Daniel and Kelly’s Extraordinary Universe - Listener Questions #24

Episode Date: December 11, 2025

Daniel and Kelly answer questions about Jupiter and circadian rhythms.See omnystudio.com/listener for privacy information.

This is an I-Heart podcast. Guaranteed Human. I know he has a reputation, but it's going to catch up to him. Gabe Ortiz is a cop. His brother Larry, a mystery Gabe didn't want to solve until it was too late. He was the head of this gang. You're going to push that line for the cause. Took us under his wing and showed us the game, as they call it.

When Larry's killed, Gabe must untangle a dangerous past, one that could destroy everything he thought he knew. Listen to the brothers Ortiz. the IHeart Radio app, Apple Podcasts, or wherever you get your podcasts. Hi, Kyle. Could you draw up a quick document with the basic business plan? Just one page as a Google Doc. And send me the link.

Thanks. Hey, just finished drawing up that quick one-page business plan for you. Here's the link. But there was no link. There was no business plan. I hadn't programmed Kyle to be able to do that yet. I'm Evan Ratliff here with a story of entrepreneurship in the AI age. Listen as I attempt to build a real startup run by fake people.

check out the second season of my podcast shell game on the iHeart radio app or wherever you get your podcasts what are the cycles fathers passed down that sons are left to heal what if being a man wasn't about holding it all together but learning how to let go this is a space where men speak truth and find the power to heal and transform i'm mike delarocha welcome to sacred lessons Listen to Sacred Lessons on the IHartRadio app, Apple Podcasts, or wherever you get your podcasts. The show was ahead of its time to represent a black family in ways the television hadn't shown before. Exactly. It's Talma Hopkins, also known as Aunt Rachel.

And I'm Kelly Williams or Laura Winslow. On our podcast, welcome to the family with Telma and Kelly. We're re-watching every episode of Family Matters. We'll share behind-the-scenes stories about making the show. Yeah, we'll even bring in some special guests to spill some tea. Listen to Welcome to the Family with Telma and Kelly on the IHeart Radio app, Apple Podcasts, or wherever you get your podcasts. If the Earth and Jupiter were to collide, what would happen? How would we die? Circadian rhythms are corrected using the sun's light. If you live at the bottom of the sea, how would you?

How do you get that right? How big a planet could we use rockets to escape? If we'd evolved on Jupiter, would we be planet-bound apes? Whatever questions keep you up at night, Daniel and Kelly's answers will make it right. Welcome to Daniel and Kelly's extraordinary universe. With an emphasis on Jupiter, it seems. Hello, I'm Kelly Weiner-Smith, and I study parasites and space. And clearly, Jupiter is the best planet.

Hi, I'm Daniel. I'm a particle physicist. And yes, Jupiter has the most particles of any planet. And does that make it the best as a particle physicist? It makes it the mostiest, I guess. You know, I think people underestimate, like, how much of the solar system is just the sun and Jupiter. like mostly it's just the sun and then you want to add Jupiter our right to round it up to 99.9.9 and everything else is just details. We're really just hearing somebody else's party. Oh man. That's a little, it's a kind of a bummer of a way to start our episode. We are all insignificant. No, I think it tells you something though when you look at the depiction of the solar system and all the planets are like big and obviously it's not to scale. But it tells you something about what we find important, right? Clearly, we are important in the solar system.

So we zoom up. It's like that cover of the New Yorker where they show like a map of the United States from the New York City perspective and it's like mostly Manhattan and then like a few details. And that's ridiculous and you laugh at it

but that's exactly what we're doing about the planets, right? Well, but you know, on the one hand we've known about Jupiter for much less long than we've known about Earth and, you know, we're here on Earth makes it easier to study. I'm going to go ahead and stand down

on defense of Earth. And the Earth-centered view of the world. I'm not saying it's wrong. I'm just saying it reveals something about our biases, right? The things we think should be presented first. I grant you that. But there's probably, you know, solar systems that are bigger than ours. And maybe we shouldn't even be talking about our solar system at all.

And where do you stop, Daniel? Where does it end? It never ends, Kelly. There's no bottom to the philosophical rabbit hole. Oh, my goodness. But we love going down rabbit holes, especially rabbit holes that you are. interested in. So if you have a question about the nature of the universe or how something works or how little squishy critters make their lives, please write to us with your question. We would

love to answer it here on the pod. And today, we're answering three super fun questions from listeners. That's right. So let's start with our first question from Brad. A great question about Jupiter, of course. Hello, Daniel and Kelly. I have a question about planetary collisions. Jupiter is classified as a gas giant planet and is known to sweep up many stray masses flowing through our solar system. If something were to happen to cause Earth and Jupiter to collide, what would happen at impact?

Is the mass of Jupiter large enough to spaghettify Earth and destroy us like a black hole? Or is the likelihood of a direct collision too small and Earth would just be ejected from the solar system if we'd become too close? Or is the surface of Jupiter really a gas and Earth would just pass into the inside of Jupiter and basically be absorbed

and Earth would just coast through a dense atmosphere of gases and would eventually hit a solid core. Thanks. Brad from League City, Texas. So, Kelly, do you think Brad is a supervillain to planning to push Earth into Jupiter or threatened to? You know, I did wonder about that when I was listening to this question. I'm a little concerned.

And, you know, one, I'm a little concerned in general now that this is something, you know, on my radar to worry about. And then, too, I'm a little worried about Brad in particular. A couple red flags here. Yeah, that's right. I'm not sure in his question, And if he's worried about this or excited about it, he's like, hmm, let's do the experiment.

Yeah, yeah, hard to say. Hard to say. Maybe we shouldn't give him the answer. Exactly. I worry about that. Like, when the kid wrote to me and asked me what it would take to blow up Mars, I was like, hmm, should I really be telling a 10-year-old how to destroy a planet? But on the other hand, you know, you hope they don't wield that sort of power to do anything about the information. Who knows what today's 10-year-olds will do in 20 or 30 years, right? That's true. That's true. And you'll be to blame, Daniel. I accept that blame. But today we're here to answer Brad's question as a hypothetical science question about something we hope will never happen, which does reveal a lot of really interesting solar system physics. So let's get into it. And I think we should probably start with what is spaghettification, because that is, you know, clearly one of the best scientific terms our community has ever come up with. Absolutely. Spaghettiification is usually used to describe what happens to an object as it approaches.

which is a black hole in that you won't just fall in, you'll be torn apart into spaghetti, essentially, before you actually fall into the black hole. And this doesn't just happen around black holes. It happens all the time in strong gravitational environments. In fact, it's happening to you right now and it's happening to the moon. It's the result of tidal forces. And the reason simply is that the force of gravity depends on distance. So if you're falling into a black hole or you're orbiting a planet or whatever and your feet are closer than your head, then your feet have a stronger gravitational force on them than your head does. And effectively, that's a force pulling your feet away from your head.

