Astronomy, Science, Space, and Stuff.
Space Nuts Episode 250 with Professor Fred Watson & Andrew Dunkley
RIP Michael Collins – friend of the show
Astronomy, Science, Space, and Stuff.
Space Nuts Episode 250 with Professor Fred Watson & Andrew Dunkley
● RIP Michael Collins – friend of the show
● Questions from our listeners – Cassandra, Ryan, Graham, Paddy, Alyssa, Ralph, Andrew and Mark. Fred has answers for all of them,
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Space Nuts 250 AI Transcript
[00:00:00] 15 seconds guidance within journal and nine ignition. Think quenched
three, two nuts as the magic word. It feels good. Hello, once again. Thanks for joining us. This is the space nuts podcast. My name is Andrew Dunkley, your host, and with me as always is astronomer at large professor Fred Watson. Hello, Fred. Hi, Andrew. Very good to be here. I'm always glad to see your smiling face.
When we kick off with her. A space, not it's recording. Thank you, sir. And congratulations, episode 200 and manual of 50, who would have thought it? I, when we started, I did not know if this venture would turn into anything and I'm just. So stand and, and, and, um, humbled by the global support that we get. Uh, it's, it's been a real joy [00:01:00] to, um, to, to, to connect with so many people, not only via the podcast, but via social media and to be able to, um, swap messages and jokes and, and just learn a little bit about the people who, uh, who, who.
Love astronomy so much. And, uh, it's, it's a thrill and of course we're not stopping now. It makes it sound like we're, we've come to the end, but we haven't yet. We'll keep on keeping on to a thousand. When we get to episode 1000 or 500, I think by then, they'll probably be digging us up to see if we want to do any more.
Speak for yourself. I'm Helen. I've just spent a lot of money on my teeth and my knee. I want to get good value for it. And I just built a putting green and I know you use at least 30 more years. Yeah. I'm sort of wasting money. If it, if it's going to sit there and look full on [00:02:00] today, we will be answering audience questions.
That was the original plan. And we've got questions from Cassandra, Ryan, Graham, petty and Alyssa, Ralph Andrew, and Mark about all sorts of subjects. But we had one interesting combo question from two different people who don't know each other, but they both sort of asking the same thing. So we're going to do that as a single double question.
Don't ask me how, but we're going to we'll play them both at once so that they're talking over each other. Actually, I can do that, but anyway, uh, we'll, we'll do that. But at first, Fred, um, some very, very sad news, and that is the death of Apollo 11 astronauts, Michael Collins. I heard the news this morning that he'd passed away at the age of 90, after a battle with cancer and look.
Yeah, he was part of the reason I got so interested in space and astronomy and space travel. Uh, I was inspired to go to NASA wouldn't, you know, as soon as I saw Apollo 11, I always thought I'm going to go [00:03:00] there and see this place and learn more about it. And, um, I think my, my favorite moment was going to the Saturn five display at NASA in, in Florida.
And seeing that set in five rocket hanging from the ceiling and it's various stages, it was mind blowing and, you know, uh, Michael Collins was a part of the reason that that happened because, and it's probably part of the reason this podcast is happening because he, um, He was just one of those, those people that was etched into my mind from a very young age, I saw, I saw the Apollo mission at the age of seven.
I think you were probably 47 57. Yeah. And, and, you know, he, uh, he was a follower of the space and that's podcast. I don't know if you, or many people know that I didn't make a big deal of it, but, um, he, he liked, uh, some of our episodes over the last couple of years. Seriously thought that was yes. Yes. I was stunned and [00:04:00] amazed that he paid us any attention at all.
So you know what a great bloke yeah. What a great bloke and, you know, it's a, it's sad, but he lived a long and happy life. And if I could, I'll just read a statement from his family. They say we regret to share that our beloved father and grandfather passed away today after a Valiant battle with cancer, he spent his final days peacefully with his family.
By his side. Mike always faced the challenges of life with grace and humility and faced. This is final challenge in the same way we will miss him terribly yet. We also know how lucky Mike felt to have lived the life he did. We will honor his wish for us to celebrate not more than that life. Please join us in fondly and joyfully remembering that his sharp wit his quiet sense of purpose and his wise perspective gain both from looking back at earth.
From the vantage of space and gazing across the calm waters from the deck of his fishing boat. That's a statement from his family and I think that's lovely. And I think [00:05:00] it's a, uh, a perfect way to see him out from his mortal coil. And, uh, I never got to meet him. I did meet buzz Aldrin, uh, and buzz of course, the last of the trio that, um, that went to the moon and, uh, uh, you know, that, uh, that most famous journey of Apollo 11.
Yeah. What a great bloke. Yeah, indeed. And, um, Uh, just a footnote to that. I was listening this morning to a recording of him. He was giving us a bit of a speech two years ago. So it would have been 88. And you would have thought it was a man 40 years younger. He was firing on all cylinders. Uh, very, very, uh, you know, very calm and, um, it was just the same voice that he had when he was in the, in the command module of Apollo 11, quite remarkable.
Well, one of my favorite stories about Michael Collins, and this is just a bit of trivia that not too many people would be aware of. Although I think I have mentioned it once during. Uh, [00:06:00] time during this podcast, he took a photograph from the module as he orbited the moon while, um, the alarm strong and it would all would alter and were on the surface and the photo consisted of the moon in the foreground and the earth in the background.
And at that time, It was the only photograph in history where he was the only human being, not in the photo. And you know, that's a pretty ex that's pretty extraordinary. When you think about it, he, the photo of everybody else that existed in the world at the time. Yes. Except for him. That, that amazed me.
