How GPS Works

Summary

Podcast Summary: Stuff You Should Know – Episode: How GPS Works

Release Date: February 27, 2025 | Host/Author: iHeartPodcasts

In the February 27, 2025 episode of "Stuff You Should Know", Josh Clark and Chuck Bryant delve into the intricate workings of the Global Positioning System (GPS). This comprehensive episode not only explores the technical foundations of GPS but also honors the legacy of Marshall Brain, founder of HowStuffWorks, whose contributions significantly shaped the podcasting landscape.

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1. Introduction and Tribute to Marshall Brain (00:30 - 04:44)

The episode opens with Josh Clark and Chuck Bryant paying heartfelt tribute to Marshall Brain, the visionary behind HowStuffWorks.com, who passed away in November at the age of 63. Marshall's mission was to demystify complex topics for everyday understanding, laying the groundwork for the hosts' own endeavors.

Josh Clark (02:34): "He had a very pure goal, which was to make complex things understandable and relatable to everyday people."

Marshall's influence is palpable as Chuck reflects on how Marshall's work led him and Josh to podcasting, ensuring the continuation of making intricate subjects accessible.

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2. The Birth of GPS (04:36 - 10:36)

As a tribute, the hosts revisit one of Marshall Brain's original articles on GPS. The discussion begins with a simple definition:

Josh Clark (04:47): "GPS tells you where you are. The end."

They unpack this seemingly straightforward statement by exploring the origins and evolution of GPS. GPS is identified as a Global Navigation Satellite System (GNSS), with the U.S. owned and operated by the Space Force. The term "GPS" has become synonymous with GNSS globally, much like "Kleenex" is for tissues.

The historical context traces back to Dr. Ivan Getting, an American physicist who envisioned using radio signals to determine precise Earth locations. Despite initial skepticism, this vision materialized post the launch of Sputnik by the Soviets, which catalyzed the development of GPS as a means to track satellites.

Chuck Bryant (08:29): "They launched Sputnik, and it took us by surprise. But Dr. Getting's theory was able to be put into use."

The NavStar program was established in 1973, leading to the operational GPS system by 1995. Initially a military project, GPS was later made available for civilian use, a decision influenced by tragedies like the downing of Korean Airlines Flight 007 in 1983.

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3. Components of GPS (10:36 - 17:48)

GPS operates through three main components:

1. Satellites: Orbiting at approximately 11,000 miles above Earth, these satellites continuously transmit microwave signals. At least four satellites are visible from any location on Earth at any given time, enabling precise location tracking.

   Chuck Bryant (06:54): "There are more than 30 satellites orbiting the Earth at any given time."

2. Control Systems: Ground-based stations, managed by the Space Force, monitor and manage the satellite constellation, ensuring synchronization and accurate positioning.

   Josh Clark (07:42): "The Space Force runs GPS, constantly tracking and monitoring the satellites."

3. Receivers: Devices like smartphones and GPS units receive signals from satellites to determine the user's location through trilateration.

   Chuck Bryant (16:27): "These microwaves contain critical information like the satellite's location and precise timing."

Marshall Brain's methodologies shine through as the hosts emphasize the blend of engineering and science that makes GPS reliable.

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4. How GPS Determines Location (17:48 - 30:11)

The core mechanism of GPS lies in trilateration, not to be confused with triangulation. Trilateration involves calculating distances from multiple satellites to pinpoint an exact location on Earth.

Josh humorously illustrates trilateration with a fictional scenario:

Josh Clark (24:47): "If you ask someone where you are, like 'You're 625 miles from Boise,' it doesn't help much without additional data."

By obtaining distances from at least three satellites, GPS receivers can determine a precise 3D location (latitude, longitude, and altitude). The process relies heavily on the accurate timing provided by atomic clocks onboard satellites.

Chuck Bryant (22:23): "One of the cool parts about that is it's going to tell you like, yeah, it's coming from this satellite. Here's my pseudo random code."

The use of pseudo-random codes ensures that signals from different satellites don't interfere, allowing receivers to distinguish and process multiple signals simultaneously.

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5. Enhancements to GPS Accuracy (30:11 - 36:02)

While GPS is highly accurate, external factors like tall buildings, weather, and dense foliage can affect signal strength and precision. To counteract these discrepancies, Differential GPS (DGPS) is employed. DGPS uses fixed ground stations to monitor signal distortions and provide correction data to receivers, enhancing overall accuracy.

Josh Clark (20:06): "Differential GPS has these known points that help adjust and correct discrepancies in the signals received."

Additionally, advancements like dual-band receivers that utilize both L1 and the newer L5 frequencies are paving the way for even greater accuracy, potentially down to 30 centimeters under optimal conditions.

Chuck Bryant (37:36): "When you put L1 and L5 together, it gets pretty good."

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6. Applications of GPS (36:02 - 40:48)

GPS technology is integral to numerous industries and everyday applications:

• Navigation: From personal smartphones to commercial aviation, GPS guides millions daily.

• Agriculture: Precision farming relies on GPS for tasks like soil moisture tracking and automated harvesting.

• Construction: GPS-enabled machinery and digital blueprints streamline building processes, reducing costs and time.

• Environmental Monitoring: Tracking glacier movements and wildlife migration patterns provides valuable ecological data.

• Automotive: Self-driving cars depend on GPS for accurate navigation and autonomous operations.

Chuck Bryant (39:00): "Contractors use GPS coordinates for things like electrical outlets, cutting down on construction costs and time dramatically."

The economic impact is substantial, with the GPS industry generating $94 billion in 2022 and projected to approach $300 billion within five years.

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7. Vulnerabilities and Security Concerns (40:48 - 48:38)

Despite its ubiquity, GPS is not invulnerable. Jamming and spoofing pose significant threats:

• Jamming: Disrupts GPS signals, causing receivers to lose accuracy or fail entirely. In 2022 alone, over 70,000 flights experienced jamming incidents in three regions.

• Spoofing: Involves sending misleading signals to receivers, potentially causing navigational errors. An example includes Iran in 2019 spoofing a British cargo ship's GPS, leading to its capture.

These vulnerabilities highlight the critical need for robust security measures to protect both civilian and military GPS applications.

Josh Clark (41:54): "Countries do that all the time, but any schmo with $300 can jam someone's GPS."

The lack of a backup system exacerbates these risks, making GPS-dependent industries and services susceptible to disruptions.

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8. Future of GPS Technology (48:38 - 51:17)

Looking ahead, continuous improvements are essential to maintain and enhance GPS functionality:

• Satellite Upgrades: Incorporating more L5 satellites to support dual-frequency receivers, enhancing accuracy and reliability.

• Advanced Receivers: Development of more sophisticated GPS antennas in smartphones and other devices to better withstand jamming and spoofing.

• Global Cooperation: Efforts to develop alternative GNSS systems (like those from China, Russia, and the EU) to provide redundancy and resilience.