And if that force is strong enough, it will pull your head off your body or your feet off of your head, depending on your perspective. I'm going to be honest here. I feel like you've sort of de-excitified spaghettification for me by being like, it's just a kind of title force. It's like what's happening to the moon. I'm like, oh, but I don't spaghetti. That's not what I imagined in my head.

Oh, you're imagining some sort of black hole magic? Yes, yes. I thought this was a specific black holy thing. And that spaghettification really, you know, required you to be thin like a noodle. But okay. All right. Physics has been ruining things since 1584 or whatever. Oh, and what happened in particular in 1584, Daniel? I just made it that date. I was referencing one of Zach's comics. I can't remember what year he had on that or why he picked it. I think it was supposed to be like L.A. was experiments or bacon or somebody like that. Anyway, that. point is that tidal forces are a thing. So if you approach Jupiter, for example, then the difference in forces between one side of your object and the other side of your object, those are the tidal forces. And that's why we have tides on the earth, because the moon pulls on one side

of the earth more strongly than on the other side of the earth, making it a little bit of a football. And the earth does the same thing to the moon. And that's why the moon is locked in place. It's called tidily locked because it's a little bit of a football, and it's hard for it to spin away from having the pointy bit of its football aligned with a pointy bit of the Earth's football. Okay, but so Jupiter is much bigger than the moon. So, you know, you said that when the force gets hard, it could like pop a head off. Is Earth's metaphorical head going to pop off towards Jupiter? Or is it just going to get like weird tides? Yeah, so there's a boundary called the Roche limit. If you get closer than that, you get torn into pieces. If you're further away from

that, you don't. And that's why some planets have rings and some planets have moons. If your moon is further away than the Roche limit, it stays together. Local gravity wins over the tidal forces. If you get too close, then it gets torn apart into a ring because the tidal forces overcome the internal gravity. So that's the Roche limit. So what happens as the Earth approaches Jupiter? Well, the roche limit for a solid body like the Earth is actually inside the cloud tops of Jupiter. Jupiter is a gas giant, and the outer layer is like 50 kilometers of just clouds, below which you have like gaseous hydrogen,

and then liquid hydrogen, and then this crazy helium neon rain, and then an ocean of metallic hydrogen before you get to the icy, rocky core. So the Earth would sink into the clouds without getting torn apart. It would get torn apart after it already passes into the clouds. Okay, so at that point we are closer to Jupiter than Jupiter's rings, right? So Earth's not going to become like a ring of Jupiter. It's going to get torn apart and then rain down on Jupiter. Is Jupiter the planet that has the diamond reign?

I think that's Saturn. Oh, all right. He's so disappointing. Jupiter, yawn. Come on, Jupiter. Step up your game, man. All right, so now we have a collision of an entire Earth, right? It's whole.

It has not been pulled apart by the tidal forces of Jupiter. And it hits Jupiter. And Brad asks, like, what's going to happen? Is it going to pass in and be absorbed to hit the solid core? And you're definitely not going to make it all the way to this. solid core because even though Jupiter is a gas giant and has like layers and layers of hydrogen, that hydrogen is dense and atmospheres have friction. Even here on Earth where atmosphere is pretty low density compared to the Jovian atmosphere, you know, there's re-entry. If a rocket or an asteroid

tries to enter the Earth's atmosphere, there's a lot of friction from the atmosphere and you get all this heat and most things that hit the Earth's atmosphere don't make it to the surface. Same principle applies when the Earth hits the Jovian atmosphere. Okay. And so what's going to happen is you're going to compress the jovial atmosphere, which is going to heat it up, turn it into plasma, and that's going to vaporize the crust and the mantle of the Earth. Shoot!

Yeah, bad. And so essentially a massive energy release here. Did a little bit of the back of the end globe calculation, and assuming that the Earth hits at like 60 kilometers per second, which is, you know, fast but not super fast for solar system speeds, you're going to release 10 to the 18 megatons of TNT. Oh, wow. And you might be like, I don't know what that number means. Well, the Hiroshima explosion was 15 kilotons.

This is 10 to the 18 megatons. So it's like so much bigger. And, you know, I mean, the entire Earth is essentially a bomb. And a lot of that mass is converted into energy. So it's an enormous explosion. You're going to get like a fireball rising above the surface of Jupiter. It's going to be much bigger than the volume of the Earth. And you're going to have shock waves in the jovian atmosphere, which probably will,

last for years. You may even leave a spot on Jupiter. It's very unlikely you're going to make it all the way to the core because you've got lots of dense layers before you get there. But yeah, it's going to be a huge impact. But remember, Jupiter is huge compared to the Earth. Like, it's so much bigger than the Earth that even though this is an enormous amount of energy and would devastate the Earth, vaporize essentially, Jupiter is going to mostly shrug it off. Oh, man, that's a little insulting. Every human I've ever known or loved disappears and Jupiter's like, meh. Okay, well, so say at this point when this happens, we have a self-sustaining settlement on Mars. If the Martians were like in the right position, could they see this? Or would

the act of Jupiter moving towards Earth have destroyed Mars on the way or thrown Mars off orbit? This is probably unfair. It's a totally different question. But I'm asking you anyway, Daniel. Oh, I see. Well, I was imagining that the Earth is getting tossed into Jupiter rather than Jupiter is like bullying its way into the inner solar system. Oh, okay. So the Martians have a nice view of Earth shooting by, and then they, yeah, they could watch Jupiter as it gets impacted. In fact, we had ringside seats to a similar event in the 90s.

And I think you told me that you were at a telescope watching that, right? Yeah, I had a super fast camera hooked up to a telescope to watch this collision. This is in the mid-90s, comet Shoemaker Levy impacted Jupiter and created all these fireballs. Now, the comet did not nearly the size of the Earth, of course, but It's still very, very dramatic. And what happened is that this comet, which used to be orbiting the sun, got captured by Jupiter.

