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Tickets go on sale to the general public June 30th at somethingworthknowing.com. So come build a better world with us on September 16th and experience something worth knowing you can get your ticket at Complexly.info slash something. Hello and welcome to Dear Hank and John! Or as I prefer to think of it, Dear John and Hank and Dr.
Katie Mack. Hello. It's a podcast where two brothers and sometimes a special guest answer questions give you a few advice and bring you all the weeks news from both Mars and AFC Wimbledon and also talk about the universe together. John, one time at the end of my physics lecture, I went to my professor and I said, I said, what happened before the Big Bang though?
And he said, sorry, there's no time. That's the bad joke. Dr. Mack, is that funny?
Good answer. It's hilarious though. Yes, definitely. So we're joined today by noted Canadian American astrophysicist Dr.
Katie Mack who is the co-host with me of a hit new podcast called Crash Course the Universe that is the history of the entire universe, right Katie? Yes, it's we're doing the whole thing. Oh, yeah, not just we tell the whole story from the first second until the future. Excuse me.
We take like half of episode one to get to second. That's true. There's a lot of picoseconds involved, a phrase I didn't even know before this. But then you also look at like what's gonna happen because we kind of we can draw the line out pretty effectively.
And this podcast was really inspired by my reading of Dr. Mack's incredible book The End of Everything I was for Physically Speaking, which discusses The End of Everything and really got my head going. It's not that discouraging to me personally because I won't be here. But some of my protons will be.
Right? Yeah. Yeah. It's all the same stuff.
It's very weird that like I can lose my air pod, but it's like definitely out there somewhere. Like we know that for sure. It's somewhere. Yeah.
Yeah. If you think that's weird, wait until you hear about how protons sometimes have things that weigh more than protons inside of them, but they still weigh what a proton makes. It's infuriating. Apparently it's just all the protons are just sharing that one big particle amongst them.
That's the only way it makes sense, right? No. No, it's not that. She didn't like that.
I mean, I wouldn't even be surprised if it was that way. Like it just it's such a mess. It's such a mess. That whole quantum.
Oh my gosh. Yeah. I do. Once you get into quantum stuff, it gets really mind-blowing.
And that's one thing that we got to in the podcast just a little bit. We're not trying to like teach graduate level astrophysics here. We're just trying to get regular people like me excited about being in a universe, being part of a universe. Like we're not just looking at it.
We're made out of it. Yeah. Real weird. It's wild.
So anyway, check out the new podcast Crash Course in the universe. I think one episode is on the Dear Hank and John podcast feed. But if you want more than that, you got to subscribe wherever you get your podcast or watch at youtube.com slash Crash Course. If everybody goes about that like right now, then it will like shoot up the charts.
I just want to really know one podcast in America that shooting up the charts. That's a big deal. It matters. So just check it out.
We're just looking to replace Joe Rogan at the top of the hit list. Wouldn't that be a thing? Where are they cause? Yeah.
So where are they cause? I think for the whole universe. Absolutely. We've got some great questions about the universe.
Weird ones, mostly for Dr. Mac, but a little bit for me now that I'm I've asked a lot of questions about the universe. This first one comes from a hana who writes Dear John and Hank, when the universe expands to existing stars and clouds of gas and star nurseries move to take up that space like how gas fills the entire available space or is new matter actively created in that expanded space. What will this new matter be?
Did the Big Bang create all the matter that will ever exist in the universe? Very confused. What is going on? I feel like you can actually answer this one, Katie.
Yeah. This is a great question. You know, there was so the idea that as the universe is expanding, more stuff is being created was was one of the big theories about the universe back in the day early 1900s sort of, well, yeah, some of that in the first half of 1900s. This is the idea of the steady state universe, right?
And it might have been a little later than that. But anyway, there was this idea that the universe is expanding, but like new matter is showing up. So it'll look the same all the time. Like they'll always be the same amount of stuff.
And we now we really don't think that's happening. What it looks like is that everything's getting farther apart and there's just more empty space, right? And so amount of stuff as well. Yeah.
Yeah. Yeah. So so what we see when we look at the expansion, the universe is that things are moving away from us, things are moving away from each other. There's more space in between stuff.
And that to be clear, that's only happening on like really large scales. So between distant galaxies, there's more space happening between, you know, the Earth and the Sun, there is not more space happening. Right. I'm not getting bigger.