It's I mean, it's it, it's a piece of trivia, but it is pretty special. Yeah. Mm. Okay. Uh, we will long remember him. Of course. Let us move on to our questions. We've got two questions. I might just play them back to back and then we can answer them both together because they both kind of walk the same path in very different ways.
[00:07:00] Uh, these are questions from Cassandra. And Ryan, so let's see what they, what they're quizzing us about. So my name's Cassandra and I am from Tennessee to in the United States, if you're not familiar with the States. And I just have a really simple and weird question for y'all before I ask you all, I do want to.
Put forth that I am a social studies teacher. So science is not my forte, but I do love learning about space. I'm very interested in space and I love hearing how you guys take advanced space terms and make them accessible to everyone. So my question was originally put forth by my boyfriend, who is a major space night.
And he's always asking questions that make my brain want to explode. That's what I love about him, but he always asked me if there was a car in space, traveling at the speed of light. So assuming a car could survive in space and travel at the speed of light and it turned on its [00:08:00] headlights. Would you be able to see the headlights.
Let me know what y'all think about that. That is a really good question. I've heard that before. And, uh, Cassandra, there is such a car. It's a Tesla, but before we answer the question, we'll go to Ryan because he asks something not dissimilar. Good idea. Guys. Loved your show. Ryan here from Australia. I just want to ask a simple question.
If there is such a thing, if you had to very fast rocket shift end to end in the vacuum of space and they both exhilarated away from each other at the speed of light, but the passengers will stripped in of course, looking back, would they be seeing twice the speed of light? I know it's a crazy question, but I've often thought about it.
So. Yeah. Interesting. Cheers. [00:09:00] Thank you, Ryan. And thank you, Cassandra. And yeah. Speed of light questions are always intriguing and I don't know which way you want to go first, but let's sort of go, okay. A car in space, traveling at the speed of light. You turn the lights on what's going on. What happens? So the, the thing that connects these two questions, Andrew, uh, and they they're great questions.
And they're the sort of thing that people do think about, um, what connects them is that you're adding velocities. Um, your, so with the car headlights, uh, the cars going at. It can't travel at the speed of light because only light can do that, but it can be very, very near the speed of light because we do that with subatomic particles.
So it's traveling almost at the speed of light turns on its headlights, that the light from the headlights is traveling at the speed of light. So you think. Ah, okay. That to a stationary observer, the headlight, the beam from the headlights must be traveling almost twice. The [00:10:00] speed of light and, and the Ryan's question is the opposite.
If you've got two things going away from each other, Uh, what is there the speed at which they're separating? Uh, is it twice the speed of light? If these two rockets are going at almost the speed of light and the answer is no. And that's because when you, when you get into relativity and relativity, Tells us all kinds of very strange things.
Philosophies speeds. Don't just add the way we do in the normal world. Um, I'm very reluctant to put formula into this podcast, but it is actually a relatively simple one. So I'm going to throw it. You're pushing, you're pushing the limits of adequacy Fred. Well, well, I can, I can do it without it. I mean, basically.
Yeah. The answer is always less than the speed of light. That's what happened. Right. So to have a look all right, to, to, um, rockets [00:11:00] approaching each other. Uh, you, you expect their closing speed to be twice the speed of light, if they're, if they're approaching each other, but, and that works in the world where they're not going anywhere near the speed of light, uh, you know, that normal cars, but when you get to these very high speeds, relativity becomes more and more dominant.
And what happens is the addition is not just a simple addition. It's not just one velocity plus the other. It's actually one velocity plus the other divided by one. Plus the two velocity is multiplied together, divided by the speed of light. I just quit it. That's the formula. Don't worry a headache. Yeah.
But what it tells you is that, you know, supposing they're both traveling together. Uh, uh, closing at 0.9 of the speed of light. If they're coming toward each other, it's works the same, that the other direction, um, their closing speed is actually each one's going at 0.9. The speed of light they're approaching.
You'd expect it to be [00:12:00] 1.8 times the speed of light they're closing speed, but it's not is 0.9, nine times the speed of light it's much closer. Um, If people are interested in this and interested to see the formula, there are one or two sites on the interweb, just check out a relativistic velocity edition and it will tell you all you want to know probably more besides, Oh, is it a lot of remember that?
Yeah. A lot of it goes in to reference frames and things like that that we don't want to worry about, but it, it, the bottom line is that. Velocities don't add in the normal way. And there's a practical demonstration of this. We know it happens. We know it works because as you well know, the two beams of the large Hadron Collider, which has spinning round between France and Switzerland in opposite directions at very nearly the speed of light.
I think it's 0.9, nine, nine, nine, 5% of the speed of a times, the speed of light. So they're effectively traveling the speed of light. They collide them. And the collision speeds are that. [00:13:00] You know, uh, an increased fraction of the speed of light, but it doesn't exceed it. So, yeah, it does. Yeah. Uh, yeah. So what you're actually saying is that we should change the speed limits of cars to near the speed of light and will be much safer.
Yeah. Well, that's right, because you can never go. It's like, you know, the speed limiter on a truck. Uh it's but it works in physics. You got exceeds. Yeah. Wow. All right. Uh, it's it's a question I've heard many times and, and one that. That puzzles people. And yes, you'd think if you, if you're traveling near the speed of light and you turn the lights on, that must do something, but it doesn't do anything.
So the answer is, yes, you'd see the headlights, uh, you know, it actually depends on where you work clearly feel behind it. You wouldn't. Uh, but, um, um, the, you know, for an observer, a stationary observer, if I can put it that way, you'd see the headlights cause the two [00:14:00] at the speed of light. And, and if we were driving towards each other at a hundred kilometers an hour, each.
At closing spear to be 200 or going apart, same effect, but at the speed of light or near speed of light, that's canceled out. It's just the case. Will it reach the limit? It gets progressively slower. As you get near the closing velocity gets progressively. It just gets nearer and nearer to the speed of light as the two individual things approach it, but it never exceeded.