So now it was orbiting Jupiter sometime in the 60s. And in the early 90s, it passed very close to Jupiter. So Jupiter tore it apart. It went within the roche limit, not actually within the clouds. The roche limit, weirdly and confusingly, depends on the object. Like if you're made out of diamond, then your roche limit is much closer. You have to get much closer to get torn apart than if you're made out of, like, cotton candy. And so this comic got torn apart into 21 pieces, which they labeled A, B, C, D, all the way up

to W, NASA, very creative. Of course they did. That was an opportunity for creativity, so they had to pass it by. And then it swung around one more time. And over six days in 1994, each piece took turns smacking into Jupiter. Really amazing. And everybody on Earth was like turning their telescopes to it and watching these pieces hit. And the biggest spot is the one where the G fragment hit. And so you can imagine what that spot might be called. I was just thinking that, but this is a children's show. Exactly. And created a huge dark spot.

There was a fireball and a dark spot. The width of the Earth. Wow. Now, this fragment is a piece of a comet, which is tiny compared to the Earth, but it created a big spot the size of the Earth that was visible for a year. So we've seen this kind of impact much smaller. So essentially to scale this up much more dramatically, but still small compared to Jupiter. Amazing.

I wish I had watched them. That wasn't on my radar because I didn't have amazing friends like you back then. You wouldn't have let me go astray, but that's all right. I was in college at the time, and I was home over the summer doing a research project on plasma physics, and we had a super fast camera that we were using to image what happened when you drop a little pellet of fuel into the fusion plasma. And the guy I worked for also had a telescope, and he was like, let's point this thing at Jupiter. So we connected the camera to the telescope, pointed to Jupiter. and we had one of the fastest digital cameras around at the time for scientific applications.

So we were hoping to have like the highest time resolution photographs of this impact. But just as the impact was going to happen, it went over the horizon. So we got pictures of the fireball rising over Jupiter, but not the impact itself. But it was a lot of fun anyway. So wait, this was 94 though, is that right? Yeah. Okay, so I was 12. So I probably, I was listening to Silverchair.

and I didn't care about anything other than silver chair. Important stuff. I felt that way at the time. The rest of us were learning about the future impact of Earth on Jupiter. But, you know, whatever. Well, I was having a good time. So I wouldn't change it for anything. All right.

Brad asked if there was any chance we'd get ejected from the solar system. But you didn't mention that as an option. So that's not something that would happen? It could happen. It depends on how accurately Brad and his supervillain team aim the Earth at Jupiter. One possibility is it hits Jupiter, right? Another possibility is that it's captured and it orbits Jupiter. And this has happened to a bunch of stuff we think that many of the moons of Jupiter didn't form with Jupiter, but were captured by it later. But it's a little

bit unlikely because for that to happen, you have to be only at the right angle and the right velocity at the right location to get the orbital mechanics to work out. So more likely you're either going to hit Jupiter or you're going to get ejected from the solar system because you're going to have a gravitational interaction with Jupiter, which is then going to throw you out of the solar system. All right. Well, one way or another, I think someone should be keeping a close eye on Brad. And let's see if our answer changes Brad's mind about whether or not this is a good idea. Daniel and Kelly, I absolutely love this response. I assure you that I am not a super villain and have no plans to destroy the planet. It sounds like we would get to watch as we pass into the gas cloud layer

before we heat up and explode. I like to know that. that we would at least have a little impact on Jupiter. I think all we need to know now is where Michael Bay wants to set up the camera to catch the greatest collision of all the time. Thanks for all y'all do. Hi, Kyle. Could you draw up a quick document

with the basic business plan? Just one page as a Google Doc and send me the link. Thanks. Hey, just finished drawing up that quick one-page business plan for you. Here's the link. But there was no link. There was no business plan.

It's not his fault. I hadn't programmed Kyle to be able to do that yet. My name is Evan Ratliff. I decided to create Kyle, my AI co-founder, after hearing a lot of stuff like this from OpenAI CEO Sam Aldman. There's this betting pool for the first year that there's a one person, billion dollar company, which would have been like unimaginable without AI and now will happen. I got to thinking, could I be that one person?

I'd made AI agents before for my award-winning podcast. Shell Game. This season on Shell Game, I'm trying to build a real company with a real product run by fake people. Oh, hey, Evan. Good to have you join us. I found some really interesting data on adoption rates for AI agents and small to medium businesses. Listen to Shell Game on the IHeart Radio app or wherever you get your podcasts. I'm Robert Smith, and this is Jacob Goldstein, and we used to host a show called Planet Money. And now we're back making this new podcast called business history about the best ideas and people and businesses in history. And some of the worst people, horrible ideas and destructive companies in the history of business.

Having a genius idea without a need for it is nothing. It's like not having it at all. It's a very simple, elegant lesson. Make something people want. First episode, how Southwest Airlines use cheap seats and free whiskey to fight its way into the airline business. The most Texas story ever. There's a lot of mavericks in that story. We're going to have mavericks on the show.

We're going to have plenty of robber barons. So many robber barons. And you know what? They're not all bad. And we'll talk about some of the classic great moments of famous business geniuses, along with some of the darker moments that often get overlooked. Like Thomas Edison and the electric chair. Listen to business history on the IHeart Radio app, Apple Podcasts,

or wherever you get your podcast. For 25 years, I've explored, what it means to heal, not just for myself, but alongside others. I'm Mike De La Rocha. This is Sacred Lessons, a space for reflection, growth, and collective healing. What do you tell men that are hurting right now? Everything's going to be okay on the other side, you know, just push through it. And, you know, ironically, the root of the word spirit is breath.

Wow. Which is why one of the most revolutionary acts that we can do as people just breathe. Next to the wound is their gifts. You can't even find your gifts unless you go through the wound. That's the hard thing. You think, well, I'm going to get my guests. I don't want to go through all that. You've got to go through the wounds you're laughing.

Listening to other people's near-death experiences, and that's all they say. In conclusion, love is the answer. Listen to sacred lessons as part of the My Kutura Podcast Network, available on the iHeart Radio app, Apple Podcast, or wherever you get your podcast. Hi, I'm Dr. Priyank-Wali. And I'm Hurricane DeBolu.

On our new podcast Health Stuff, we demystify your burning health questions. You'll hear us being completely honest about our own health. I'm talking about very serious stuff right now, and you're laughing at me. And you'll hear candid advice and personal stories from experts who want to make health care more human. Sometimes you're there to listen, to understand, to empathize, maybe to give them an understanding or a name for what's going on. That helps people a lot. understanding that it's not just in their head. We are breaking down the science,

talking with experts, and sharing practical health tips you can actually use in your day-to-day life. From when to utilize and avoid artificial light to how to sleep better. Everything you need to know about fiber and how to poop better. How to minimize the effects of jet lag

and how to stay hopeful in times of distress. We human beings, all we want is connection. We just want to connect with each other. We want to make health less confusing and maybe even a little fun. Find health stuff on the iHeartRadio app, Apple Podcasts, or wherever you get your podcasts. All right, we're back and we're answering questions from listeners. Now we're going to take a break from Jupiter-themed questions and think about sleeping.