The episode underscores the importance of evolving GPS technology to meet growing demands and counter emerging threats.

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Conclusion and Final Thoughts (51:17 - End)

Josh and Chuck conclude the episode by reflecting on the intricate balance between GPS's benefits and its vulnerabilities. They reiterate the system's profound impact on modern life while acknowledging the ongoing challenges in safeguarding its integrity.

Josh Clark (48:38): "It's getting better, though. I mean, it's getting..."

The episode serves as both an informative guide to understanding GPS and a tribute to the innovators like Marshall Brain who have made such knowledge accessible to the masses.

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Notable Quotes:

• Josh Clark (04:47): "GPS tells you where you are. The end."
• Chuck Bryant (06:54): "There are more than 30 satellites orbiting the Earth at any given time."
• Josh Clark (16:27): "These microwaves contain critical information like the satellite's location and precise timing."
• Chuck Bryant (37:36): "When you put L1 and L5 together, it gets pretty good."
• Josh Clark (41:54): "Countries do that all the time, but any schmo with $300 can jam someone's GPS."
• Josh Clark (48:38): "It's getting better, though."

---

This episode of "Stuff You Should Know" provides a thorough exploration of GPS, blending technical explanations with entertaining anecdotes and personal reflections. Whether you're a tech enthusiast or simply curious about how your smartphone accurately maps your location, Josh and Chuck offer valuable insights into the marvel that is GPS.

Transcript

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[Questlove]

Hey, everybody, what's up? This is questlove, and every year we do special programming in February for Black History Month. Now, it's especially important this year as we gear up for some new conversations. So the team and I compiled some clips from the show that are worth revisiting in part one of the celebration of Black History Month. We're listening back to Moments with Chris Rock, Solange Prodigy, Ben Vereen, Jennifer Lewis, Angela Rye, and Gina Yashore. Listen to Questlove supreme on the iHeartRadio app, Apple Podcasts, or wherever you get your podcast.

[Josh Clark]

Welcome to Stuff youf Should Know, a production of iHeartRadio.

[Chuck Bryant]

Hey, and welcome to the podcast. I'm Josh. And there's Chuck. And Jerry's here, too. Jerry's at a cabin in the woods even. And this is stuff you should know. Podcasting from the future.

[Josh Clark]

That's right. And we are going to take a couple of minutes here at the head of the show to pay tribute to housetopworks.com founder Marshall Brain, who passed away last November at the age of 63.

[Chuck Bryant]

Yeah, he is the guy who started it all. And it's really hard to understate the impact that that guy had on our lives.

[Josh Clark]

Yeah, 100%, just about Marshall. He was an electrical engineer, had a Bachelor of Science. He was a longtime professor at NC State. And in 1998, he founded as a hobby, howstuffworks.com because he wanted to. He had a very pure goal, which was to make complex things understandable and relatable to everyday people. And that is, you know, that's what we still do. We were hired as writers there. I never met Marshall personally. I think I saw him come through the office a couple of times early on, but I never had the pleasure of actually sitting down with a guy.

[Chuck Bryant]

I met him a couple of times. He was a good guy. I think some of his first articles, I think the first one might have Been like how air conditioning works.

[Josh Clark]

Yeah.

[Chuck Bryant]

Remember Scooby Doo? We did an episode on Scooby Doo based on one of his articles.

[Josh Clark]

Was that Marshall?

[Chuck Bryant]

Yeah, totally.

[Josh Clark]

Oh, interesting.

[Chuck Bryant]

But yeah, he was a very good guy. And without him, I can tell you, I would not be podcasting. And if I were, it probably wouldn't be a very good podcast. Cause you and I would have never met. Yumi and I would have never met. Like, the fact that Marshall came along and founded How Stuff Works set my destiny in a lot of ways. So I'm really grateful to him for that.

[Josh Clark]

Yeah, for both of us. He was also an author. One of his books is called the Doomsday Book. The Science Behind Humanity's Greatest Threats. Something that Josh has particular interest in.

[Chuck Bryant]

Yeah, for sure. Yeah. He's a transhumanist. Down with Nick Bostrom and all those guys.

[Josh Clark]

Yeah. So Marshall was also a TV host. He eventually was the director of NC State's Engineering Opportunities Program, which helped mentor aspiring inventors. And Marshall was survived by his wife, Leanne, his four kids, David, Irina, Johnny and Ian, and their dog, Summer. And it was just really sad to hear the news because like you said, Marshall, if it wasn't for him, we wouldn't be here now. And we'd like to think we're still carrying on his tradition of making complex things accessible.

[Chuck Bryant]

I like to think that too.

[Josh Clark]

Yeah.

[Chuck Bryant]

So here's to you, Marshall. Rest in peace. And as tribute, we chose an article, one of the few ones that we hadn't recorded that, that Marshall wrote originally on gps. And this is like bread and butter, Marshall brain stuff. There's engineering, there's science, there's some more engineering. There's figuring things out with circles and diameters and stuff like that. Like straight up Marshall stuff.

[Josh Clark]

Yeah, Classic Marshall. Classic how stuff works. And even though our show has kind of grown and morphed, it's fun to go back and do these every now and then.

[Chuck Bryant]

Yep, for sure. So let's get started, shall we?

[Josh Clark]

All right. GPS tells you where you are. The end.

[Chuck Bryant]

There you go. That's word for word. Marshall's article.

[Josh Clark]

Yeah, it actually sounds intimidating, but it's really not at all. It's a pretty simple process, believe it or not.

[Chuck Bryant]

Yeah, surprisingly.

[Josh Clark]

But what it is, overall, GPS is a. As Marshall wrote a space based radio navigation system that technically GPS is the one that the US government owns. If you live in another country. It's not called gps, it's called what, a gnss?

[Chuck Bryant]

Yeah. Global Navigation Satellite system is the generic term. And GPS has Become like the Kleenex of global navigation satellite systems. Like it's the proprietary eponym.

[Josh Clark]

Yeah, exactly. But, you know, that's what the system is that tells you where you are when you take out your little smartphone and say, where in the world am I? Or how in the world do I get somewhere? If you want to get somewhere, they got to know where you are at that moment. And that's why you can do that 24 7.

[Chuck Bryant]

Yeah. And GPS is owned and operated by the American government and it's paid for by the American taxpayers, but it's used worldwide. I think out of 8point something billion people on the planet today, 6 billion of them use GPS every day. So it's America's gift, I think, is what I'm trying to say. Because if anything, that's what America is known for. It's like creating things and giving it away to the rest of the world for free.

[Josh Clark]

Yeah, well, we'll see what happens with that. You never know. But right now, that's the current situation. They do this with satellites at least 24. Usually there's more than 30. And wherever you are on Earth, if you had super, super long vision, you could look up and see four of these bad boys with your eyeballs. Because you gotta have those four to tell you where you are for sure.