There you go, Cassandra and Ron, uh, you have your aunt's on Cassandra. Good luck. Explaining that to your boyfriend. What a way to start a Thursday morning, Andrew with yesterday. Relativistic. Sorry about that. No, that's okay. Uh, let's move on to our next question. And this one comes from Graham. Hello, Andrew and Fred.
My name is Ms. Graham Murray and I'm calling from solvent by the sea up on the Northeast coast of Yorkshire. England [00:15:00] Saltburn is only 10 miles from Martin where captain cook was born and a little over seven miles from States, from where captain cook sailed on his voyage that discovered Australia. So in this part of the world, we're very proud of our historic attachment to ours.
And like many, I have family and friends on both coasts down there. Please. Could I ask you to talk about the mood and specifically the phenomenon of tidal friction? What is the link between water on the earth and lunar friction, and why only water and not say magma beneath the crust, I'm finding online explanations, difficult to comprehend.
So I'm wondering if your tried and tested communication skills will make this easier for me. I believe on one of the Apollo missions, a parabolic dish was placed on the lunar surface. And that lasers on earth can be fired at it reflected back, enabling precise measurement of the distance between the spheres.
This has proven that the moon is gradually becoming ever more distant from us. Apparently back in the age of the dinosaurs, the moon would have appeared considerably larger in the sky. Most of the belief, rightly or wrongly that the presence of the moon stabilizes the Earth's rotation. If this is correct, what are the [00:16:00] implications?
If the moon is becoming increasingly distant, Since discovering space notes, I'm working through the back catalog of everything you're doing and never miss any output, whether on podcast or YouTube. Thanks guys. If you can help explain it all. Wonderful. Thank you, Graham. And, uh, based on your question, Fred is now going to write his next book in 75 volumes, two ads to answer everything you've asked before we get to, um, Graham mentioned captain cook, who came from that, that particular part of the world.
And, uh, yesterday actually was the anniversary. The 28th of April of his. Um, setting foot in what he named botany Bay and botany Bay is in Sydney Harbor. They tried Sydney Harbor. And when you, and, um, or was it the other way around captain Phillips was the other way around? Yeah. Captain Phillip went into botany Bay after it was discovered by captain cook.
And when you. And then went back out and went into Sydney Harbor and went, Oh, this is nice. We'll stay here. [00:17:00] Uh, what nor, uh, but captain cook, uh, yeah, the anniversary yesterday or his, uh, uh, discovery and setting foot in botany Bay. He originally named it stingray Bay for obvious reasons because it was full of stingrays.
But after Joseph Banks went for a wander and went, Oh, what's all this then. Um, which is exactly how he sounds. Uh, he, um, he brought back all these, um, botanical. Uh, bits and pieces and they went, wow, this is pretty cool. We'll call it botany Bay. So cause they found all those amazing plants, including one that's called the Banksia named after Joseph Banks.
Of course. So just a little bit of a connection between what, uh, where grime is from and why we are here in Australia at the moment. Learn friction. There's more to it than that we say, well, there's a connection. Um, I know that area very well. Oh, of course. Oh yeah. Yeah. I was going to mention that too, but I totally forgot, but, but there is another point that, um, we're [00:18:00] always at pains to make here in Australia and forgive me, Graham for mentioning this, but captain cook.
Uh, did not discover Australia. A lot of people knew about it already, and wasn't going to split hairs. No, it's not splitting hairs. Really. If you're one of the indigenous people who lived, you know, whose ancestors have been here for tens of thousands of years. So it's a matter of, uh, I suppose, um, Uh, communities coming together rather than discovery, something like that.
We really do want to split hairs, which I'm going to do now. Uh, the first Europeans to discover Australia were actually, was it, uh, uh, the Portuguese or the Dutch? Because the Dutch, yeah, it was the Dutch. Yes. I thought so my wife she's Dutch. Yes. But yes. Um, Yeah. Yeah. A lot of people found it. And in fact, and in fact, here's another piece of trivia, uh, when, when the first fleet arrived, we'll get there.
Eventually when the first fleet arrived in 1788, there [00:19:00] were two French war ships off the coast. Yes. There you go. We're here going, this is Alice who leave. Terrible French accent. I think it turned into Spanish somewhere along the way. They might've been here too. Um, yeah, lunar friction. So I forgotten the question.
No, I haven't. It's okay. Um, look at growing that the main thing is, uh, and you kind of put your finger on it, uh, in your question, why only water? Well, and why not say Magnum a bit beneath the across and it is it's everything. The tides actually, uh, pull everything around. So the surface of the earth moves twice a day by something like a foot on average, uh, D varies from place to place.
Uh, so it's not just the tide's going up and down. We are going up. That's why I miss those crucial parts. It's the movement. It's tidal friction. That's what it is. That's right. That the ground is [00:20:00] changing under your feet. Fortunately, it's slow enough that we don't get earthquakes, but, but that's an, and that's what is also happening on the moon.
And that's really the connection. That's where title friction comes from, uh, because, um, as the tides raised on the moon by the earth shift, the moon surface by a small amount. Basically that's causing a loss of energy is that's what stripping the energy from this rotation. Uh, the, that, uh, that's why we need leap seconds because the earth is gradually very gradually slowing down.
It's about one millisecond, maybe a little bit more than that. Per day per century. So it's a very slow effect, but if you don't do anything about it with atomic clocks, everything gets out of kilter. And before you know where you are, you're celebrating, uh, equinoxes and salts disease in completely the wrong times of year.