Here's a wonderful question from one of our Discord listeners. And if you're not on Discord, come join us on our Discord channel. We have lots of fun conversations about science. We answer questions on there. Other people answer questions on there. We have wonderful moderators to keep it a really happy, fun family. Come, join us for Science Chats on Discord. You can find a link on our website.

Anyway, here's the question from our listener. In the episode about Sleep and Dreams, the topic of circadian rhythms in various animals came up. I was curious how circadian rhythms work in animals that never see the sun, like cave dwellers or various deep sea creatures. creatures. Thanks for taking the question. Looking forward to the answer. Bye. All right. T to the J, uh, uh, on discord. I, I got to say, you know, this question came in and I thought, all right, circadian rhythms. I'm a biologist. I should be able to knock this answer out pretty quick. Uh, I don't know anything about circadian rhythms. It turns out. Oh, no. Biology is a big field. Is that what I'm saying. And, uh, but I really enjoyed the opportunity to

get to dig into circadian rhythms. Again, this is one of the things I love about the questions we get from listeners. There's so many things I thought I understood, and then they give me a chance to dig into them, and I learned so much. So circadian rhythms. Circadian comes from the words Circa Diaz, which means approximately a day, and I don't know, maybe that's Latin. I probably pronounced it wrong, but you all know what I'm saying, so it's all right, we're good, and nobody expects me to pronounce things right at this point. That's not what they're here for, Kelly. That's not what you're here for. So circadian rhythms are like internal rhythms that happen on an approximately 24-hour cycle and they're entrained or they're sort of like synced up based on

outside signals like light. But why do you say approximate? I mean, the earth cycle is pretty crisp. Wouldn't we do best being closely linked to it? Why are you saying approximate? Because, you know, it's just not perfect. And some people have cycles that are a little bit longer than 24. Some people have cycles that are a little bit shorter than 24. We think this contributes to why some people are morning people and some people are night people. And then if you're talking about organisms other than humans, you can get some other slightly different sorts of signals that are approximately 24 hours. So then what parts of the human body are affected by it? Obviously, you sleep in this sort of 24 hour cycle. Is there other stuff going on also? Yeah, lots of things. So like sleep is

important. Metabolism is also important. Like your body temperature is impacted by circadian Rhym metabolism? So is that why I shouldn't eat chips at 10 p.m.? That could partly be it or be involved. I think cortisol is to some extent involved in helping with digestion and stuff. And so your cortisol kind of peaks at times of day when you're like expected to be hungry and expected to be eating. What's cortisol? Cortisol is a hormone that folks usually associate with recovery from stress. So when you get stressed out by something, your body releases cortisol. And then cortisol helps your body sort of return to homeostasis or like a normal state after you've been stressed out. Cortisol sounds great. I should get some more of that. Well, if you're like, you know, running away

from a lion, cortisol is great. Like it releases a bunch of energy all at once so that you can outrun the lion and then when you're in a safe spot, it helps you sort of return to normal. But if your cortisol level is elevated for a very long time, you can start having diseases because you're constantly in a stressed out state. So cortisol is more supposed to like get you out of a intense acute situation, but if it's elevated chronically, it can be bad. And there's a really interesting book on this called Why Zebras Don't Get Ulcers by Robert Sapolsky. Cool. All right. Yeah. Well, I wonder if zebras go to my physics faculty meetings if they feel stressed out and need cortisol afterwards. Oh, yeah, faculty meetings. I think what I'm stressed

out about in faculty meetings is that I could be spending my time way better doing anything else. But, you know, I haven't had to go to faculty meetings for a while, so that's great. But our question today is not about silly arguments in physics faculty meetings. It's about the rhythms of the body. So you're telling us that these things happen and impact sleep, metabolism, and temperature. But what's the mechanism for it? Like, what is driving it? Yeah.

Okay. So most of the work that we've done to figure out the mechanism has been done in organisms like mice and fruit flies. But here's how we think that it works, how we're guessing that it works in humans based on what we've seen in lab animals. So there's a little part of your brain called the hypothalamus. And inside of the hypothalamus, there's a little. region called the super kiosmatic nucleus or the SCN, because I'm not going to try saying that a bunch of times. It sounds a lot like super-cali-pragilious, but all right.

Yeah. I hear that every time you say that now. Okay. No one's going to be able to pay attention to the rest of the episode. They're going to be singing just like Mary Poppins. But try to focus, people. All right. So you've got the SCN, and the SCN is connected to the optic nerves.

And so optic nerves, these are the nerves that go to your eyes. And so we've talked in the past about how. your eyes have specialized cells called rods and cones and those help you detect like patterns and colors and to see your world. But you also have cells that just detect

the intensity of light. And those cells send information through your optic nerve back to the SCN and your brain uses that information to tell the rest of your body how the rhythm should be working. And so it does this by either sending messages

through the nerves or by directing the production of hormones that will then go to the rest of your body and talk to your cells and basically say, okay, hey guys, it's morning. And when it's morning, your body increases its heart rate, increases its blood pressure, increases temperature, your body is not making melatonin at this point. Melatonin's associated with sleep. So this is generally how your body collects the information about what should be setting the timing for the rhythm. But each one of your cells also has its own circadian clock. So we have these special cells in our eyes

instead of just using the information which already exists in the rods and cones, we like evolved a separate pathway just for this. Wow, this is pretty weird engineering. Well, but it's detecting something different. Your rods and your cones are detecting like colors and, you know, patterns of like dark against light and stuff like that.

These cells are just detecting the intensity of the light that's coming in. So you're like, oh, it's dawn now or oh, it's noon. And so it's detecting that. I feel like I could write a computer program to extract the same information from the data produced by the cones and the rods, but that's fine. Obviously, the brain is not engineered by a physicist. And that's not how evolution works. Evolution doesn't say, okay, yeah, I'm going to start from scratch and come up with the best system.