[Chuck Bryant]

Technically you just need three, but let's not get into that right now. Okay, so the satellites are up in medium Earth orbit, about 11,000 miles above Earth. They circle it constantly. They're not geostationary, so they circle the Earth and they rise and set, I guess every 12 hours, so twice a day. They're like the tides, basically. And the GPS satellites are just one component. There's three components. There's a satellite component, there's the control component, which is on the ground. The Space Force runs gps. So they're constantly tracking, monitoring, telling satellites what to do, like really bossing them around. And then the third component is you, the person using gps, or more technically, your receiver, that is telling you where you are in the world.

[Josh Clark]

Yeah, that's the important part, because I've tried. I've gone out there without a phone and just shouted up, where am I? Nothing happens.

[Chuck Bryant]

They're like, get a phone.

[Josh Clark]

One of the cool things about GPS is this was kind of roughly figured out a long time before we even had satellites. There was a doctor, Dr. Ivan Getting, who was a physicist, an American, who basically said, hey, you know what? You could find out someone's 3D coordinates if you use radio signals and just calculated the time it takes for those signals from different sources to reach a single point on Earth. And that's gps, basically.

[Chuck Bryant]

Yeah. And the people around getting especially his greatest critics were like, oh, yeah, yeah, how are you going to do that? There's nothing up in space, you jerk. How are you going to do it?

[Josh Clark]

Exactly.

[Chuck Bryant]

And he said, just wait. And they sat around and they waited. I don't know how long they waited for a while, and they finally went home. And then a couple years after that, the Soviets came to the rescue. In a certain weird way, they launched Sputnik. And in America, in the United States, it was not a happy time. They called it the Sputnik crisis because basically at the time, we thought the Soviets were just like some backwater backwards country. And all of a sudden, they were the first ones to launch a satellite into space. And it took us by surprise. But Dr. Gedding's theory was able to be put into use because American scientists figured out that you could track Sputnik because its radio signals. I don't know quite how to put it. Let's say they engaged in the Doppler effect. They dabbled in Doppler so that when the satellite was moving away from you, the frequency that reached you here on Earth was different than the frequency when the satellite was moving toward you or when the satellite was just stationed above you. So they figured out that you can track satellites based on these radio signals. And that gave the initial rise to gps, which is you need to track the satellites to know where they are, because that is an essential piece of information for gps. And that kind of led to people saying, like, okay, let's get getting's idea off the ground. Literally.

[Josh Clark]

Yeah, literally off the ground and into space. Sputnik was 10-57-57. And a couple of years later, we said, oh, yeah, we'll see your Sputnik and we'll raise it five satellites. Or I guess raise it for. For a total of five satellites.

[Chuck Bryant]

Sure. All ACEs.

[Josh Clark]

That's right. And this was 1960. I'm sorry, in 1967, they had really precise clocks on board these satellites. And then just five years, six years after that, in 73, NavStar was formed. And that is the system, the program that, you know, that is gps, basically. And then we said, all right, now it's just going to take us about 20 years to figure all this out.

[Chuck Bryant]

Yeah, 1995, the whole thing was finally operational. They just kept shooting up satellites and tinkering with it and get it going. And I wish we would have kept the name NavStar. I think it's a little cooler than GPS, but I don't know, maybe it sounds a little more hostile or assertive. So GPS is probably okay.

[Josh Clark]

You want to talk about assertive? What about Space Force?

[Chuck Bryant]

Space Force is. I don't know what. Space Force? Is that the name?

[Josh Clark]

It sounds like a movie.

[Chuck Bryant]

It does.

[Josh Clark]

Like a Mel Brooks movie.

[Chuck Bryant]

It does, but. But. So we called it gps, and there were two versions that they released at the same time. One was L1. That bandwidth was used for civilian purposes. Everything from. Well, just. If you weren't in the military, let's say you used L1. If you were in the military, you used L2. It's much more precise out of the gate. But the entire reason that this went from what I think was originally a military project intended just for use by the military to one where everybody who had a GPS receiver could use it for free was actually based on a tragedy that occurred in 19, I think, 83 with Korean Airlines Flight 007.

[Josh Clark]

Yeah, that was a flight intended to go from New York to Seoul. To get there, they were flying over Alaska, and still today, we don't really know why, but it veered off course about 200 miles into Soviet airspace. This was not a great area of Soviet airspace to be near because it was near some secret military installations. And so they scrambled a couple of fighter jets, Soviets did MIGs, I reckon, and they tried to contact the plane, could not get in touch, and then downed the plane with a missile and killed everybody. 269 people. I remember this. I was 12. Oh, yeah? Yeah. I mean, you know, of course, I didn't understand something like that fully at 12, but I remember it being, you know, all across the news.

[Chuck Bryant]

Well, having been raised in the United states and being 12 in 1983 during the cold War, I'll bet you were so mad at the Rusky commies for doing that.

[Josh Clark]

Oh, man. Oh, man. There was probably a song on FM radio that, you know, encapsulated this.

[Chuck Bryant]

Oh, I'm sure.

[Josh Clark]

Like that a DJ made, you know, not a real song.

[Chuck Bryant]

Right, right.

[Josh Clark]

There were so many. It used to be such a thing.

[Chuck Bryant]

Yeah, it was. Weirdly, it was a thing. But I'll bet it was Survivor that sang the song.

[Josh Clark]

Yeah, probably. What I don't fully get now, what I do get is that, you know, airplanes and airlines have GPS on their airplanes, so they don't do this now. But why did that, like, broaden it to the public at large? Like, couldn't they have just said, all right, it's for the military and for the faa.

[Chuck Bryant]

I don't know. Maybe they just thought that there were other potential tragedies that they couldn't foresee that could be.

[Josh Clark]

Gotcha.

[Chuck Bryant]

I don't know. I don't know. If there's one thing that I'm not, it's in Ronald Reagan's head. I just don't know.

[Josh Clark]

So we have one GPS system, which is kind of a problem. We don't have a backup yet, which. We'll talk a little bit about that more later. But there is more than one gps because it's not like China and Russia are like, hey, we'll just use your GPS when we want to bomb something.

[Chuck Bryant]

When we want to shoot a missile at you.

[Josh Clark]

Yeah, exactly. So China and Russia and the EU all have their own gps, and I think they all have backups even, and we don't.

[Chuck Bryant]

Right. It just takes too many floppies to back up our gps. So we're just going without right now.

[Josh Clark]

Yeah.

[Chuck Bryant]

You want to take a break?

[Josh Clark]

Yeah, let's take a break. I think it's a fantastic setup.

[Chuck Bryant]

Okay. And when we come back, we're going to really wing it by trying to explain how GPS works.

[Will]

Hey, Will, do you ever get overwhelmed by how much science happens these days?

[Mango]

Constantly. I'm like, ah, there's so much science, I can't keep track of it all.