So, uh, that's the slowdown and it it's actually, um, uh, the, uh, the same effect, the same [00:21:00] phenomenon. That is giving rise to this gradual drift of the moon away from the, uh, away from the surface. And actually, uh, those reflectors that you mentioned, Graham, they are what are called corner cube reflectors. And I think the first three missions may be more than that, placed them on the lunar surface.
It wasn't just one of the Apollo missions. These are banks of reflectors a lot, like the old cat size. We used to have 'em in the middle of the road. Uh, and what they do is send beams of light exactly back from the direction in which they came. Uh, so they've got 180 degree reversal of the direction, and that means if you shine a laser towards them, you get your laser beam coming back and, um, modern technology lets your time.
The flight of the laser beam, which is why we know the distance to the moon with an accuracy of about one centimeter. It's extraordinary, totally extraordinary. And that's how we know that. I think it's 3.5, four centimeters per year is the drift away from the earth [00:22:00] by the moon, which all, um, Leads to eventually the, to stabilizing the, uh, absolutely.
You know, the end product of all this is that the moon will wind up about a half, a million kilometers away from the earth, rather than it's 380 kilometer thousand kilometers that it is now. And the two. Uh, worlds will always face one another, just as the moon faces the earth with the same face all the time, the same will be true of the earth.
This is in maybe 10, maybe 20, maybe 40 billion years. It's a long, a long way away. And actually other things will happen before that. But that's nevermind. Um, there was one of the things that I've set an alarm on my watch. Very good. Well, you might want to do one for the collision of the Andromeda galaxy without turning into a red, giant covered, already covered.
Good. Okay. Um, so yes, the, that that's proves the moon. We know the moon is drifting away and exactly, as you said, in the age of the dinosaurs, it was a bit bigger, not [00:23:00] 66 million years ago. Um, So, uh, the, uh, final, uh, let me just digress for a minute to explain why the moon is moving away by the same process.
And what happens is that, um, it comes about because the earth rotation is in the same direction as the moon's orbit. And these things, all, they're all everything's going anticlockwise from above the Northern North pole seems from above the North pole. So the earth rotating and that carries what we call the tidal bulge around with it.
Um, and that's the, the bulge in the oceans and the crust of the earth, uh, that's caused by the moon's gravity. So that's slightly offset from the direction of the moon. And what that does is it gives the moon itself. A slight gravitational tug, which increases its Philocity slightly. And if you increase the velocity of a spacecraft, what happens is you move away from the object here and always around.
And that's why the [00:24:00] moons drifting off. Okay. The final bit is, uh, Yes, they, um, that we do believe that the fact that the moon is there is one of the things that stabilize the Earth's rotation. And that will continue. I think even when the, to reach their equilibrium point in all these billions of years, where each is facing the other, the moon will still be there.
It's not going to vanish all together. It will not be big enough to cause total eclipses of the sun. However, it will be significantly smaller in the sky than it appears now, which is a rather curious phenomenon. The fact that yes, it's just. Coincidental that we can observe it. Exactly. Yeah. It's lovely.
It's a lovely effect too. And we get to witness it here in 2028 and there's going to be a full eclipse, uh, which we'll see a shadow run right across the note from the Northwest of new South Wales, straight over us, where I am now total blackout and, uh, Sydney Sydney will get blacked out as well in 2028.
Mm, great. Um, thanks for your question. Uh, great one. Uh, [00:25:00] and you are listening to. Episode 250 of the space, nuts podcast space nuts. This is space nuts. Andrew Dunkley here with professor Fred Watson and a big hello to our patrons. The people who have been supporting us with a couple of dollars a month to keep the vessel afloat, the HMS.
Endeavor as we try that, that was captain cook. She cooks shit by the way, uh, as we try to, um, pass on valuable information in a language that you can understand. Adequately, uh, but to, uh, patrons, thank you. Uh, whatever way you support us financially, it's, it's certainly appreciated. And if you want to go to patrion.com/space and that's, you can see how it's all done or go to our website, a website, spacing out to podcast.com and clip up, click on the subscribe button to find out how.
You can, uh, assist us where we're aiming to become 100% supported by our patrons. And of course we [00:26:00] need to get the numbers up. So if you would like to become a patron, it's not expensive, uh, and you can choose your poison basically. Uh, but as I've said many, many times, it's not mandatory. So please don't think we are going to make you do this.
That's not how it works. It's a volunteer thing, but to those many, uh, who have already done, so it's greatly appreciated. So for it, let's move on to our next question. This comes from Patty and Alyssa. Could I? Fred and Andrea Patty here again, my daughter is here with me, um, and she asks about rainbows through glass because each time we get home from work or I get home from work, Alyssa always points out the rainbow on the driveway.
And I said to her, it's a light spectrum, I think, um, dividing the light to different colors. So the rainbow, and then she says, no, it's not, it's, there's a leprechaun. We have to find the leprechaun at the end of the [00:27:00] rainbow. And this is gold. And I'm like, okay, rodeo. So what makes a rainbow? And can you explain it to my daughter, Alyssa?
Thank you and may the force be with you. Thanks, bye. Thank you, Patty. And hello, Alyssa. And, um, all on your side in regard to the leprechaun and the pot of gold. I do believe it. And, uh, I haven't found it yet because. You can't get to a rainbow because the more you try to get to it, the further away kids, it's just, it's one of those strange, it's one of those things that they just do to us to make us frustrated, I think.
But yeah, we had a recent question, Fred, about rainbows from a, I think it was a bus driver who I noticed at certain times in the day it was coming through the edge of his. His window and creating this incredible effect on the dashboard. And from time to time, you do see might I've seen them with the garden, uh, the, you know, the sprinkler system in the garden sometimes it's, um, it's a lovely effect, [00:28:00] but, um, yeah.