I thought that for a second. That like space just gets bigger. But like, how would we know if it was happening if we are also part of space? We just maybe have like maybe humans used to be great.
We're gotten, but no, we are the same size. Yeah. Yeah. All the stuff that's like sort of bound in some way is staying bound in that way.
Right. So like the galaxy is gravitationally bound, the solar system is gravitationally bound, clusters of galaxies are gravitationally bound. Those things stay together. But the sort of more distant things between, you know, more to some things where there's a lot of space in between are just getting farther apart.
And so the density of matter in the universe is going down, the density of radiation in the universe is going down over time. The one thing that the density does not seem to be decreasing is dark energy. And there's, there's a lot of research into this and things are getting messy area. But it appears that dark energy kind of remains at a constant density because it seems to be just something that's tied up in how much space there is.
Like there's a certain amount of space that is certain amount of dark energy or cosmological constant in it. And so if that's the case, if it really is a cosmological constant, that's just a constant of the universe, then the amount of dark energy is not changing. The amount is changing, but the density is not changing. There's more dark energy.
That makes total sense by which I mean, it does not make any sense at all. I was going to say, I mean, it's got to make sense to somebody because to me, dark energy itself, the cosmological constant itself, like puts me at the very edge of where I can understand the idea that there is an energy that's constant that we don't understand and can't observe is a little bit of a minor. I'm going to pretty strong like, this is a current, like we have to have this here for things to make sense. But like, it's just making things make sense right now.
It's just a constant. I mean, what we see is that the universe is expanding. What we see is the expansion of the universe is accelerating. And so we have to call whatever's doing that something, we call it dark energy.
A cosmological constant is a kind of dark energy that we've theorized that is just tied to how much space there is. It's a sort of property of space. And that seems to fit the data for the most part. There are a couple places where we're the luncheon at the moment, but it seems to fit.
And if that's the case, then yeah, there's this weird stuff that's just kind of built into the universe that causes more expansion. And when there's more space, there's more of that. So there's more expansion. That's why the universe is accelerating in its expansion.
But we don't have an explanation for it at any level, like there are theories, but we don't have anything where we can say like, this is what dark energy is. This is why it's like that. It's a huge mystery, really. But so the point of that is that like, yeah, the amount of matter seems to be saying the same, which means the density of matter is going down.
The amount of radiation seems to be basically saying the same, although radiation matter kind of turned into each other in certain ways. The density of that is going down. The density of dark energy is possibly not going down. So there's something that's there's more of it as there's more space, but it's not matter and it's not energy.
Yeah. So does this mean that time is really just things getting further? Oh, boy. I don't know if we needed to bring time into it.
No, but that's an excellent segue to talking about the way that we talk about time as cosmologists. So we in general in cosmology, we don't talk about time in terms of like billions of years. We talk about it in terms of, well, we usually use redshift, which I'll get to that in a minute, but that's side to what's called the scale factor, which is like the size of the universe. So when we talk about seeing a distant galaxy, we're really tying that galaxy to how big the universe was when the light left that galaxy and came to us.
Because we can only see that galaxy as it was however long ago it took the light to trust us. And so you're saying that the like the eight, you're not thinking about time, you're thinking about the size of the universe. You think about time as size. That's like the timeline we use.
Yeah. So what we actually observe is we see the light from that distant galaxy. We see that the light has been stretched out by the expansion of the universe in the time that the light has been traveling to us and the amount that that light has been stretched out is called the redshift. And we sort of order things in time by redshift rather than by time because we can observe the redshift directly.
We see exactly how much that light stretched out, but we can't we've been in order to connect that to like a number of years ago. We need to apply our cosmological model that sort of connects how the universe has been expanding over time. And so when we talk about a distant galaxy, we talk about it in terms of like, Oh, that's a redshift 10 galaxy or oh, that's a redshift three galaxy. And that's where we that's like how we order things in terms of how long ago that that thing was shining.
So you literally measure time by measuring space, measuring the size of the universe at that time. Yeah. Yeah. Yeah.
Then somebody has to headline about it. And so you have to you have to tell them. Right. And we have to do that calculation every time, right?
Like whenever there's a headline about like the most distant galaxy observed or you know, JLST is seen a galaxy, you know, whatever number of years we what we do is we say, okay, we see a galaxy at redshift, you know, 11.2 or whatever, and we have to go back to our models and stick it in a calculator and like calculate, okay, how many years ago was that? Yeah. So but what we do know is how much smaller the universe was when that light was emitted, which is it's weird that that's the thing we know. To have strange that strange that we know more about the size of the universe in the distant past than we do about time.