[Will]

Then it's a good thing. Our podcast, Part Time Genius is counting down the 25 greatest science ideas from the past 25 years.

[Mango]

That's right, Mango. We're talking animals in a paper called.

[Will]

Quote, chickens prefer beautiful humans.

[Chuck Bryant]

This was actually the title of the paper.

[Will]

They all discovered that, much like humans, chickens are attracted to symmetrical faces.

[Chuck Bryant]

Got it.

[Will]

We're talking medical miracles.

[Mango]

He's an endocrinologist who found a way to stimulate insulin producing cells using. Wait for it. The saliva of a Gila monster.

[Will]

There's no way to make that not sound crazy.

[Mango]

We even talked to some of the experts behind these breakthroughs. It's a week full of fact packed stories you won't want to miss. So listen to the Part Time Genius countdown of the 25 greatest science ideas of the past 25 years, starting Monday, March 3rd on the iHeartRadio app, Apple Podcasts, or wherever you get your podcast.

[Josh Clark]

All right, so if you want to geolocate something or somebody, you're going to need and you're on Earth, you know, you can just use longitude and latitude and that'll do a pretty good job.

[Chuck Bryant]

Sure.

[Josh Clark]

GPS is like, hey, what if you want to find out where you are relative to sea level. We can do that and you can't. Longitude and latitude. Yeah, and GPS does that with microwaves. They decided not to use radio waves for reasons we'll talk about, but they use microwaves sent down to Earth.

[Chuck Bryant]

They do. And so these microwaves, I've seen both, Chuck. I've seen that they're constantly beaming transmissions, like, basically uninterrupted from the satellites, or that they do it, like on a repeating pattern. Regardless, however this information arrives, it contains a few really important pieces of information. And one thing we should point out, apparently there's a misunderstanding that a lot of people think when you open up, like your location services or whatever on your phone, your GPS antenna ping satellites. That's not the case. It passively listens for gps. The four GPS satellites broadcasting constantly or intermittently, and it picks them up. Right. And so the information it gets is the time. And this is a really important component. And we've talked before about atomic clocks and just how ridiculously precise they are. And on a GPS satellite, there's multiple atomic clocks that are keeping time together and to make sure that they stay synchronized. And then the satellite sends its own location. Apparently they figure out their location using celestial landmarks like quasars. So the satellite knows where it is at all times. So it can tell you or your GPS receiver. And then there's a satellite ID that says I'm me. And that is good enough.

[Josh Clark]

That's right. And that is in the form of a pseudo random code. And one of the cool parts about that is it's going to tell you like, yeah, it's coming from this satellite. Here's my pseudo random code. But it also uses a slightly differently altered frequency so the frequencies don't jam one another. So all these satellites, because the frequencies are just slightly varied, can all talk to each other. Because you don't want satellites up there jamming each other.

[Chuck Bryant]

No, but they can also talk to you, too, virtually at the same time, if not at the same time. Because don't forget, you're getting information from four different satellites to figure out where you are. So you don't want to get one from one, wait a couple minutes, get one from the other. You want them all to be coming in basically at the same time. And by slightly altering their frequencies, they can all arrive.

[Josh Clark]

Right. And this is one final bit of key, key information here. All these satellites, great, they're beaming microwaves down. Fine. If we didn't know how fast those microwaves traveled, then none of that would do us any good. We have to know exactly how fast that stuff travels in order to measure a distance. And in this case, we know that electromagnetic waves, microwaves, travel at the speed of light, 186,282 miles per second.

[Chuck Bryant]

Right. So now they have all the basic information. I think this is why you were saying at the outset. This is actually kind of a simple setup. GPS is if you take. So if that satellite sends you an information piece of, like, a signal, and it says, I sent this exactly at 1:45pm and it arrives at 1:45pm in one second, and you know that microwaves travel at the speed of light, you can use that information to calculate the distance between you and the satellite. Okay. When you know that the satellite is located here in space, and then you figure out your distance from the satellite, you start to have your first piece of information about where you are. Because now you know where you are relative to one satellite. That's not enough information to tell you where you are on Earth, but it's a really good start.

[Josh Clark]

That's right. And you might be thinking, like, yeah, but what about stuff getting in the way? Like, if this stuff is supposed to be exact, then what about a tall building? Or what about weather and space that can throw all this off, Right, guys? And that's true, but they have a very pretty brilliant workaround for that. One method is called differential gps. And they have these antenna on Earth that are locked in. They're stationary. They're not going anywhere. We know exactly where they are. They're called known points for that reason. And since we know exactly where those are, they're receiving these transmissions from gps, and so they can calculate whether or not the location is off and that, you know, if this thing is locked in place. But the calculation coming from the GPS is off by a little bit. Hey, it must have gone through some thick shrubbery or bounced off a building or something. But either way, we're locked in place. So we know exactly what that should be, and thus we'll know what that discrepancy is, and we can account for that.

[Chuck Bryant]

Right? So once that known point has that discrepancy, it sends that out, that information out to all the GPS receivers in the area so they can use it to adjust their own GPS readings that they're getting from those satellites that were slightly off, but they didn't have any way to remedy it. Now they do, because the known point is like, hey, sort of like B is off by like 10 nanoseconds. Don't tell it. But, yeah, I just wanted to let you know.

[Josh Clark]

Yeah. And hey, listen, I won't tell everybody. I'll just adjust it on my end and they'll never know that you screwed up.

[Chuck Bryant]

Right. And also, there's something in your teeth.

[Josh Clark]

Right? Oh, it's kale.

[Chuck Bryant]

Kale is so gross.

[Josh Clark]

You don't like kale?

[Chuck Bryant]

I can't. I have to choke it down. And gross is the wrong word. It's just too harsh.

[Josh Clark]

Yeah, yeah. Too much kale. Like a salad with only kale. Or like, God forbid you eat a bag of kale chips. Like, that's just.

[Chuck Bryant]

You would die. You wouldn't be able to breathe any longer.

[Josh Clark]

It's too much at once.

[Chuck Bryant]

Yes.

[Josh Clark]

Oh, boy. All right, so now we get to trilateration. Take it away, friend.

[Chuck Bryant]

Oh, no. You're the trilateration expert. Between us, let's tell everybody what happened.

[Josh Clark]

Well, first of all, let me explain that trilateration is not the same as triangulation, because we're not talking about ankles. We're talking about distance. And somewhere in there is the key of where I was screwing up. Because you had sent me this in a very elegant, sort of simple to explain way.

[Chuck Bryant]

Hey, this is Marshall, okay?

[Josh Clark]

A la Marshall Brain. It was explained about, you know, like a Venn diagram. Three circles overlapping, and then the point where they overlap is where you are. We'll explain that more thoroughly. But I was just drawing three random circles, and I'm like, three random circles don't always intersect at a point.

[Chuck Bryant]

Right.