Uh, I guess we can educate a litter a bit in terms of what's going on, but you cannot just sit there and look pretty well. Thank God. One of us can, um, the, um, Well, you know, seeing them in the garden is lovely. And I, this is something I don't tell many people. And, um, you know, it's the kind of thing that you probably shouldn't tell many people, but when I'm in the shower, um, between about, uh, October and March, I can see rainbows in the shower.
Uh, well, just from the shower spray because, um, there's that. Window in our shower faces East. Uh, and, uh, it's just at certain times, those certain times of the year, the sun is, uh, high enough in the sky. We're in the right position in the sky to, to shine on the, on the part of the, you know, the droplets of water coming from the shower and they make a rainbow.
You've got to look hard for it though. But it is there. Yeah. And that's telling you [00:29:00] exactly how rainbows are formed. Um, it's billions of raindrops, uh, and the sunlight passing through them actually is split up into the colors of the rainbow, the spectrum exactly as Paddy says, uh, and, uh, reflected back to us.
It's really interesting what's happening in East, uh, in each raindrop, Andrew is that, um, the light is going into the raindrop, uh, It's being refracted. That means bent by the surface front surface of the raindrop. Then it reflects off the back surface of the rain drop comes out of more or less the same side that it went in, uh, but at a slightly different angle.
And the end result of that is that the, the light is bent actually through an angle of 138 degrees, which means. That if you are standing with the sun behind you, uh, what you're seeing is light that's actually coming from a donor angle of 40 to 42 [00:30:00] degrees. To the, um, basically to the, the direction of the sun where the sun would be.
Um, I'm getting, you know, I'm not putting this well at all. It's what, technically all the anti-solar the anti-solar point is the point directly opposite the sun. And it's 42 degrees to the anti-solar point. So what you get is this arc of light centered. On the anti-solar point, the point directly opposite the sun and it's caused by all these gazillions of raindrops bending light through this 138 degree angle and splitting them into the colors, uh, a very, very complex, uh, account.
But the bottom line is exactly, as you've said, In a sense, a rainbow is an optical illusion because as you move the rainbow moves with you, you know, if you went to towards one end of the rainbow to dig up the pot of gold, and we used to believe there was a pot of gold at the end of it as well. Um, I did the digging involved.
[00:31:00] Yeah. Oh, you've got to date manual labor should not be required in Yorkshire. You had to dig for everything. It didn't matter what it was yet to do something. I buy gum. You couldn't just go there and pick it up, you know? Um, so, uh, the, the, um, the, the rainbow, you know, Okay. You had had towards the end of it where you think the pot of gold is, and the rainbow just goes with you because it's this kind of optical illusion.
It's always at this 42 degree arc in the sky. They're delightful things. Honestly, I think rainbows are completely magical. Uh, and I look out for them whenever I can see them, especially in the shower. I'm going to ask a question of you in addition to what Patty and Alyssa have brought up, uh, the good are rainbows, unique to earth, or could they exist on other planets?
And here's another sort of side question to that question. Let's say you're on a planet. Where it's raining and it's a blue, giant star [00:32:00] rather than the color of our star. Would the rainbow be different? Yeah. Um, and look, you've hit a point that I, you know, the kid's book that I've been working on. Um, the, uh, it's gone, it's going through the editing at the moment and I had a little feature on alien rainbows.
Exactly what you're asking about. And, uh, yeah, except that the publisher says women got room for this should cut it out. So it's going, I'm afraid. Um, I might try and sneak it. I mentioned in somewhere else, because it is a lovely topic. Um, I might actually, in fact, I it's how to do it and I'll change it and make it shorter rather than make it, uh, um, uh, you know, as long a feature as it was.
But the answer is yes, Andrew and one place where. Even in the solar system, there might be rainbows, um, is, is Titan, uh, Saturn's moons tightened because Titan has a water cycle [00:33:00] similar to the earth, except it's not water. It's hydrocarbons, it's liquid, natural gas. Um, but they're, uh, probably, uh, we expect while we know, because we see clouds, uh, we believe that we would, you would see clouds of droplets, of liquid methane ethane, which is what it is.
In the atmosphere and that, um, would give you rainbows. Uh, there wouldn't be as colorful as here on earth, because as you know, tightness covered with this smoky atmosphere, uh, which is it like an orange fog? So a lot of blue light will be taken out. So your rainbow would look. Predominantly orange basically.
Uh, and it's a different angle as well. If I remember rightly it's 48 degrees, the, the radius of a methane rainbow rather than the 42 degrees, the radius of a water rainbow. So yeah, that'll happen. Uh, one of my colleagues just as a final footnote to this, uh, um, one of my colleagues from [00:34:00] the university of new South Wales.
Uh, it's uh, and th the group that he leads, uh, there, Jeremy is his name. He's a very senior, extremely expert. Astrobiologists he and his colleagues are looking for the signature of rainbows on other planets, beyond the solar system. And you do it by looking for the polarization of the light, rather than, uh, you know, rather than, um, looking, looking for the arc of light.
If you see. Cause Paul, uh, rainbows, highly polarized. Uh, if you look at a rainbow here on earth, through polarizing sunglasses, turn your head around. You'll find an angle where it disappears altogether because the lights out. Right, right. Try that. Speaking of books, Fred. Yes, my brother, my clever brother has come up with this.
I don't know if you can see it. Oh, that's the one. That's the color. That's the right place. That's the cover of my new book. Yep. Yep. He's done a great job. [00:35:00] Um, and that'll be out next year. I've just decided to fast track it and get it out there because you know, why wait. Yep. And I don't have to go through all the rigmarole of editing and convincing publishers are shouldn't, shouldn't put certain photos in the book, just do it myself.