It's like, well, what do I have and how can I work with it? I just think it's a fascinating clue that something happened there that this is what we ended up with. Just another example of how, like, obviously, this is not well organized, just what kind of worked. So do we know this because we've, like, done studies in mice where we've, like, tweaked those cells or got rid of those cells or, like, shined light on those cells or something? And it's changed the way the mice behave. Yeah. So if you mess up a mouse or a flies, SCN, then they'll start free cycling. So essentially, they won't show these 24-hour cycles.

They're not so expezealidocious anymore. That's right. That's right. It's truly quite atracious. All right. So that's one. Oh, wait, hold on. You got.

Okay. That was pretty good. That was pretty good. Yeah, you're begrudgingly patting me on the back there. I was so excited by my next question. I didn't even register your joke, but that was excellent. Ten points for Kelly for everybody who's keeping score. So you're telling us that not only these light signals tell us when to be fragilistic,

but also the rest of our body responds in some way. Yeah. So first, I just want to mention real quick that organisms from bacteria to humans show these clocks. And so this is like not every organism, uses their SCN, and so this sort of like feeds back on our conversation about how you just use what you have. This has been going on for a really long time. Anyway, so not every single cell has its own circadian clock. I misspoke earlier, but many cells, even if you take them out of the body and you put them in like a petri dish, they will show like a 24-hour schedule for the activities

that they do, like they'll repair DNA at a certain time, you know, stuff like that. And so here's how we think that works. So your cell is making a protein called clock protein. The clock protein at dawn moves into your nucleus where the genetic information is stored and it binds to literally thousands of different sites on your DNA. And when it binds, it's telling your DNA to start making certain things. And it could be making certain hormones. Like it can say, hey, start making that cortisol. It could start doing, you know, whatever is needed to increase body temperature or heart rate, et cetera. So thousands of things are turned on when your clock proteins go in there and bind to lots of different spots. Another thing that's being made, though, during the

course of the day are proteins that will shut this down. And these proteins are called period proteins. And so the period proteins will build up over the course of the day because the clock proteins said, hey, start making these. And at some point, they've built up to high enough levels that now they go into the nucleus and they pull the clock proteins off of the DNA. And that stops all of the stuff that the clock proteins had been turning on and getting made. As the night goes on, the period proteins break down and go away. And then the next morning, the clock proteins go back in and the cycle starts again. So like many clocks, you have some sort of process, which has a natural time scale built into it, right? And so there's this chemistry where things are sloshing back and forth and naturally at the same rate as our 24-hour cycle. Is that what's happening? Yeah. Yeah. That's a good summary. And I saw you looking something up, was I wrong about something, or was it unrelated? I was wondering if clock was an acronym for something in a really tortured way. Oh, okay. All right.

I was hoping it stood for something ridiculous. Okay. Because if it was a physics acronym, it definitely would have a ridiculous name. Got it. So light is important for determining these cycles. Right. But it also is fine-tuned by things like the temperature you find yourself at, when during the day you're eating. And these cues are important for other animals as well.

So it's not just light, but light does seem to be a super important factor. So it's interesting you have several different kind of things going on. Can they get out of sync or is there something that tries to keep them in harmony? Well, so once you develop a cycle, your body is pretty good at keeping that cycle going. So like if you stayed in a dark room for two days, your body would still have some of its normal cycle. It's not like it breaks down immediately. But over time, if you deprive your body of that light cue or you mess your cues up, then you can start having problems. So, for example, if you work the night shift, you know, any of us who have had jet lag have had like a temporary period where our circadian rhythm was like, something's not right.

And then it's had to get back to normal. But being off of your normal circadian rhythm too often, for example, working the night shift increases your risk of diabetes, obesity, depression, dementia, and some kinds of cancer. So these circadian rhythms seem to be important for a lot of reasons, at least for humans. Wow. And how widespread are circadian rhythms? So everything on Earth has a circadian rhythm? Well, so like bacteria, humans, plants, lots of stuff has circadian rhythms. But our listener had a really great question, which is, how on earth do you have a circadian rhythm if you live in a place with no light? Yeah. And so the three different situations that I looked into where there's no light are if you are, for

example, at the North Pole during the time of year where you don't see the sun. There's like, I think, a couple months where that's the case. If you live in a cave, or if you live in the deep sea. And then there's also organisms like naked mole rats that live underground, but I think naked mole rats can peek their heads out every once in a while and see the sun to help entrain their clock. So they get some light cues still. So let's start with if you live far north. Yeah. So one thing that's important to note, which we touched on just a second ago, is that clocks don't go away immediately just because you're in total darkness. So at the start of the long night, they're probably fine because their body hasn't like forgotten the rhythm yet.

And during the time of year when it's all light, they're probably also fine because the intensity of the light still changes over the course of the day and your eyes are focusing on light intensity, not just whether it's there or not. So they can still keep their rhythms at that time of year. But there is a point in the winter where their clocks have not had appropriate input for long enough because it's been dark for so long. And they do seem to stop showing signs of 24-hour cycles if you look at the reindeer. So it looks like at some point they do start free cycling, essentially, and their circadian rhythm start to break down. Wow. They don't seem to have physiological problems associated with that.

I'm not quite sure why, but it looks like they do break down at some point. So it's bad for them to be in the dark. Like, it would be better if they got light occasionally to sort of, like, correct their cycles or get them back on track. Yeah, so I was trying to figure out the answer to that. And I think that the answer is to some extent that it's complicated. So, you know, part of why we have cycles is that it helps us figure out, like, when we should be eating and stuff like that. And part of that, if you're a wild animal, is about when your food is even available. Right.

But if you're in the dark and all the other animals are in the dark, all the dark, all that. the time too, you might not need to have a circadian rhythm because it might, you know, if you're, say you're a fox living in the Arctic Circle, you want to make sure you're awake at the same time as the bunnies. But if it's complete darkness and everybody's free cycling, you don't really need to get up at a certain time because the bunnies could be out there at any time. And so it's, it's not a helpful cue anymore to like have your activities sink to a certain time of day. I was wondering more about the internal stuff, like you mentioned earlier, that if your rhythm gets messed up your risk for diabetes and cancer and stuff. Is the same thing true for reindeer

from when they're free cycling? Yeah, so I don't know the answer for reindeer, but I did try to find the answer to that question. I was able to find some information about blind cave fish. Ooh. So there are fish that live in caves that have closely related ancestors that live outside of caves. Oh, okay. And so you can compare, you know, essentially these like sister species or sibling species and see how they differ. And the species that live in caves don't have shorter lives. And in a lot of cases, they have longer lives than their surface living counterparts. Okay, and then let me tell you about their circadian rhythms. That's the important piece here. So people were trying to figure out if cavefish have circadian rhythms. And they were trying to

figure out, like, okay, in the absence of light, how do you do that? And so one idea they had was that maybe bats that go in and out of the cave are what they're queuing into because when the bats leave where they come back they poop in the water and that poop provides food for a lot of cave fish. So maybe that's what they're sinking to but there was no evidence

that that was actually happening. So it looks like they're not sinking to that. But there could be a lot of similar effects, right? Where things are happening outside the cave and even the microbes in the air or something like that could be affecting you could be sensing indirectly the fact that there's day and night.