Like how many seconds have gone by? Yeah. Yeah. Time.
Okay, let's move on to another question because my head is starting to hurt and my stomach is also starting to hurt because I know that if everything just keeps getting further away from everything else, that is over time, what we know as a proper issue. This question comes through it's a level one emergency. And these are like, well, I know we have a level one emergency long term. It's gonna get it's gonna get uncomfortable eventually.
I mean, we're we're gonna talk about that more in the podcast. But yeah, yeah, we have we have we have a level one emergency, something that's going to deeply affect me or the people I love for my descendants. And I feel like cosmologically, we have a level one emergency. Yeah.
Yeah. Great. But I was ready to go for the moment things are pretty stable and will be for a while. But Nisha has a problem and things are not stable for Nisha because it's 2am and my bed just broke and I need to figure out how to fix it without turning the lights back on.
I don't know why. And I also don't know why you had to bust out your phone and email us instead of dealing with the matter at hand. But you never had a problem that you could distract yourself using your phone with because that's what people do. I guess I do do that a lot.
Nisha wants to know, can we not see stuff in the dark because everything looks black? If everything on Earth was always the exact same color, would we be able to see anything at all? I need a new mattress, Nisha. Wow.
If everything on Earth were the exact same color, would we be able to see anything? If there were no color distinctions, if everything on Earth was black, like deep, pitch, black, vanta black, painted, like matte black, it might be pretty hard to see stuff. If you had light, you could still see outlines, right? You could still see depth.
Not if it was like if it absorbed 100% of the light, you couldn't. Right. Which is very hard to get. Yeah.
So if you had like super vanta black, right? Like where there's no reflections at all. Yeah, it would be a proper issue. Yeah.
I think it would just look black, even if the sun was out. But if it was any other color, it would be shades of that color. So if everything was beige, it would be shades of beige, and that you would just see the world as a person who has like monochromatic vision, like a colorblindness where they can only see one color, you would see the world like that person does. How would you know to hate the franchise currently playing its trade in Milton Keynes?
Like would that mean that you couldn't have soccer? No, John, until your teammates were. We would find ways to tell the stories. It just be stripes versus solids.
Is these stripes versus solids? It's just old school style. You need two colors or stripes. Great point.
Oh, no. I don't know what I was thinking. This is why we have a proper scientist on the podcast. You do need to make the players different shapes.
I don't know how you're going to do that, but that's what you need to do. Yeah, you could have one jersey like circular, one jersey rectangular. That would be tricky. That would be tricky.
No, there'd be like a slight home advantage because you could wear a regular shirt instead of having to wear a big puffy shirt. Yeah, I like a Michelin man shirt. It could be any. Yeah, yeah.
You'd have to wear a state-fluff marshmallow on a shirt. Yeah. Like remember that AI thing where the pope was wearing that big, Balenciaga coat? Yeah, wear one of those.
It could be his crop tops versus regular shirts. I don't know if that's enough. I don't know if just glancing you could tell. That's good enough for me.
All right. I think I can put half the players in tight little crop tops. Tight shirts versus loose shirts might work. You could just make one of the players jersey's shiny.
What's shiny? Is that color? No, that's just reflection. Like we've established you're allowed to have reflections.
Right? It's not all bent to black, right? Yeah. So you make one of them like a shiny finish and one of them a matte finish and then you can easily to little part.
You could even make the stripes out of shiny versus matte if you really want to. They technically the same color. They just be different. Elbedo.
I think we've got a potentially new branding opportunity for AFC Wimbledon. The shiny and matte stripes. The expression comes from Kristin who writes, Hey, John and Hank, I recently got contacts and the internet is telling me I can't take naps in them. Kristin, Kristin, just ask your optometrist.
Don't go to the internet. Don't ask Google. Is that a real thing or is it like cleaning your ears with Q-tips for everyone says you shouldn't do it, but you can. No, Kristin.
Oh, no. You're approaching your facial health all wrong. Yeah. So it is very much like Q-tips in that people do it, but you shouldn't.