Um, but, uh, thanks again to Patty and Alyssa. Uh, for the rainbows question, let's move on to a question now from Ralph. Hi, Andrew and Dr. Fred Watson. So this is what it feels like to be near a star. We wake up in the morning and stay light and we take it for granted. We walk outside and see sunlight beaming everywhere, the reflecting everywhere, and we feel its warmth on our skin.
But. What this really is, is energy rocketing at us from our nearby star. We're exposed to it directly for half of our rotation and are shielded from it during the other half. So this is what it feels like to exist near star. We look out in the night sky and see billions of other stars, but we're told the universe is mostly space and emptiness are only experiences.
What it feels like [00:36:00] to be in the neighborhood of a star. So what's it like to be out in the middle of nowhere? Not anywhere near any stars. Is it simply cold and dark and nothingness, or are there faint wisps of energy from nearby galaxies? Or dark energy effecting that space or gravity. Is there anything we take our existence here for granted so much?
I'm just wondering what the opposite would be like. Not in the neighborhood of a star, keep it up. Chief nuts. Love the podcast as always. This is Ralph and Northern California. And thank you. No worries. Well, thank you very much. Um, there'll be no rainbows. I don't imagine. Unless you created one yourself, you can get to be pretty cold and dark and uh, it'll be, um, Yeah, pretty boring, too.
Interesting. And I do have the answer and actually you upstage me a bit there because what I was going to do was. Put this up in front of the camera, exploring stars and invisible planets. Exploding stars. Yeah. You shouldn't have, um, [00:37:00] what's called cosmic Chronicles here in Australia and the reason I've, uh, I grabbed it before we started, because I knew this question was coming up is because that is exactly how the book starts.
It starts with a typical place in space. And I'm going to, since I've done it already, I'm going to read the beginning of the book. Right. In fact, I might read the first two paragraphs, if that's all right, this is fine. This is going to be interesting. Cause Fred has to read his own writing. Uh, yes, indeed.
Okay. Suppose you, you could come with me to a place that is typical of the universe, a location that experiences, the average conditions found throughout the whole of space. Where would we be on the surface of an alien planet, perhaps luxuriating among exotic plants and strange colorful creatures or close to the brilliant churning atmosphere of a hot star with torturous magnetic fields, funneling lethal bursts of plasma to orders.
Oh, what writing? [00:38:00] Falling into a black hole perhaps, or just. Nowhere. And it's the last of these that is closest to the truth. A typical place in the universe is empty, cold and dark, and nothing in our experience can quantify just how empty, cold, and dark it is. If you're lucky, you might find one atom of hydrogen in the volume of space, normally taken up by 15 adults, a cubic meter.
The temperature you'd experience is 2.7 degrees above absolute zero or minus 270 degrees Celsius. That is cold until you're an 80 dies. That darkness is complete, but don't worry. I'm not going to leave you here. And you've got to read the rest of the book to find out what. Well, everything else is light.
So it is typical universe place in the universe. There's essentially nothing. There's the old hydrogen atom. There's [00:39:00] probably dark matter though, which we can't experience, um, you know, in any other way than through its. Gravitational attraction when it gets to large numbers, but we know dark matter, outweighs normal matter by five to one.
So that means you might find five atoms of dark matter, whatever it is in that one cubic meter of space, the average space between the, between the galaxies extremes. Yeah. Yeah, it is. Ralph's opened a can of worms, but it's okay. There's nothing in it. That's
a great question there really good question. And, uh, I kind of figured that's where we'd, we'd go with that one. Um, a typical, typical piece of the universe is, is basically nothing. Um, Yeah. Yeah, no, it's kind of like my scorecard after a round of golf, nothing, nothing to write home about. Uh, thank you, Ralph.
Appreciate it. And, uh, we will take a little break and come back with our [00:40:00] last two questions on this episode, 250 of the space nuts podcast. Okay.
Thanks for joining us and hope you're enjoying this, the latest episode of space and that's episode 250. Now I mentioned earlier that we're trying to build up our patron numbers to try and self-support the podcast. And that's great if you can do that, but if you want to support us in another way, go to our website, spacing that's podcast.com.
Click on the shop. Blink and maybe buy yourself a t-shirt or a polo shirt or a cap or a cup or, or a mug. I don't know what the difference is between the cup and the mug. They look the same to me, but anyway, there they are. Uh, but there's a little tab on the lift. This is sort of following on from something Fred just showed you.
If you're watching on YouTube. It's got books and they're all in there. Uh, all sorts of books, uh, that, um, have been, uh, put in there. There's a stark raving mad by [00:41:00] Fred Watson. There's exploding stars in invisible planets by Fred Watson, uh, and, uh, a couple of other books. That, uh, by some, uh, virtually unknown author, uh, who shall remain nameless, but, uh, they're all there.
Uh, or you can just check out our catalog as well. It's all on space and that's podcast.com uh, click on the shop link to see what's what we can even sell you. A couple of stickers. They're cheap as chips. So check it all out. You can support us that way. If you sort of don't want to go as far as becoming a patron.
So that's an option as well. Now Fred, uh, two more questions to bump off before we call it quits on this episode. And we, I love this question mainly because I am currently watching this TV series. This is a question from Andrew. Hey guys, this is Andrew in Victoria, BC. Um, I have a question about, uh, the TV show for all mankind.
Um, specifically season two, episode one, um, [00:42:00] There is a part of that episode where a coronal, mass ejection occurs and the astronauts on the moon have to basically run to safety. Um, a lot of them get underground, uh, or in lava tubes. Um, but you do notice a part where the regulator or the sand on the movement is actually elevating from the surface kind of in waves, like fashion.
