane.
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Hey, space nuts, this is a name from Moment, Australia. I
16:52
hope everyone is doing good. I've been listening for ages. I love the
16:55
show. Now I've had this idea of the years and it's on the topic
17:00
of particle gliders, like a large hadron glider, which, don't get me
17:04
wrong, is an awesome piece of engineering. Also hop it we build these
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things in space and from what I understand, the particles are guided along their
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journey by electromagnets and I'm guessing the bulk of what makes up these machines are
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those super conducting electromagnets and that would cost a lot to send up to orbit
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even once starship is up and running. But would we even need them?
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Couldn't we just shoot these particles off in opposite directions in the same orbit and
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wait for them to meet up. And I guess the speeds with forests like
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far exceed the scapebod see if anything else all system. So I suppose we'd
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need to do it around something really big, black, hot, or something
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might of the wait a long time idea. It's an idea, and I'd
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love to hear what friend Andrew you boys have to say that. So have
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a good one. Thank you, Zay, and thanks for being a long
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term listener. By the way, particle colliders, okay, we've got Yeah,
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we've got the large hadron collider on Earth, and I think they're building
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a bigger one. They've fred but taking it off shore, you know,
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maybe using the planet as a particle collider, using the natural gravity effect.
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I don't know how you would target something so minute in opposite directions to meet
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on the other side with precision. That's the that's the quandary I find in
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this question. Yeah, there's a number of issues. Zam's right though,
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that a large children collider is it's us quite modest in its size. The
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tube is about a meter across, which is what is it twenty seven kilometers
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if I remember rightly, around the perimeter of the of the large Adrin collider,
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So it's a meter that that contains the electromagnetics and cryogenic cooling liquid even
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liquid helium. I can't remember what the coolant is, but all that those
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magnets are exactly as Zaine said about precisely guiding particles along around the accelerator.
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So that guiding has to be very, very precise. And you're right in
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what you said, Andrew, in that you know, the precision that you
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need to get too protons to collide is pretty high considering how small they are,
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But the problems bigger than that. And Zen's actually hit on it the
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figure quite a lot of times. It's been at the large Hundrd collider,
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but I've been there several times and in fact went down into the bowels of
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it to one of the detectors, the compact new on solaroid, where you
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see the ends of these tubes that do the acceleration. The velocity is if
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I remember rightly, they're accelerated to ninety nine point nine nine eight percent of
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the speed of light, So they're traveling at the speed of light, so
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they're above the escape velocity of anything that you could think of putting at the
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middle, with the exception of a black hole. As Zain said, we
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know that black holes do focus the light around them. They actually, you
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know, the light travels around a black hole because of the gravitational distortion of
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space. But you're not trying to make particles collide around a black hole.
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So maybe with a black hole it could be done. You've still got the
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difficulty of getting one particle to hit another by the end of it, by
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the end of its orbits around the black hole. I think it's going to
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be much easier and much more cost effective and much more realistic to keep doing
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things here on Earth with our standard particle colliders guided by electromagnetism. Indeed,
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yeah, I like his idea, and maybe one day they'll find a way
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of doing it off the planet. At this point in time here probably beyond
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our capabilities and certainly beyond our bank balance twenty six point seven kilometers the larch
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hedron collide said twenty seven. So not that rounding up is always a good
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thing. In astronomy unless it's the hubble tension. Andrew, if you're around
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those numbers, they both come out to seventy and the hubble tension disappears.
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So wheneber you hit you fit on the answer. That what we were talking
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about last time with the tension. Yes, thanks to your question, Zaan.
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Always good to hear from you, and a reminder, if you do
22:04
have questions for us, please send them through via the website. We always
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love to hear from you. It's a simple process of jumping on to space
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well. We do love to know where you're from. So yeah, send
22:45
us your questions. We will try and answer them in our Q and A
22:48
episodes every week. Fred, we're done for another another day. Thank you
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so much, it's a pleasure on you and I look forward to talking to
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you next time. Indeed, Professor Fred Watson, astronomer at large part of
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the team here at Space Nuts. And thanks to all those people back in
23:08
the studio a number one named Hugh for helping out as always, And from
23:15
me Andrew Dunkley, thanks for your company on this edition of Space Nuts.
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We'll catch again on the next episode. Until then, bye bye. You'll
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