[Josh Clark]

Like, they might overlap in an area. And so the center of that area maybe is what we're talking about. But then I realized you can't just draw three random circles and expect them to have a tangent point because they don't always. Right. In the case of gps, I guess it's just a very exact measurement from one place to another. And in that case, they will intersect.

[Chuck Bryant]

Right. Okay. Okay. So I think you should also tell everybody that when you sent me a picture of your three circles with the part where they overlap, they all overlap. You would put a point in there and wrote bingo with an exclamation point. You're like, case, close.

[Josh Clark]

I thought I really figured out something here.

[Chuck Bryant]

I think you may have discovered something else that we're not aware of yet. So I don't think someone will tell us, just put it to this. No, I think, like, you might have just invented, like, a new way of calculating things.

[Josh Clark]

No, I'm sure there's a name for it. Some science person's gonna say, oh, Chuck, that's just blank.

[Chuck Bryant]

Oh, I wish they would, because I don't know either. But like, hats off to you because, man, I can't tell you how many circles I guess you probably drew just trying to get this to work. And I don't blame you. I. I was smart and was like, there's madness there. I'm just going to try to understand this as best I can. I'm not going to try it myself.

[Josh Clark]

I got a freaking compass at one point because you were like, it's because the circles are willy nilly. And I was like, okay, I'll draw them perfect.

[Chuck Bryant]

Okay, so, well, let's talk about trilateration, because in theory, I guess it's very simple. And the way that Marshall described it was, let's say you're lost, you're in the United States, and you ask somebody where you are, and that person says, you are 625 miles from Boise, Idaho.

[Josh Clark]

And you say, thanks a lot. That doesn't tell me much.

[Chuck Bryant]

Right. You actually push them down as they're walking away. Yeah, but after you get away, you're chased by the police, but you make it down an alley and hide behind some garbage cans as they pass by. You have a good idea, you go buy a map and you spread out your map. Maybe you buy a compass as well, a la Chuck, and you draw a circle around Boise, Idaho, using Boise as the center point. That is 625 miles in diameter. Or at least represents that by scale, right?

[Josh Clark]

Yeah.

[Chuck Bryant]

And you're like, okay, I am somewhere on this circle that has a diameter of 625 miles around Boise. Kind of helpful. It's a little bit narrowed it down, but I need more information. So you go find somebody else and you say, hey, do you know where I am?

[Josh Clark]

Yeah. Is this where I could come in?

[Chuck Bryant]

Yeah, I was hoping so.

[Josh Clark]

Yeah. Hey, well, I'm not going to tell you that, but how about this? You're 690 miles from Minneapolis.

[Chuck Bryant]

Okay. So that's great. At least they didn't repeat the Boise thing. Right. Because if they said that, you'd just be like, man, that didn't help at all. But now you know where you are from Minneapolis, and you can do the same thing with Minneapolis. Using that as the center point of a circle, you draw one, a circle with a radius of 690 miles around Minneapolis. Now you're really close because what you'll find is the circle around Boise and the circle around Minneapolis. They overlap, right?

[Josh Clark]

Yeah. You get a little football in the middle.

[Chuck Bryant]

Yeah, like a Venn diagram. And if you look at a Venn diagram, where those two circles overlap, there's two points where they intersect. Right. Where they cross each other, those lines cross each other. And because you are 625 miles from Boise and 690 miles from Minneapolis, you are somewhere where those two circles overlap with those two points. One of those is right. The other is off by hundreds of miles. So you still need to narrow it down.

[Josh Clark]

Right. So you're like, is there one more wiseacre in this town who will tell me by not telling me where I am? Where I am?

[Chuck Bryant]

Right.

[Josh Clark]

And so you go into this final. The only other gas station in town, and you say, guys, someone told me I was 625 from Boise. Didn't help much. Someone else said, 690 from Minneapolis, please just tell me where I am. They said, oh, oh, you're 650 miles from Tucson.

[Chuck Bryant]

Val, do you just trash the place at this point?

[Josh Clark]

Yeah, you just lay waste. You find the nearest broom, and you just start knocking everything off the shelves.

[Chuck Bryant]

That's awesome. My collector beer steins.

[Josh Clark]

All right, so now you got three circles, though. And this is where I got super tripped up, because I was like, oh, cool, let me draw this out. And I drew it out, and I was like, these don't intersect at a common point.

[Chuck Bryant]

Right.

[Josh Clark]

But if you're using exact GPS calculations, distance from a satellite, or in this case, points on a map, then you know exactly where you are, because it's gonna intersect at only one place, at three points.

[Chuck Bryant]

Yeah. All three circles will overlap with one another, so they intersect at two points. Each circle intersects with the other at two points, but all three of them will only intersect at one single point. And you have just trilaterated your position. You now you know where you are. And Marshall said, this is Denver, by the way. That's where you are is Denver. Because I think if we hadn't have included that, some people would have been really upset.

[Josh Clark]

Yeah, but you knew you're in Denver because you can't catch your breath and it smells like weed everywhere.

[Chuck Bryant]

That's right. And now you have to figure out what to do even though you're dead.

[Josh Clark]

Yeah. And liberals and conservatives are smashed together, and everyone's like, what kind of state is this?

[Chuck Bryant]

It is. It's crazy like that, isn't it?

[Josh Clark]

Yeah. I love Colorado. I think it's interesting that way.

[Chuck Bryant]

It's like all of the shows we've done in Denver. It's like a wedding, like, split down the middle, the people on one half of the room all have guns out. The other half are all playing hacky sack, right? It's an interesting place.

[Josh Clark]

And one guy goes, hey, you ever try to shoot a hacky sack at midair?

[Chuck Bryant]

Watch this.

[Josh Clark]

Kind of fun.

[Chuck Bryant]

Okay, so that's trilateralation. That's 2D trilateralation. Because what you've done is found your. If you were a flat point and the Earth was flat, which it's not, that's all we would need to do. But the Earth is a sphere. It's round. And so what GPS uses is 3D trilateralation, which, rather than flat circles, it uses spheres. And when the three or four, usually, because. Use four satellites where those spheres all intersect the one point, that's where you are. Because now you not only know where you are longitudinal, latitudinally, you also know where you are at altitudinally.

[Josh Clark]

My friend, I hate to break it to you, but you did the old Josh Clark insert an extra consonant thing.

[Chuck Bryant]

Trilateralizational.

[Josh Clark]

It's trilateration.

[Chuck Bryant]

I know, and I've been wanting to say trilateralization for so long. Well, you weren't even saying that off my chest.

[Josh Clark]

You were saying trilateralation.

[Chuck Bryant]

Okay, all right, so now that's three ways. So trilateration.

[Josh Clark]

Trilateration.

[Chuck Bryant]

That sounds made up like space force.

[Josh Clark]

I know.

[Chuck Bryant]

All right. Trilateration.

[Josh Clark]

Yeah, Station.