outside the cave from inside the cave. Yeah, that's right. But so people have also brought the cave fish into the lab. And when they bring them into the lab and they expose them to normal light cycles, they can develop circadian rhythms. So they still, even though they don't have eyes, they still must have like the cells needed to detect light

and they can develop rhythms. But it looks like various parts of their circadian clock are messed up. So if you look at things from the genetic level, it's kind of messed up. And it looks like they also, for the, the most part, are losing their circadian rhythms in the cave, but that doesn't seem to be shortening their lives. Wow, fascinating. Yeah, which is not what I expected. Like, I spent a long time being like, well, no, what is the cue? They have to have circadian rhythms. And then I

found a review paper that pretty much was like, their rhythms kind of seem to disappear in caves. They're just kind of like moving around whenever and sleeping whenever. And that's okay. And that's okay. We're not judging. Teenagers everywhere are like, see, mom, it's fine for me to stay up until 2 a.m. Right. And their rooms are kind of like messy caves. And I see lots of points of comparison here. All right. What about at the bottom of the ocean where light doesn't filter down? Okay. So this is interesting. So after I had finished the research on caves, my expectation was that animals that live in the deep sea are also going to not really show circadian rhythms. Because they're, you know, they're down in an area where the light isn't

getting to. But I thought, well, you know, maybe there's still some cues like a lot of the food that comes to the deep sea comes from things just sort of like dying and raining down. And I thought maybe there's like a daily pattern to how the food rains down. But this is actually really hard to study. To when the carcass snacks happen. Yeah, well, you know, I pay attention to snacks. Kids, dead bodies are falling. Come on outside. Well, what does it like to be a parent to the bottom of the ocean? I mean, when a whale falls down, it is like buffet for months. The videos are messed up. But so the way that folks tend to study this is, you know, they either take the deep sea animals into the lab.

But if you bring them into the lab, you're often, like, turning on lights to study them. And so now they're in, like, a not natural environment. And, you know, labs in general are not, like, the bottom of the sea. But another way that people study it is they will put, like, essentially mobile labs, they'll lower them down to the bottom of the sea. And then they'll, like, take pictures or videos and try to see if they can, detect cycles and what's happening down there. But another problem there is that they turn on lights often when they do that. Yeah.

And so this stuff is hard to study, but I found a study that did use cameras with lights, and they found that a lot of species didn't show detectable patterns, but it was also hard to get large sample sizes. But they did find that there is a kind of worm that lives in a tube, and there's a pattern to when it sticks its head out of the tube to, like, try to get food. They were looking at different things that were changing. in the environment, and it looks like this behavior is correlated with the tides. So you can still feel the tides at the bottom of the sea, which is amazing.

I didn't realize that. Yeah. Thank you, Moon, see? That's all connected. Yeah. Turns out there is a through line for the whole episode. That's right. I guess spaghettification is kind of interesting.

But I guess, so it's not just the tides, but the tides have different temperatures, so it could be temperature that's queuing this. The tides also can bring food. So maybe it's the food that's queuing the clock. and this information is largely observational. So there's still a lot that we have left to learn, but some indication that tides can be what's impacting timing in the deep sea.

And that's literally everything I know about circadian clocks because this is complicated. All right. So bottom line for us, what do we know about how circadian rhythms work in animals that never see the sun? Sometimes you're poned and you can't create a circadian rhythm because you just don't have the cues.

Other times you can find something that correlates with the light, or sometimes instead of having a circadian rhythm, you have a circotidal rhythm or something, and you're queuing in on some other environmental thing that can help you maintain a rhythm in your life. Well, I thought that answer was supercalifragilistic, but let's hear what our listener says and see if there are follow-up questions. Wow, thanks for answering my question. Never would have thought that deep-sea creatures could sense the tides all the way down there.

That's pretty cool. Hi, Kyle. Could you draw up a quick document with the basic business plan? Just one page as a Google Doc, and send me the link. Thanks. Hey, just finished drawing up that quick one-page business plan for you. Here's the link. But there was no link.

There was no business plan. It's not his fault. I hadn't programmed Kyle to be able to do that yet. My name is Evan Ratliff. I decided to create Kyle, my AI co-founder. After hearing a lot of stuff like this from OpenAI CEO Sam Aldman, there's this betting pool for the first year that there's a one-person billion-dollar company, which would have been like unimaginable without AI and now will happen.

I got to thinking, could I be that one person? I'd made AI agents before for my award-winning podcast, Shell Game. This season on Shell Game, I'm trying to build a real company with a real product run by fake people. Oh, hey, Evan. Good to have you join us. I found some really interesting data on adoption rates for AI. agents in small to medium businesses. Listen to show game on the IHeart radio app or wherever you get your podcasts.

I'm Robert Smith. This is Jacob Goldstein. And we used to host a show called Planet Money. And now we're back making this new podcast called Business History about the best ideas and people and businesses in history. And some of the worst people, horrible ideas and destructive companies in the history of business. Having a genius idea without. A need for it is nothing. It's like not having it at all.

It's a very simple, elegant lesson. Make something people want. First episode, How Southwest Airlines Use Cheap Seats and Free Whiskey to fight its way into the airline business. The most Texas story ever. There's a lot of Mavericks in that story. We're going to have Mavericks on the show.

We're going to have plenty of robber barons. So many robber barons. And you know what? They're not all bad. And we'll talk about some of the classic great moments of famous business geniuses, along with some of the darker moments that often get overlooked.

Like Thomas Edison and the electric chair. Listen to business history on the IHeart Radio app, Apple Podcasts, or wherever you get your podcast. For 25 years, I've explored what it means to heal, not just for myself, but alongside others. I'm Mike Delarocha. This is Sacred Lessons, a space for reflection, growth, and collective healing. What do you tell men that are hurting right now? Everything's gonna be okay on the other side, you know, just push through it. And you know, ironically, the root of the word spirit is breath.