It depends on the length of the nap in my opinion. If you can take like a 15 minute nap, it's fine. Well, I can take like a three hour nap. I can't be the person to ask because I had contacts for like six months and then I lost them in a mosh pit and I was like, I'm not going to get those again.
Dr. Mack, do you have good vision or do you have? I have excellent vision. I have sniper vision.
I got an eye test once and the optometrist told me I should become a sniper. So that's a weird thing to come out of a medical appointment. It really was. You should kill it.
Yeah. Yeah. It was a little, I was a little concerned. You know, when that was the sort of obvious job of my special skills is like, whoo, you can kill people from a distance.
Congratulations. No, I don't want to do that. That's like there should be other things I can do. Does it help in cosmology at all?
Do you feel like you can like pick out a distant galaxy that others miss? No, it does help with flying though. It's actually very good for that. I can spot the airplanes from very far away and the people I'm flying with cannot see them.
You can't tell Katie Mack that sneezing isn't normal. I almost just sneezed and sneezing is very unusual for humans. It would have made me feel very disturbed, but I would manage to hold it in like a normal person would. I'm glad that you have supervision as a pilot.
I always forget that you're a pilot because I feel like we're friends and we have like fairly similar value systems and then you come out with also fly airplanes and I'm like, no, we're completely different than you're a pilot. Yeah. It was much closer to a dolphin than you are to me. It would be my presumption from the fact that you fly airplanes.
Like I have no idea what it is like to have an urge to fly an airplane. No, I don't have that one. It's a lot of fun. It was kind of a pandemic hobby.
I got a little stir crazy sitting at home too much and I needed to get outside and then there was this little airport nearby and I was like, well, I'll try that. Then I got really, really obsessed with it kind of unexpectedly. Can you fly like a 747? No.
I don't know how that works. No, I could fly a single-engine airplane, specifically a single-engine land airplane, not a seaplane. I am learning to fly a multi-engine, but that's just two engines and they both have propellers. They're not, I can't fly jets.
But if you had to, would you be one of the people who was like, I get like a plane. Right. Nobody else is like, what pilots are incapacitated? Yeah.
Right. The flight attendant is like, hey, can anybody land the 747? Do you like your odds? I like my odds better than anybody who's not tried it.
There's not flown airplane at all. Yeah. I think that there was a survey going around a while ago. Do you think you could land, like a bunch of things and a bunch of things and a pair of them was landing at 747?
And I felt like I have decent odds that I could get the plane onto the ground and we would at least mostly survive. I think that's, I think I had a new plane, but nobody would need new bodies. That's the hope. Yeah.
Yeah. So just to go through that questionnaire real quick, I could not fight a bear. And I am baffled by anyone who thinks they could fight a bear. I think I could talk a bear down off the ledge.
I don't think I could fight a deer. No, of course not. I could barely fight a raccoon and they would have any pounds. I think about this sometimes when I see a coyote and the coyote will be like, whoa, whoa, whoa, sorry man.
Didn't mean to get in your way. And I'm like, are you kidding? Like you could win. Like you would have a great chance.
Yeah. This is a lot of food I'm carrying around these two eggs. I definitely could not defeat a bear. I feel like I could, I could intimidate a bear, but my best self would be intimidating a bear.
Like my best self would be like, hey, bear and like raising my hands up and like, I'm a big, bad, scary human. You better walk away from me. My actual self would literally just crumble into a ball and wait for the bear to take me. You never know what's going to happen until it happens.
This is what you learned. I also could not land a plane, right? Like even with all the air traffic, people would be like, I think I might get lucky with that up. Yeah.
There's zero percent chance. I might get lucky with the bear. I have a zero chance. Or being like, oh, that hurt too much.
Like you poke me in the eye and like there's, there's berries nearby. Like you're not going to happen in a plane where the plane's like, oh, I'll just win myself. So it seems like you're having such a hard time. I feel like that's our biggest green flag.
Hank is like, we know our limitations. We don't know all of our limitations. That's true. That's a really good thing.
I keep running up into them all the time. Do you know the limits if you're knowing your limits? That's true. You do run up against the limits of your own talent a lot when you work in a creative, creative field.
You should take your contacts up before you take a map, but you probably don't have to. And this is the thing. This is the thing with the Q-tips too, where it's like, yeah, but you shouldn't. It pushes that wax in and then you have to get a doctor to take it out.