Um, it was quite a sight. I'm just wondering if that's. Scientifically accurate. And if that's something that would typically occur during a coronal mass ejection, uh, I love the show and thanks for your time. Thank you, Andrew. And hope all is well in British Columbia. I watched this series, Fred, I've been, uh, I was put on to it by a friend of mine and I've watched, uh, I think we're in season.
Two or is it certain to-I think it's season two. Uh, and it's based on the premise [00:43:00] that it's one of those alternative history series. They made one, uh, where the Germans and Japanese had won the war. That was a great series. I've watched all of that. Uh, this one's based on the premise that the Russians get to the moon first.
They, uh, the first to set foot on the moon, it freaks the Americans out and the space race changes. So the Americans think, okay, well, they step there first, but we'll put the first base on the moon. The Russians have got the same idea and they put a base on the moon and then they start thinking, well, we need resources.
So they start mining the moon. But the Russians say, well, We're going to do that too. So we'll take your mind and then they have to fight to get their mind back. And it's really fascinating. I think at the current stage they're in, into the eighties, Ronald Reagan is president. Uh, the Americans got a base on the moon and yes, in this particular episode to start off the latest season, They detect the coronal mass ejection, which is headed straight for the S uh, the surface of the moon, [00:44:00] where the base is and where the Russians are for that matter.
And the, um, the astronauts are all exposed about, uh, 11 of them, I think, uh, on the surface, in their suits, they were actually going to watch the sunrise. Uh, because it was so spectacular and the coronal mass ejection was minutes away and they had to find cover now as a part of the effect, when the coronal mass ejection hits the surface, the lunar regolith, the surface of the moon ripples, like, um, like when you vibrate a dish that has got water in it and you get that ripple effect, that's what happened.
And Andrew is of course wondering, uh, if that would be real. Now as a journalist, I never let the truth get in the way of good story. More as a science fiction writer anyway. But, um, yeah, I wondered the same thing. Uh, I th yeah, it's I haven't seen the series. I haven't seen the episode, but it's fabulous. Uh, yeah, [00:45:00] we were speaking about it earlier and it's very tempting if ever I get time to watch TV, I'll watch it.
Um, the, um, and the answer is that it is probably based on fact because the. Lunar regolith. The lunar soil is, is very, very fine. It's fine. Other than talcum powder, um, um, it reacts to electrical charges. Uh, and so we know that from observations made by a, I think it was Apollo 17. There's a very famous sketch.
Of looking at the limb of the moon, the edge of the moon from orbits. This is from all this around. So it's from the command module. You can find it on. It's probably on Wikipedia. I think th th th the sketch shows the, um, the, the, the, the limb of the moon, the horizon of the moon just before the sun comes up.
So the sun is illuminating [00:46:00] from just below the horizon and all these. Clouds of material of visible. There are, there are there's, there's a sort of haze around it. Now the sun, the moon does not have an atmosphere, so it's not an atmospheric effect. And that led to this understanding of something called the levitation of the lunar regolith.
And I think that there's probably a Wikipedia article on that as well. So levitation of the lunar regolith means that. Just under the normal solar wind that, you know, the, the, the normal effect of the subatomic particles coming from the sun, it charges up that lunar soil so that the particles of soil repel, each other, they become charged like charges repel, uh, and essentially float above the, above the surface.
It was not visible to the. Astronauts on the moon, standing on the moon, they couldn't see this effect happening, but when you see it from space where there's probably a large clouds of this [00:47:00] dust being back illuminated by the sun, then it became visible. So it's a, it's a really good suggestion that if you have.
A really intense, uh, dumping of charged particles onto the moon surface from a Corona coronal mass ejection on the sun, that plasma basically being burst out of the, uh, of the sun's photosphere, the surface that we see, um, you, you might well get an effect like that. I'd, I'd love to see the special effect.
I'll try and look it out. Actually. It's a really good time. Yeah, really? What they can do these days is stunning. Yeah. Uh, but, um, but it, it, it could be possible. Um, uh, maybe one day we'll find out with cameras on the moon. I've actually found the photo you're referring to. I just did a Google search for levitation of the lunar regolith, and then clicked on, clicked on images.
And there are quite a few photos. The effect or demonstrating the effect. So yes, you can find it quite [00:48:00] easily. Good. But yeah, if you, if you are interested in that series, it's on Apple TV and yeah, there's been, I'm pretty sure it's, I'm not sure if it's Susan two, a season three, but it's so good. Yeah. I'm way behind.
I've got some catching up to do, but, uh, it's a, it's a really well thought out and clever alternative history storyline that. Uh, just keeps you wondering where they're going with this. How can this, how is this going to end? And, uh, I suppose if I want to just be a real nitpicker, uh, sorry. Some of the movements that they've tried to replicate of the astronauts on the surface are a little bit iffy, but especially when they're walking around inside their, um, uh, their quarters, they suddenly look like they're in their own bedrooms because they seem to be moving quite normally, but they're not in space suits.
So. I guess you'd have to wonder, well, maybe that's how it can help. Maybe that's how they do walk on the moon. Um, [00:49:00] they seem to be being, have become much more sure. Footed compared to the Apollo astronauts as well. Cause they fell over at it right or not. But, uh, yeah. Uh, great question, Andrew, and, and probably some fact to it of some kind.
Yes, indeed. Uh, okay. Let's move on to our final question for this episode, 250. Have I told you it's episode 250 it's 250, just in case you're wondering, uh, this is a question, uh, from another part of Canada, Andrew and Fred. My name is Mark. I'm a recording from the, uh, city of Sherbrooke in the province of Quebec in Canada.
Now, um, if we want to send a mission to Mars, we have to wait for the correct launch window because of the orbit of the planets right now, does this same logic apply? If or when we want to send a probe towards Proxima Centura? Or can we just aim for the shiny little dirt and just go straight ahead. [00:50:00] Uh, I love the bus gas and please base nets around the globe.