Wow. Which is why one of the most revolutionary acts that we can do as people just breathe. Next to the wound is their gifts. You can't find your gifts unless you go through the wound. That's the hard thing. You think, well, I'm gonna get my guess. I don't want to go through all that. You gotta go through the wounds you're laughing.

Listening to other people's near-death experiences, and it's all they say in conclusion. In conclusion, love is the answer. Listen to Sacred Lessons as part of the Mike Uthura Podcast Network, available on the IHeart Radio app, Apple Podcasts, or wherever you get your podcast. Hi, I'm Dr. Pryonk Wally. And I'm Hurricane DeBolu.

On our new podcast Health Stuff, we demystify your burning health questions. You'll hear us being completely honest about our own health. I'm talking about very serious stuff right now, and you're laughing at me. And you'll hear candidates, advice and personal stories from experts who want to make healthcare more human. Sometimes you're there to listen, to understand, to empathize, maybe to give them an

understanding or a name for what's going on. That helps people a lot, understanding that is not just in their head. We are breaking down the science, talking with experts, and sharing practical health tips you can actually use in your day-to-day life. From when to utilize and avoid artificial light to how to sleep better. Everything you need to know about fiber and how to poop better. How to minimize the effects of jet lag and how to stay hopeful in times of distress. We human beings, all we want is connection. We just want to connect with each other. We want to make health less confusing and maybe even a little fun. Find health stuff on the IHeartRadio app, Apple Podcasts, or wherever you get your podcasts.

We are back to Jupiter, a fascinating planet that could kill us all. Arthur, what do you want to know about Jupiter? Hi, Danube and Kelly. Nice to talk to you guys. I have a rocket thrust issue. I know that we can't escape the gravity of a black hole, no matter how powerful our rocket is. But I don't know the largest mass of a planet we can escape with our current technology. I mean, can an average space rocket lift off from Jupiter, from the sun, from a neutron star? I hope you have some fun answering this. Thanks.

See, Jupiter is just so attractive gravitationally. People can't stop thinking about it. It's beautiful also. All right, so Arthur is wondering about taking off from planets because the more mass of the planet, the stronger the gravity, the harder it is to lift off of. and he wants to know if an average rocket could actually get you off of Jupiter or even more exotic and denser locations. So the first thing I want to know is I can tell from the answer it's going to require math. Did you do these calculations or is there a website that has this information?

There are a lot of websites that have this information, but I never trust them because you can find mistakes on those websites, which is the source of a lot of mistakes in like chat GPT because it just like strips them from the websites. gives you the answer. Sometimes in the wrong context or whatever. So I always double-check these myself. All right. Wow. So what matters for lifting off the surface? You're probably going to think escape velocity. And first I want to say it's not about escape velocity, but then it's going to turn out to be about escape velocity. Physicist. I know. So escape velocity famously is the speed you have to be going so you can escape the gravitational pull of an object. Right. So for example, if I'm standing on the surface of the earth, how fast do I have to throw a baseball street? up so that it just keeps going forever, that its kinetic energy overcomes the potential energy

well that has to climb out of, right? So as you move up away from the earth, you're gaining potential energy that has to come from somewhere, comes from your kinetic energy. If you have enough kinetic energy, then you can go forever, essentially. If your kinetic energy overcomes the potential well, you have to climb. So you have to go fast to escape the earth. But the reason that's not what this is about is that that's not how rockets work, right? Rockets, you don't slingshot them from the Earth in one push. I mean, people are working on that, and it's hilarious. But traditional rockets...

Wait, why is it hilarious and not inspirational? It's just like the grown-up version of a nine-year-old boy's idea for how to get to space. You know, like, let's pull back a really big rubber band, you know? I mean, I knew they're working on centrifuges and it's pretty cool, but it seems like impractical to me also because the G-forces are insane. So I think you could probably launch, like, stuff into space, but not. people. Anyway. That's my sense too. Yeah, you're launching stuff, hardened payloads, not humans. Anyway, that's not how traditional rockets work. If you notice when a rocket takes off,

it's not going super-duper fast. It's very slowly climbing, right? And that's because rockets don't have a single hard push at the beginning where they gain a lot of speed and then gradually lose it as they rise. They have a continual force. They have an engine on them. So rockets only have to go non-zero velocity in order to move up, right? As long as the force from the rocket is greater than the force of gravity from the Earth, it's going to be moving up. Okay. Right?

So it can move up super duper slowly. It could take like a year to take off from the planet. It doesn't matter. It's not about escape velocity. It's about putting enough energy in to overcome the potential energy, the Earth, but it doesn't have to all be up front. So that's why it's sort of not about escape velocity. Okay, but so say you were lifting off at like a foot per second.

that would be much more energetically expensive, wouldn't it? Because you're needing to, like, maintain the mass you're trying to send up as you slowly go up. And if you do it all faster, that's probably more efficient. It's more efficient, yeah. And if you do it all at once just by giving it one big push, then you don't need to bring any propellant with you and you can just accelerate the payload, right? Whereas if you're climbing up at a foot per second, yeah, you've got to bring the rest of the ladder with you, essentially, and you've got to lift that fuel.

So we're definitely going to get there. So what we do need to do is think about how much fuel we have to bring and how we can overcome this energy. And so you have to calculate how much kinetic energy do you need to overcome the potential energy of the Earth. It's not important that it all be at once, and rockets do it gradually. But the way to calculate that is to calculate what they call the delta V, the change in velocity that a rocket can provide. And in the end, this turns out to be very similar to the escape velocity. And it makes sense that it's similar. because they're both connected to essentially how much energy you need to climb out of this gravitational

well. And so on Earth, the escape velocity is about eight kilometers per second. That's how fast you would have to throw a baseball or launch a payload from the surface. But it's also very closely connected. We'll use the rocket equation in a minute to how much fuel you have to bring with you. And that's going to turn out to be the limiting factor of whether you can lift off the planet is, can you practically bring enough fuel to get this much delta V? So on Earth, you need like, eight kilometers per second. And then you go to the rocket equation. The rocket equation says, how much mass do you need to bring so that you can do this? So you can climb out of this gravitational well. Because remember a rocket, what is it doing? It's throwing stuff out the back.