Or, yeah, or, oh no, use just use an ear candle. Those are totally effective. Or you could just sort of like wave a wand around it and pray. This question is from Rowan who writes, hi, John and Hank, I'm Rowan and I'm five.
Okay, first off, Rowan, no bragging. Okay. That's impressive that you can type in everything. That's great.
If I fly a real spaceship, how many minutes will it take me to get out of the atmosphere and into space so it's dark and stars and stuff? My dad says he has literally no idea. Also, what is literally? In my boat, Rowan, there's no way Rowan wrote that joke.
I'm sorry. I think Don wrote that joke. And it's a great joke. Yeah.
Can I tell you guys something that happened to me last night? There's no way five-year-old Rowan made it through that first question. To get to this one. I was reading what happened to you last night.
Reading or in a book. And then he moved all but one of his stuffed animals to one side of his bed. And then he interrupted me while I was reading the book. And he pointed to his pile of stuffed animals.
And he said, Germany. And I was like, what's happening right now? And then he pointed to the one stuffed animal on the other side of the bed. And he said, Jerf you.
Oh. It's pretty good. I was like, I mean, I mean, like a loud noise. Anyway, I think it's good.
But I think it's worryingly in the brand of Hank Green. Yeah. Like I'd like to see more in branching out into a little bit less of a punny land and more into best of like the moth joke. I have no more existential jokes.
Yeah, I'd love for him to be the new Norm Macdonald. But he's taking his own path. Rowan, it's just gonna matter how fast your spaceship goes. They can go all kinds of different speeds.
Can they though? Like don't they have to go fairly fast just to escape the atmosphere? Yeah, they have to go 11.2 kilometers a second. So I thought somebody might know the answer.
That's as well. What a pleasure it is to be potting with an actual expert instead of a professional spectator. I can't just go 11.1 kilometers a second. And just but just keep going.
I bet Dr. Mac has an answer. There's a little foresank. That's not that you've heard the answer.
It's the weak nuclear foresank. The strong one. It's definitely one of the forces. So if you just well first off, that's what you want to be going into.
Hank, let's just acknowledge what's happening, which is that a bunch of men who don't know anything are talking over a woman who knows a lot. Okay, so I know that 11.2 kilometers per second is escape velocity. I don't actually do rocket science. I do the other kind of complicated science stuff.
So I don't know like the details of what happens. So if you go if you are launching from the surface of the earth and you just give yourself a speed, it has to be 11.2 kilometers per second. If you are accelerating as you're going, you're going to be at a place where the force on you from gravity is a little bit less. And then that means that the escape velocity is a little bit less.
Right. So like the it gets a little bit tricky in terms of like as you're as you're moving the system is kind of dynamical, but you have to get enough energy to to at some point, like balance out the gravitational pull and the gravitational potential energy. And so the sort of the total kinetic energy that you get from going 11.2 kilometers a second in the direction away from the center of the earth, that's going to balance the gravitational potential of being pulled toward the center of the earth. And so that's that's the thing you're trying to balance.
But in terms of like what the speed looks like, it's changing when it has to be at what speed. Because you start out going that speed. So the real trick is how fast can you get to escape velocity and that you can do that acceleration at a number of different accelerations. Right.
Right. And that's why neither of these people is answering this question in a way that makes sense to me, let alone to you. Well, in terms of how many minutes it gets to the to get to space, like that's that's a different question, right? Because that just depends on how fast your spaceship is at the moment when it launches.
And I think that's like a few minutes, like it's not very long. Not as long as you say it's six minutes, Rowan. I think the answer to your question is six minutes. It could be faster if you don't mind being real squished for a long time.
But they got to take account of the squishable parts of the inside of the spaceship, which is going to be you Rowan, when you grow up and you're an astronaut. And it also doesn't take very long to get to the space station either. That's like a few hours. If you do it, you get to the international station.
Yeah. Just the part where you try and you have to match the speeds up. Yeah, I don't know how long it takes to actually dock. But like I've seen launches where they're like, they're there in six hours.
I think they can get there in like four depending on how they do it. They can get their friends. I'm really glad that I'm never going to experience it. Although it sounds like both of y'all might like it sounds like y'all might go to space if you have the opportunity.
I would totally go to space. Yeah, I put in my application. So now's I had a call a couple months ago and I put in my application. Are you serious?
Yeah. For space. It would be fun to have a friend who went to space, but not as fun as having all my friends on Earth. Yeah, no, I would be very scared.