[Chuck Bryant]

So that's it? That's how you figure. Well, I should say that's how your GPS receiver figures that out. It knows where those three or four satellites are because they tell it where they are. It figures out the distance between you and your receiver for each of those four, and it tells it. Oh, here's where I am. Because here's where all those that information intersects.

[Josh Clark]

Right. And I think you mentioned the spheres while I was obsessing about the extra L. Right?

[Chuck Bryant]

Yes, I did.

[Josh Clark]

Okay, great.

[Chuck Bryant]

And there's a really pretty image out there. I can't remember what website I found it on, but if you search, like, how GPS trilateration works, it will come up, I'm sure. But it shows, like, the four spheres created by the satellites and they're all in four different primary colors. And it's so pretty.

[Josh Clark]

I saw it.

[Chuck Bryant]

Yeah, I understand that there are three primary colors, but whatever the fourth one is, it's basically a primary color as far as I'm concerned.

[Josh Clark]

Okay, should we take our second break?

[Chuck Bryant]

Yeah, I think so, Chuck. We earned it with that trilateralation, trilateration. Explanation. Explanation.

[Josh Clark]

We'll be right back.

[Will]

Hey, Will, do you ever get overwhelmed by how much science happens these days?

[Mango]

Constantly. I'm like, ah, there's so much science, I can't keep track of it all.

[Will]

Then it's a good thing. Our podcast, Part Time Genius is counting down the 25 greatest science ideas from the past 25 years.

[Mango]

That's right, Mango. We're talking animals in a paper called.

[Will]

Quote, chickens prefer beautiful humans.

[Chuck Bryant]

This was actually the title of the paper.

[Will]

They all discovered that, much like humans, chickens are attracted to symmetrical faces.

[Chuck Bryant]

Got it.

[Will]

We're talking medical miracles.

[Mango]

He's an endocrinologist who found a way to stimulate insulin producing cells using, wait for it, the saliva of a Gila monster.

[Will]

There's no way to make that not sound crazy.

[Mango]

We even talked to some of the experts behind these breakthroughs. It's a week full of fact packed stories you won't want to miss. So listen to the Part Time Genius countdown of the 25 greatest science ideas of the past 25 years, starting Monday, March 3rd on the iHeartRadio app, Apple Podcasts, or wherever you get your podcast.

[Chuck Bryant]

Okay, Chuck, so there's one other thing, kind of like a little sidebar I felt like we should talk about. If you've ever tried to figure out where you are and your phone's like, turn on WI Fi and we'll get a better reading.

[Josh Clark]

I've never understood that until you explained it.

[Chuck Bryant]

So what it's trying to do is it's prompting you to turn on your WI FI based positioning system. And that is based essentially on the same thing that Dr. Gedding was getting at, which is you can use information from different sources and comparing those sources to figuring out where you are. And so rather than using satellite information, this uses the it bases it on the known strengths of different WI FI network towers antenna. And so depending on how strong one signal is compared to where you are, in addition to comparing it to another signal and another signal, another signal. It's like, oh, you're in Denver, right?

[Josh Clark]

You don't know how dumb I am.

[Chuck Bryant]

I don't think you're dumb. I know you're not dumb, but let's hear what you have to say.

[Josh Clark]

I say this out loud at the risk of losing listeners that might be new listeners and are like, I can't listen to this guy.

[Chuck Bryant]

Oh, this is really dumb.

[Josh Clark]

Up until yesterday, whenever my phone or my car or something said, turn on your WI fi to improve accuracy of your location, it's like, I'm not near my house. What is this thing asking me to do. I'm not near my wifi.

[Chuck Bryant]

You weren't like, you're not the boss of me.

[Josh Clark]

No, I was just. That's pretty dumb.

[Chuck Bryant]

I don't. No, it's not.

[Josh Clark]

WI fi is everywhere. It doesn't have to be your house, WI fi.

[Chuck Bryant]

So, yes, that's one way it does it, and it does it in your house, too. But that's because your router is a big blabbermouth and tells everybody where you are. So I gotta get it now.

[Josh Clark]

It's like, they don't know I'm not near my house. Why is it asking me to turn on my wifi?

[Chuck Bryant]

So stupid.

[Josh Clark]

Oh, boy. All right, so speaking of the opposite of stupid, your smartphone, how accurate are those things? When GPS first started, they said, and this was again, like 95ish, they said, it's going to be accurate to within 100 meters, 95% of the time. Which at the time was like, hey, that's not bad at all. Like, that gets me in the neighborhood of where I want to be. They've gotten much, much better. Now they say 2 meters, within 2 meters of 6.6ft, but it's really closer than that. They did some measuring in 2021, and the global average across all users was about just a little more than two feet. And you know, again, that depends on a lot of things. If it's got tall buildings in the way, space weather, atmospheric conditions, apparently like a really dense, like, jungle canopy or thick shrubbery can actually degrade the accuracy of that signal.

[Chuck Bryant]

Yeah, you got a hickory tree. Well, TS for you, because GPS isn't going to work.

[Josh Clark]

Is that a thick tree, thick canopy?

[Chuck Bryant]

Yeah, I would. Yeah, I think so. I mean, it's a known shade tree.

[Josh Clark]

No, it's a kst.

[Chuck Bryant]

That's right.

[Josh Clark]

Put it on the list.

[Chuck Bryant]

If it could broadcast information, it would also be a known point. Yeah, exactly. So there's a couple of other things that can mess with your GPS signal coming from the satellite. Because, remember I said that they navigate celestially. Well, if the Earth's position itself relative to the satellite, satellite can know where it is. But if the Earth shifts a little bit, like the magnetic core sloshes around just enough that the Earth kind of wobbles a little bit, or if the sea currents are particularly strong, it can slow the rotation of the Earth. Those things, I mean, just the tiniest, tiniest changes can alter the accuracy of the signal that it gets. But that's just the signal that they're like, we're going to get. You within six feet, they don't guarantee your receiver. And your receiver typically adds a little bit of inaccuracy. I think 5 meters is usually what you. What you're going to get from like your average dumb GPS receiver.

[Josh Clark]

Yeah. And I get. I mean, it's amazing we're here because if you're like GPS to just say, this is good. If you're, if you're five feet away from the restaurant or your friend and you don't see them, that's on you.

[Chuck Bryant]

Yeah, just look up.

[Josh Clark]

Yeah.

[Chuck Bryant]

So we're getting better, though, you know?

[Josh Clark]

Yeah, no, it's getting. I mean, I imagine they're going to have it, I think, March 24, if you're an ideal. If it's clear skies, you're out in the middle of the desert or something, they can be as accurate as 30cm.