Right? The way it works is it's conserving momentum. Imagine you're like in a rowboat and you have a pile of bricks. You throw the bricks out the back of the rowboat. The bricks go backwards. You go forwards. That's how a rocket works. It's throwing stuff out the back. So you have to have that stuff in the rocket to throw out the back in order to propel it. It's helpful if that stuff also has the energy you can use to push the propellant. It doesn't have to be. You can have those things be uncoupled. But in a chemical rocket, you have fuel, which is both propellant and the source of energy. And the rocket equation tells you what your mass ratio is. So on Earth, for example, you need a delta V of about 10 kilometers per second. That tells you your mass ratio is nine,

which means you need a nine to one fuel to payload mass ratio. That's not great. It's not great. Yeah, if you have like a hundred kilogram person and a thousand kilogram spaceship around them, you need nine times as much mass and fuel to get that thing into orbit. Wow. Yeah. How much worse is it for Jupiter?

And does it scale linearly? It scales exponentially, which is the bad news, right? And so say you're on a super earth, which has the mass of like five to ten times the Earth. Then the escape velocity is like 25 to 30 kilometers per second. Okay, that's not so bad. It's three to four times as much. But the mass ratio is 93. It's 10 times as bad as it is here on Earth.

93 to 1. 93 to 1. So instead of having a 9 to 1 fuel to payload ratio, you have a 93 to 1 fuel to payload ratio. So now, like, your rocket is basically just fuel, right? And that's just for a super earth. Now, go to Jupiter. Jupiter is so massive that its escape velocity is like 40 kilometers per second. And this gives a mass ratio of more than a thousand.

Wow. Right? So you'd need a fuel tank that's a thousand times bigger than your payload. This is probably even an underestimate. But essentially, this is impossible for chemistry. The chemical rockets cannot achieve this. And if you went to the sun, right, then the escape velocity from the sun is 400 kilometers per second. And so now the mass ratios are just astronomical.

From a neutron star, the escape velocity is four-tenths the speed of light. And so I couldn't even get my calculator to give me a number on this one, which is so big. And so the bottom line is that chemical rockets, where you have this fuel and you're slowly climbing out of the gravitational well, they work pretty well if the escape velocity is low because the mass ratio is pretty small. You can afford nine to one, which sounded bad already to you, right? But on a bigger planet, like a super earth, it's pretty hard to use. And on Jupiter or the sun or neutron star, it's definitely not practical.

So what about like a Project Orion-style propulsion system? So if you were exploding nuclear bombs out the back of your rocket to send you up, could you get off of Jupiter? Yeah, you could. This is limited to chemical rockets, right? And you can have other strategies. You could build a space elevator, right? you could have nuclear propulsion, absolutely. And especially if you're launching the nuclear weapons behind the rocket somehow

so that they don't have to come along with the rocket, then you can escape this trap of having to bring all of your propellant with you. Yeah, or if you have like a light sail with a laser behind it, you can use that to lift off of a planet. Or you could just build your thing in space anyway. Like, why are you building it on the surface of Jupiter? That doesn't really make sense unless that's where your super villain hideout is. In which case I have to wonder, Jupiter doesn't get a whole lot of light.

I wonder how your circadian rhythms are going in your supervillain layer. One, you better hope that Brad isn't sending the Earth careening into your supervillain layer on Jupiter. Oh, maybe he's saving us, right? Maybe he's using the Earth. That doesn't really work, does it? Using the Earth to crush somebody else's supervillain layer? Yeah. Not a great plan, Brad.

I'm not paying you to write that plot, Daniel. So, yeah, chemical rockets work essentially. only on smaller planets. On bigger planets, you need other technologies. But those technologies are not impossible. So I think if we did evolve on Jupiter or on the surface of a neutron star, technically it's still possible to get off of those, but not with rockets. All right. Let's see if Arthur has any follow-up questions and maybe he'll tell us what his supervillain plan is. Thanks guys for the kind answer to my question. I knew that lifting off from a bigger planet would be hard, but I didn't knew it would be almost impossible, at least for chemical rockets,

as you explained. I think that this either puts a big as a risk on plans for space exploration, since the range of celestial bodies we could visit would be very limited, or either forces research for more efficient technologies, as you mentioned. All I have to say about supervillans is that they love rockets these days, so I do not doubt they have plans for this massive madness. Thanks a lot. All right. Thank you, everybody, for sending in your questions. Remember, you can write to us to questions at Daniel and Kelly.org and send us your thoughts about the universe, your musings,

your wonderings, your philosophical meanderings. Please, we'd love to hear from you. Can't wait to hear from you. Thanks, everybody. Stay curious. Daniel and Kelly's Extraordinary Universe is produced by IHeart Radio. We would love to hear from you. We really would. We want to know what questions you have about this extraordinary universe. We want to know your thoughts on recent shows, suggestions

for future shows. If you contact us, we will get back to you. We really mean it. We answer every message. Email us at Questions at Danielandkelly.org. Or you can find us on social media. We have accounts on X, Instagram, Blue Sky, and on all

of those platforms, you can find us at D and K Universe. Don't be shy. Write to us. I know he has a reputation, but it's going to catch up to him. Gabe Ortiz is a cop. His brother Larry, a mystery Gabe didn't want to solve until it was too late. He was the head of this gang.

You're going to push that line for the cause. Took us under his wing and showed us the game, as they call it. When Larry's killed, Gabe must untangle a dangerous past, one that could destroy everything he thought he knew. Listen to the Brothers Ortiz on the IHeartRadio app, Apple Podcasts, or wherever you get your podcasts. Hi, Kyle. Could you draw up a quick document with the basic business plan? Just one page as a Google Doc. And send me the link. Thanks. Hey, just finished drawing up that quick one page business plan for you. Here's the link. But there was no link. There was no business plan. I hadn't programmed Kyle to be able to do that yet.

I'm Evan Ratliff here with a story of entrepreneurship in the AI age. Listen as I attempt to build a real startup run by figure. people check out the second season of my podcast shell game on the iHeart radio app or wherever you get your podcasts what are the cycles fathers passed down that sons are left to heal what if being a man wasn't about holding it all together but learning how to let go this is a space where men speak truth and find the power to heal and transform i'm mike delarocha welcome to sacred lessons My Heart Radio app, Apple Podcasts, or wherever you get your podcasts. The show was ahead of its time to represent a black family in ways the television hadn't shown before. Exactly.

It's Telma Hopkins, also known as Aunt Rachel. And I'm Kelly Williams or Laura Winslow. On our podcast, welcome to the family with Telma and Kelly. We're re-watching every episode of Family Matters. We'll share behind-the-scenes stories about making the show. Yeah, we'll even bring in some special guests to spill some tea. Listen to Welcome to the Family with Telma and Kelly on the IHeart Radio app, Apple Podcasts, or wherever you get your podcasts. This is an IHeart podcast, guaranteed human.