I do like I have some friends who are astronauts. I have not ever watched one of them launch. That would make me very nervous. Yeah.
Yeah. I didn't even watch the web launch. That I was too scared. Yeah.
So if you were selected to be an astronaut, you would go. Oh, absolutely. Would you go to Mars? Yes.
Yeah. Reason. Yeah. Yeah.
Would you be in the first group to go to Mars? Sure. Sure. Yeah.
Well, it's almost even better because then you're like, then you're like, what's up for a man? Yeah. So like, I feel like if I were, if they made some kind of habitat on Mars, where you live for like years, you know, I would, I would not even necessarily require a return ticket. Like I would go.
I would just go. Wow. I mean, I wouldn't go if it was like you've got like three hours without the ability to return to Earth. Yeah.
I mean, if it were the sort of thing where they were like, you've got like a couple of days of oxygen. I'm not doing that. But if we're a long term, you know, habitat, yeah, I'd live the rest of Mars. You're going to die there and you probably going to die up there, maybe a little earlier than you would on Earth because the medical care isn't going to be the same.
Yeah. Yeah. Yeah. What's a few years, you know, like, like, how many things can you really do in life, right?
I love the idea of us sending like 10 people to Mars and then they just get old there. And eventually this is like 10, 85 year old on Mars. I am speechless. Yeah.
I'm a, yeah. I, that's not, I wouldn't sign up for that. I got a lot going on here. I just, I just think it would be worth it.
Like the, you know, the number of things that I feel like I could accomplish in life, you know, there's a number of things I could accomplish in life. But I feel like going to Mars would be higher priority than any of those things. It would be more interesting, cooler, more exciting than any of those things. And so like, yeah, I would replace a bunch of those, you know, Earth things for that with that.
Absolutely. But unfortunately, harder to do your fundamental cosmological work, like your work as, as important work to be done on Mars. I mean, I could, I could become a geologist, you know, I could go out and look at rocks and on my downtime, I could still, you know, read papers and do calculations, I'm sure. I think it'd be fine.
Yeah. But you are stuck with a computer that you get when they send you. That's true. I guess maybe less anymore computers.
They could, they could send more. Yeah. When I said earlier that I feel like if I were a person, you'd be closer to a dolphin in terms of our differences, I actually dramatically underestimated our differences. I hope this wasn't a way of our friendship, John.
It's like you're a person and I'm a two atara. Like I have no idea what it would be like to be willing to go to Mars, let alone be willing to take a one-way ticket to Mars. I mean, you don't think it would be exciting? Like, just exploration.
You know, it's exciting is like going for a walk in the woods and there's a small chance that you'll see a tough to tit mass. That's exciting. I'm very nervous. And I think like we don't think about this with the moon, but like we didn't really know enough about the moon to go to the moon safely.
It turned out okay. But like when the moon got into the, you know, into the lander, like some moon stuff, like I don't know, you're gonna have to breathe that stuff in. Was it made up? Is it better or worse than asbestos?
And that's how I feel about Mars. I'm like, you're, I'm gonna go to Mars and I'm like, I'm gonna be there for years. I'm gonna be breathing a lot of Mars. And I don't know that I want to breathe Mars.
There are, we have bits of Mars from meteorites. Right? And we have analyzed a lot of bits of Mars on Mars. Yeah.
And we've analyzed bits of Mars on Earth from stuff that's been sort of knocked off of Mars. And we're gonna, we're working on sample return. So, you know, I hope that that works. I, from what I know of Mars, I wouldn't want to breathe it.
I'm just saying sample return is a very far away away from human beings return. Yeah. Yeah. I'm anxious.
I'm like, we don't have to be honest. My armpits are pouring sweat right now. We're talking about hypotheticals, John. We're not, Katie's not leaving soon.
Katie could go to Mars anytime now. This is now, this is, this is a reality. I'm very present, concerned for John. Katie's willing to be the first, first part of the first group and, and she's a well-known astrophysicist.
They would be silly to turn down her application. There's like a 2% chance that Katie's going to Mars. Hey, Dr. Kate and Matt, what would you bring to Mars that you wouldn't need?
Oh, um, it's a great question. I would say books, but they're just so heavy. And probably I could get, you know, stuff on, on like Kindle or something. Um, hmm.