[Chuck Bryant]

Which is five AA batteries end to end. We're going to get even better than that though, Chuck, because right now there's some really good GPS antenna that are starting to pop up in smartphones. And those, those are dual band, dual. A dual band, dual frequency receivers, one of those two. And that uses the L1, the standard civilian GPS band that has been around since the beginning, but it's gotten better over time. And it also uses the new Whiz Bang L5. And this is like the next generation of GPS. It's not widespread enough yet. There's not enough satellites out there that are L5 for an antenna to just rely on that. But when you put L1 and L5 together, it gets pretty good. The thing is, you might ask yourself, like, why, why would you need to get like within centimeters of the restaurant that you're going to? It doesn't make sense. Well, some people use GPS for more than just finding the restaurant that they're going to.

[Josh Clark]

Yeah, that's right. And your parents and grandparents might be using their Garmin still, so just have patience with them.

[Chuck Bryant]

I think that Garmin was actually one of the original GPS devices.

[Josh Clark]

Yeah. And it's still being used in certain cars, in certain people's families.

[Chuck Bryant]

Are those things even supported any longer?

[Josh Clark]

I don't know, man. It's pretty funny, though. It's like looking at a MySpace webpage or something when you look at it.

[Chuck Bryant]

I'll bet it is.

[Josh Clark]

But yes, I took this off task. You were talking about other things that this is used for a lot. We talked about landing airplanes. That's pretty important. Accuracy is pretty important. Maybe not down to the centimeter, but if you want to track soil moisture you can do that via gps. If you want to measure the size of a glacier and whether it's shrinking or moving, you can do that very, very accurately. And not just sort of ballpark things anymore, migration patterns. If you want to see where that school of whales is headed and how they know when they get there and how far they are from where they started, you can do that with great accuracy.

[Chuck Bryant]

Yeah. Also, things use it to basically stay in position, like modern agricultural equipment, like harvesters, they go in a straight line by themselves thanks to really precise gps. Same with self driving cars. Oh, sure, yeah. And then like apparently it's just grown so ubiquitous and so reliable that contractors use it. Like digital blueprints will have GPS coordinates for like a nail or an electrical outlet or something like that. So you can know exactly where that thing's going to go, which, I mean, that's got to cut down on construction costs and time dramatically.

[Josh Clark]

Yeah, I thought the thing on tunneling was kind of cool. I never really thought about that. But if you're tunneling through two sides of a mountain to ideally meet in the middle and have a one long tunnel, that's not one tunnel with a little zigzag in the middle because they were off by a little bit, you can do that down to the centimeter or 30 centimeters rather.

[Chuck Bryant]

Yeah, a tunnel that goes through a mountain with like a hairpin turn in the middle of it.

[Josh Clark]

That sounds great.

[Chuck Bryant]

And if you put all this stuff together, all these different uses for gps, which again, the American taxpayers give to the world for free, it generated, I think in 20, 22, $94 billion worth of stuff, Right? All of that receivers that were sold, all the tunnels that were drilled correctly, like all that stuff came to generate $94 billion. And in the next five years it's expected to hit almost 300 billion. So it's a big deal. Like we rely on GPS a lot. And so because we rely on something this much, and because like you said, we don't have a backup of GPS in particular, it can be pretty delicate, I guess you could say, to put it delicately, because it can get screwed up pretty bad pretty easily. And in fact, on a very local level, you or I could go screw up somebody's GPS for fun anytime we wanted.

[Josh Clark]

Yeah, that was a little disconcerting to learn, I thought, like, oh, well, surely this thing has just some weird robust government shield that cannot be hacked. Right? And that's not true. In fact, the military, I mean, it's part of military, just regular operations to jam GPS for Another country, their planes and drones, or to spoof it is when you send it, you know, jam it and make it non operable. But you. You're like, ooh, here's some fake coordinates that you're gonna think are real, right? Yeah, like, they do that all the time. Countries do that to us all the time. But like you said, any schmo that's got 300 bucks can get a software defined radio and figure out how to use it and jam somebody's gps. And so your neighbor's walking around wondering where that restaurant is.

[Chuck Bryant]

I know, they're like Fridays, right?

[Josh Clark]

I wanted to go to Finnegans.

[Chuck Bryant]

Yeah. So you were talking about spoofing. Apparently, Iran in 2019, just for kicks, spoofed a British cargo ship's GPS and told that it was in international waters when really they had drifted into Iranian waters. So Iran was like, oh, you're our ship now, and you're our crew now. And they held the whole thing for 10 weeks just by being jerks, apparently. I can't figure out what the point would have been for that other than to flex.

[Josh Clark]

Yeah, that is a little odd. I'm sure somebody knows. Or maybe it was a flex.

[Chuck Bryant]

Yeah. And the kids still say that, right? They flex.

[Josh Clark]

Oh, you're asking the wrong guy.

[Chuck Bryant]

Okay, well, let's say they do.

[Josh Clark]

I mean, Ruby says things I don't understand, and I just don't even ask.

[Chuck Bryant]

I know, I know. My niece Mila was schooling us on slang, and I'm like, there's no context for that. It doesn't make any sense. Yeah, I'm trying to think of one example. I know I'm gonna get it wrong.

[Josh Clark]

No cap, no.

[Chuck Bryant]

Something like skibidi.

[Josh Clark]

Oh, Skibidi toilet.

[Chuck Bryant]

Yes. And I understand, yes, it's a web video or whatever, but the videos itself make no sense whatsoever, too.

[Josh Clark]

Yeah. Hey, you know, all we did in the 80s was shorten awesome to awes and un awesome.

[Chuck Bryant]

That was our big contribution that was.

[Josh Clark]

As sophisticated as we got. I don't know about the skibidi stuff.

[Chuck Bryant]

Yeah. And I don't mean to complain. I mean, each generation, like, builds on the mask, comes up with its own stuff. I'm happy about that. I just don't understand it.

[Josh Clark]

Well, that's the point, I think.

[Chuck Bryant]

You know, I think you're right, actually, and I'm kind of hurt by that.

[Josh Clark]

Yeah, it's. You know, kids and teens come up with their own language, so adults don't know what the heck we're talking about, and they can laugh behind Our backs. Yeah, we did the same thing.

[Chuck Bryant]

I didn't.

[Josh Clark]

We said, that's very un. Us. And our parents were like, what are they saying?

[Chuck Bryant]

I can't make heads or tails of that.

[Josh Clark]

Airlines can get jammed. There was a study that found intentional jamming of airlines was a problem in three regions. Only three. More than 70,000 flights were jammed between February and August of 2022. And that, you know, once you jam it up, you can't reset it. Like, that plane lands, and then the unjamming happens.

[Chuck Bryant]

Yeah. You have to turn the whole thing off and reset everything. You can't just reset the GPS antenna.

[Josh Clark]

And they need to work out all that stuff, don't you think?

[Chuck Bryant]

They definitely do. But something about those flights being jammed. Those are civilian flights being jammed by bad actors and sometimes governments and militaries. So what you're trying to do, essentially, is to crash a plane full of people. Like, that's your shot. It's not, like, a really dedicated shot at it, but that's pretty much the of doing that to an airliner.