Please support the show if you can. Thank you. Thank you, Mark. Thank you very much for the boost as well. Uh, I would think. When you're going long haul, it wouldn't matter, but I'm willing to be corrected on that. Cause I don't know anything. Um, no, you're absolutely right, Andrew. Uh, the dis you know, the, the reason why we need, we have these launch windows with Mars is to give us the minimum energy transfer time between the earth and Mars.
Um, if you had. Uh, if, if you, if you had rockets that, you know, if you hadn't basically could put whatever thrust you want, rather than realistic considerations of fuel and, uh, things of that sort, if you could just zap your rocket up to any speed you want the, the launch windows broadened there, they get much wider.
Um, and in a way, when you're thinking about Proxima, Centauri, I mean, [00:51:00] You know, sending a conventional rocket to Proxima Centauri is a non-starter because it takes you 60,000 years to get there because it's so fun. Yeah. Um, and the price go up too much, would the only practical way to think about it is that, you know, what, what they're looking at with break.
The what's it called? Breakthrough star shot the, um, um, feasibility study for whether you could, uh, use a light, sail to accelerate a spacecraft to nearly the speed of light and do it in a lot less time. Um, but even then you're talking about a journey time. Okay. So it's, if you were accelerating up to a third of the speed of light or something like that, you're talking about maybe 13, 14, 15 years.
Travel time to take into account the accelerations and things. Um, that is a long enough period of time. Um, that they've probably been several orbits of the planets of Proxima, uh, [00:52:00] in that meantime. And, you know, um, we still don't. W we can't actually see these planets directly. So we don't know whereabouts they are in their orbits.
We've just got the times that they, um, they transit or that they pass in front of the front of the star. We can tell from the, the wobble of the star, whereabouts, roughly whereabouts they are. Um, I guess what you'd be talking about. Uh, just, you know, suppose yes, there is a spacecraft on its way. There you do what they do with long haul flights within the solar system, you make mid, mid cruise, uh, ma mid cruise maneuvers.
You, you basically tweak the orbit that you're in. Um, by doing course corrections. And th and you do that as you were approaching, uh, approximate, so that you brought yourself in the best position to have your cameras photographing. The planet says you always buy them because there's no chance whatsoever slowing down to go into orbit.
It's a bit like [00:53:00] when Erica. Which we used to call ultimate Thula or ultimate tool, a, uh, that objects, a photograph by new horizons, the new horizons or a bit, um, it's pathway its trajectory in space was tweaked in order to bring it within photographing range of Eric auth. Um, so in the, what was it phase 2019?
I think so four years after the flyby of Pluto, the obit was tweaked very soon after the flyby Pluto, uh, to bring, um, uh, uh, ultimate tool as it was then called into, into range. So yeah, that's how you do it. So, no, you don't need to worry about windows. You just Chuck it out there and we'll see in 30 years.
That's right. But, uh, yeah. Thanks for your question, Mark. And thanks to everybody who contributed to episode 250, we got a whole swag of questions. So we've got a little bit to work with going forward. Uh, thank you to those people as well. If you didn't [00:54:00] get on this episode, uh, listen in for a future episode when we might get to it.
Then one more thing before we finish up Fred ingenuity flight number three has been successful indeed. And we've seen, uh, images from the, from the helicopter color images. Uh, not only of the tire tracks of perseverance, which is what we saw from flight two, but flight three has revealed the perseverance Rover itself.
Uh, some. 80 meters away or something like that, uh, in the, in the corner of the field of view of the ingenuity camera, so exciting stuff. And in fact, I'm not sure where we are with the status of flight for, um, it may even have happened already. Uh, but we'll follow up on that and make sure I don't think it has, but I think it's due very soon.
Yeah. So I think the plan five test flights, wasn't it. So there's four or five test flights. That's right. And four and five were going to be much more adventurous. So they might still be thinking about where to go. Yeah, I [00:55:00] think with flight number five, they're planning to deliver some pizza. So that that'll be a real issue.
Do that. I thought I thought it was a book pizza. Anyway, actually I read today, speaking of, yeah, drones and helicopters, girl Scouts in the United States, again, because of COVID they can't do the normal door knock to sell cookies or sit out in front of supermarkets. One, lot's going to use drones to deliver cookies.
Okay. Great. That's great. Yeah, that's awesome. Uh, just a side note. Uh, thanks again to everybody who contributed. Thanks for listening into episode 250. Don't forget to tell your friends, follow us on Facebook. Follow us on YouTube. Um, spread the word. If, if you, um, get our notifications on Facebook, please share them to all your friends.
Uh, we want to pick up more and more and more listeners. We want to keep this happy ship flying through space for as long as possible. And Fred, thank you so much. It's been a, it's been a joy as, uh, as always, but, uh, nice to reach a significant milestone as, uh, [00:56:00] as this 250, not many cricketers get to get a score like that.
So I feel rather privileged. I think. That's right as always. Yeah. Yeah, no, I was just going to say, and in case anybody, any of our viewers are wondering whether we coordinate our shirts before we start accordingly, the answer is no, it just happens by accident for folks. Yeah. I even decided to wear a different colored jumper, but we're almost matched in that regard as well.
Extraordinary. Thank you, Andrew. Always good to tell. We need to talk about this. Maybe we do. Yep. Alrighty. See you next time, Fred. All right. See you soon. Fred Watson astronomer at large part of the team here at space nuts. And thanks again for supporting the space. Now it's called podcast and thanks to Hugh back in the studio for putting everything together and we'll join you again next week for another episode of the space and that's podcast.
See you then. Bye-bye
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