I don't know. I have to think about that. When I just like leave you like your childhood stuffed animal, like on a little hill. I mean, you know, I'm not that attached any, I used to have some that I was really attached to and I'm kind of like, they're in a drawer somewhere.
I'm not sure. I'm really not sure. I feel like I'd have to take something small and sentimental to remind me of my family or something like that. But I don't have anything that I can think of at the moment that's like, you know, I have to have that with me.
It reminds me that today's podcast is brought to you by the RobBlind Panic of your friend, potentially going to Mars, the RobBlind Panic of your friend, potentially going to Mars, a new, a new and exciting feeling. This podcast is also brought to you by the Earth's escape velocity, 11.2 something's per second. Clometers. We also have a project, from a message from Josh and St.
Louis to Rachel. Rachel, you are a profoundly capable person and I am so very grateful to have you in my life. I am proud of all the ways you are changing and growing. And I'm excited to support you always in your journey to make yourself who you want to be every new day with you is my new favorite day with all of the love in my heart, Josh.
That's so lovely. Thank you, Josh. Thanks for joining the project for awesome. This episode of Dear Hank and John's Brought to you by Shopify.
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See website for more details. This next question comes from Rory who asks deer greens and came back. When was the last time more than half of the global population was asleep? Was it okay?
And now that needs people are asleep right now? Rhymes with bedtime story Rory. I actually looked into this and every day most people are asleep for a little while. No way.
Yeah, because most people all live in a pretty, so like two things. First, you got to know that a lot of earth is the Pacific Ocean. It's hard to remember that because it's not on our maps, but it's half of earth. So those argue it is on our maps.
Well, it's not on a lot of them. We don't put it on a lot of maps because in order to make it into a map shape, we cut down the middle of the Pacific Ocean and then we sort of squish it out onto the sides. Okay. You're still there.
That's all right. Really, really, really don't want to let this one go because I'm right. It is there. It does say Pacific Ocean on the maps.
Yeah, it's not like we like canceled it or something. It's not like we don't put Hawaii on the maps because it's in the middle there. Yeah, we squish it all together. But anyway, there's a lot of earth that there's not a lot of people on because it's the middle of the Pacific Ocean.
But then the sleep band is more narrow than the wake band, of course, because people sleep for fewer hours than they are awake. But there's kind of you can sort of roughly gauge a sleep band that is about eight hours and it's about from, you know, maybe 11 o'clock at night to seven o'clock in the morning. And we're just sort of like fudging because around the edges that there's going to be people sleeping at different times in different places as well. But when that sleep band passes over Asia and India, there is a time when like pretty much when more than when like probably like 70% of people are asleep, which is wild.
And but also weirdly because of the Pacific Ocean, there is a time every day when like 95% of people are awake because the wake band is much bigger, which doesn't ever seem like that to me because I'm constantly trying to do business people in other parts of the world. And they are always asleep. It seems like to me, I can never call them. I wonder if the sleep band, you know, as population ages change, that's going to change too because old people don't sleep as long and babies sleep much longer.
Yeah, because the and there's just fewer babies and more old people every year on the earth. Yeah, that sleep band's going to sort of narrow a little bit. And also maybe move a little earlier in the day. Yeah.
All right, Hank, I got another question from Catherine who writes, Dear John and Hank and Dr. Mack, if Adams are mostly space, how can they support our wait? Why don't I fall through my chair? Questionably solid, Catherine.
So this is this is a great question. I feel like I'm not made of mostly empty space. So so first of all, defining empty space is complicated because there's like, because there's energy all throughout space that you can't really localize where particles are. So they're kind of like part of their wave function is sort of everywhere, you know, and so like you can't really say that an electron is not in a certain space.
It's just like there's a probability it's in that place. So so that whole thing is a little bit, you know, unclear, but but the reason that that things feel solid is not because anything's like actually touching. It's because of electrostatic repulsion. So like when you're touching something, what's really happening is that the electrons in your fingers are pushing against the electrons in the other thing.
And they're pushing with with electricity with with the electrostatic force, electrostatic repulsion, electromagnetism. So it's like, is it like magnets where there's like like an electron is negative and electron is negative and so you can't push two negatives together? Yeah, it's like that. I mean, it's not magnetism, it's electricity, but it's the same kind of like repulsion, right?