[Josh Clark]

Yeah. And you have no idea how much I put my hand over my mouth when you said bad actors, and I almost shouted out a few names of actors.

[Chuck Bryant]

Who are you gonna name?

[Josh Clark]

No, I can't. Cause you never know. People might listen to this. I'm sensitive to hurting people's feelings now here in my 50s.

[Chuck Bryant]

I think that's great, man. Well, text me some names, then.

[Josh Clark]

I will.

[Chuck Bryant]

Okay. There's another thing that spoofing, I believe. I think they use spoofing for it is to cheat at games like Pokemon Go.

[Josh Clark]

Yeah.

[Chuck Bryant]

Where you can fake where your own GPS coordinates are to say, like, oh, I'm at the. I don't know, Pikachu's lair or something like that. So give me the egg that Pikachu is guarding, which I can turn into, like, some skeeball tickets and get a combination.

[Josh Clark]

Or Skibidi toilet. I hope that doesn't mean something dirty. Right.

[Chuck Bryant]

It means nothing from what Mila's told me. Like, it's just basically a thing you say.

[Josh Clark]

Okay.

[Chuck Bryant]

I hope I'm not outing Mila as uncool, though.

[Josh Clark]

Well, I'm just glad that you have someone in your life that's down with that kind of stuff, because it's pretty vital these days.

[Chuck Bryant]

I don't know if it's vital that I know that Skibidi toilet exists, but maybe not that.

[Josh Clark]

But Skibidi toilet has its own Wikipedia entry.

[Chuck Bryant]

Oh, I believe it. Have you seen the videos, though, that it's based On.

[Josh Clark]

No, but I see a screenshot now.

[Chuck Bryant]

They're mesmerizing.

[Josh Clark]

It doesn't. It doesn't pull me in.

[Chuck Bryant]

You should watch a second or two of it. You don't need to watch much. You get the gist of it really quick. But it's like you'll find that your mouth is open. Not in awe, but just because you're glazed over.

[Josh Clark]

Right, right.

[Chuck Bryant]

So like you said, the United States is not unaware of the vulnerability. That was what I was saying. It was in a delicate position. It's vulnerable. It's a very vulnerable system. And, you know, like, globally and also locally. So they are taking steps to update it. And that is going to come in the form of adding more and more L5 satellites. That's right. But for now, if you want to be a little shocked, taking into consideration how dependent we are in GPS, the average age of a GPS, specifically the United States Global Positioning System satellites, is 13 years. Yeah, that is really old for a satellite. But, Chuck, tell them how old the oldest satellite in the constellation of GPS satellites is.

[Josh Clark]

That would be 27 years old. Is that right? Yeah.

[Chuck Bryant]

Yes. That thing has sarcopenia. Oh, I guess that's it for gps, huh?

[Josh Clark]

Yeah. This was more fun than I thought. And you know what? I'm glad we had some fun and had some laughs because that feels like a lighter tribute for Marshall than something else.

[Chuck Bryant]

For sure. Hopefully we made you proud, Marshall. And thanks again for everything. And since we said thanks to Marshall Brain, then I think it's time for listener mail.

[Josh Clark]

I'm going to call this Forget Rice. How about some peace and love? Hey, guys, Big fan of the show. I love listening when training for marathons and love the recent marathon episodes. While listening to the history of refrigeration, the ref RICE method for managing a musculoskeletal injury was mentioned. Did you know, guys, that in 2020, the medical world threw out the rice method and transitioned to peace and love?

[Chuck Bryant]

I don't even remember mentioning that, let alone knowing that tidbit.

[Josh Clark]

I think I probably did. So for peace and love, we have protection. Avoid activities that cause pain for two days, three days elevation. The A is avoid anti inflammatories because apparently that reduces healing. And you should avoid ice, too.

[Chuck Bryant]

I have heard that that anti inflammatories are actually not very good for you.

[Josh Clark]

I just. I never take those anyway because I don't really need to.

[Chuck Bryant]

But yeah, lucky some people really need them.

[Josh Clark]

I know. I'm sure. Where was I? A so down to C compression, E education which is avoid unnecessary passive treatments. Your body will heal. So I guess educate yourself.

[Chuck Bryant]

They were like, we really need an E here.

[Josh Clark]

Yeah, basically. And then we and is not spelled out but love is load. Let your pain be your guide. Optimism, condition your brain Vascularization, pain free cardio and exercise. Restore mobility through active approach and Sarah says this is a lot. I hope people can learn to avoid ice and anti inflammatories for optimal recovery, but it's having a hard time catching on.

[Chuck Bryant]

I can't imagine why.

[Josh Clark]

That is from Sarah PT Bird Nerd Hollingsworth. And she's a bird nerd and loves our bird episodes.

[Chuck Bryant]

That's awesome. Thanks, Sarah. Way to spread the good word. I know there's a lot of good advice and information in there, but it's just going to take months of digesting that information to try to figure out those acronyms.

[Josh Clark]

Yeah.

[Chuck Bryant]

If you want to be like Sarah and put something on our radar that we weren't aware of before, we love that kind of thing. You can send it to us via email like Sarah did to stuffpodcastheartradio.com.

[Josh Clark]

Stuff you should know is a production of iHeartRadio. For more podcasts My Heart Radio, visit the iHeartRadio app, Apple Podcasts, or wherever.

[Cheekies]

You listen to your favorite shows.

[Questlove]

Hey everybody, what's up? This is Questlove, and every year we do special programming in February for Black History Month. Now, it's especially important this year as we gear up for some new conversations. So the team and I compiled some clips from the show that are worth revisiting in part one of the celebration of Black History Month. We're listening back to Moments with Chris Rock, Solange Prodigy, Ben Vereen, Jennifer Lewis, Angela Rye and Gina Yashore. Listen to Questlove supreme on the iHeartRadio app, Apple Podcasts, or wherever you get your podcast.

[Paola Pedrosa]

Welcome. My name is Paola Pedrosa, a medium and the host of the Ghost Therapy podcast, where it's not just about connecting with deceased loved ones, it's about learning through them and their new perspective. I think God sent me this gift so I can show it to the world. And most of all, I help people every single day. Listen to the Ghost Therapy podcast on the iHeartRadio app, Apple Podcasts or wherever you get your podcasts.

[Cheekies]

Hey, y'all, it's your girl, Cheekies. And I'm back with a brand new season of your favorite podcast, Cheekies and Chill. I'll be sharing even more personal stories with you guys and as always, you'll get my exclusive take on topics like love, personal growth, health, family ties, and more. And don't forget, I'll also be dishing out my best advice to you on episodes of Dear Cheekies. It's going to be an exciting year, and I hope that you can join me, listen to Cheekies and chill season four on the iHeartRadio app, Apple Podcast, or wherever you get your podcasts.