And so so when when you're trying to, when something feels solid, it's because there you have those those atoms are packed together and the electrons are on the edges and they're pushing against stuff. And and so, you know, the reason why, for example, in Intrino, which is a tiny particle that has no electric charge can pass through the earth without noticing is because it doesn't have any electric charge. So it doesn't interact in that way. So the earth is not solid to a neutrino or vice versa.
And can it just pass through an electron shell? Yeah. Yeah. So in the space between where the electrons are and the proton is and the nucleus is it could just go right through that space.
Yeah. I mean, it can go through a neutrino can go through like a light year of lead with only a tiny chance of interaction with anything. Are there neutrinos going through me right now? Oh, yeah.
Oh, trillions of trillions. Yeah, yeah. Are you serious? Yes.
I'm being invaded. Yeah. But like by like being penetrated by neutrinos, like by the trillions. You're coming in and out there like their like exit wounds, the whole thing.
So it's like it's like a stream. So the most of them are coming from the sun. So the sun is there. Yeah, they're coming mostly from that direction and just passing right through you and not noticing and you don't know how to throw the whole earth and then passing through somebody else on the other side.
Yeah. I think in your lifetime, there's there's a chance that you're likely going to have like one or two neutrino interactions in your body, something like that. It's a very small number. What do those do?
What do those do? It doesn't? So I don't, you know, I think like, I think there's a chance it could like knock an electron a little bit, but you're not, it's not going to be, it's not going to be noticeable. I mean, you're going to be hit by other stuff.
Yeah, they're bigger worries. Like you're going to be hit by muons and other other other other countries that are more likely. Sorry. Cosmic rays.
Tell me more. Hank, I don't want to listen to you right now. Dr. Mac, what am I going to be hit by?
Yeah, you're going to be hit by cosmic rays, like high energy electrons and muons and some protons and, you know, high energy nuclei from time to time. Like you'll be hit by other stuff for sure. Yeah. But but not not so much energy knows.
I just like smash by it. I didn't know any of this. Yeah. Yeah.
And if you're, if you go up to like high altitude, you'll get hit by more cosmic rays. So like if you're in a plane or in a spaceship, you're going to get. That's why I stay near sea level. Yeah.
I was like standing right underneath the aurora borealis. Was I getting extra? So I think the whole earth was getting extra. I don't know.
I don't know that that being able to see the aurora specific because there were is like what I mean probably a bit like just because because like what's happening there is that these charged particles from the sun are smashing into the upper atmosphere and you know they're kind of being funneled around by the magnetic field, but they're smashing into stuff in the upper atmosphere and lighting it up right there. They're sort of exciting those those atoms in the upper atmosphere. So so like what you're seeing stuff because there's just way more flux of cosmic rays from this this plasma thrown off by the sun. So the fact that there is an aurora happening, yeah, you're probably going to be hit by more stuff at that time.
I thought about that actually because some of my friends were like going flying, you know, during the aurora and some people got some nice views and I was like, are you getting way more cosmic rays? You go up to that. Yeah. I mean, it definitely messes with some of the navigation equipment for planes.
So you have to be a little careful about that. But but yeah, I mean, I think it's a little worse. I think, yeah, neutrinos. I mean, yet one more reason to stay here on Earth.
Yeah, it's such a good planet. The best planet from the perspective of getting attacked by cosmic rays. It's protecting us so well. That's true.
And on Mars, you don't you don't have the magnetic field moving stuff around. You don't have a thick atmosphere to stop some of that stuff. Like the flux of radiation on Mars is way worse than here. Yeah, you don't get to live in a nice pretty dome on Mars.
You got to look underground. You're living under the dirt. Yeah. Yeah.
Wow. Okay. But you still do it. It's time to transition to the news from Mars and AFC Wimbledon Mars, of course, Dr.
Max future home and AFC Wimbledon home to my heart. I'd like to go first if I might. Okay. We've signed our first new player of the new season.
It's the off season, but we've already signed someone. It's exciting. I don't know how excited to be because this guy, Matty Stevens. So we signed a guy named Matty Stevens.
He got relegated last year, but he scored 18 goals while being relegated, which is pretty good. Well, it's relegated me like he was on a team and they keep them off. No, he was on a team and the team got demoted to the league below. Gotcha.
Their name was Forest Green Rovers, and they got demoted to the league below, but he has no longer Forest Green Rovers. They've taken their name away from them. No, their name is Forest Green Rovers. It's just now they're no longer in the football league, so you can't play as them in FIFA.