Welcome to tech Stuff, a production from iHeartRadio. Hey theren Welcome to tech Stuff. I'm your host, Jonathan Strickland. I'm an executive producer with iHeart Podcasts and how the tech are you well. I am finishing up my vacation down in floridaar and I will be back in Atlanta next week. In the meantime, I do have an episode for you. This one published on March eleventh, twenty twenty. It is titled SETI Not at Home. It's about the SETI at Home program, a program that crowdsourced the search for extraterrestrial intelligence, and why it shut down in March of twenty twenty. At least the crowdsource part. The program itself has not shut down, to be clear, but the crowdsource part has. Let's find out why. As I record, it is early March twenty twenty, just days after I received some devastating news. Technically, the whole world received this news. I'm just taking it particularly hard. I heard that the distributed computing project SETI at Home is shutting down, at least for a while. It's going on hiatus by the end of March twenty twenty. Now for two decades. This project has been relying on computer processing cycles provided by people like all of you guys out there, just using regular computer processors rather than some sort of massive supercomputer. Why was it making use of that, Well, it was coming through massive amounts of information gathered by radio telescopes in search for signals created not through some natural cosmological process, but rather as evidence of intelligent communication. SETI, you see, stands for the search for extraterrestrial intelligence. Now, in this episode, I'm going to talk about the history of SETI as a science, and then as well, I'm going to kind of pivot around and talk about the distributed computer programs and the SETI at Home program in particular. We'll find out how distributed computing works, we'll talk about a couple of other distributed computing programs that you could still participate in if you're so inclined, And we'll also look into what's next for SETI at Home and learn why it's going on hiatus in the first place. Now, we human beings have hypothesized about the possibility of extraterrestrial or alien intelligence for a really long time. It's a frequent topic in pop culture. But perhaps I shouldn't even use the word hypothesize, because for a really long time in our history, there really wasn't any way to test that hypothesis other than for us to look up at the sky and say, Nope, that ain't it. That would all change with the invention of the radio telescope. So it was in the nineteen twenties when an engineer named Karl Janski, working for Bell Telephone Laboratories, set the stage for radio astronomy. But that wasn't Jansky's goal at the time. He had been tasked with figuring out where the source was of some signal interference that was affecting telephone communications at that time. So in an effort to kind of figure this out, he built a directional antenna. And I guess that itself deserves its own quick explanation. So antennas can transmit and pick up signals, right, I mean, that's what they do, And it actually helps to talk about transmitters first to understand how a receiving antenna works. So a transmitter takes an electrical signal, typically one that's been boosted with amplification, and sends that signal to a transmitting antenna. We know that electricity and magnetism are related, right. We've talked about that a ton in previous episodes, and we've talked about electromagnetism and the electromagnetic spectrum a lot on this show, even recently. So, if you run a current through a conductor, it generates electromagnetic waves, including if the conductor's big enough, radio waves. Now on the electromagnetic spectrum, radio waves have the longest wavelengths if you look across that spectrum. They are a non ionizing form of radiation, meaning they lack the power to strip electrons away from atoms, and they aren't harmful the way stuff like X rays or gamma rays are. So you can wander around and have radio waves hitting you. It's not going to affect you in any way. You won't even notice. Okay, So, sending a powerful electrical current through a big conductor generates radio waves along with other electromagnetic radiation code information on radio waves by altering that signal in some way. Otherwise you're just sending out a long, steady tone like a sin wave. The two main ways to do this are frequency modulation, in which you change the frequency of the radio waves that you're sending out within a certain band of frequencies, or amplitude modulation in which you change the amplitude, or you can think of it as almost like the strength of the radio waves that you're sending out. That would end up being FM and AM radio respectively. All right, So receivers take that same process, but they reverse it. So as long as the signals that the antenna pickup are fluctuating in some way, then it's going to create an electric current in that antenna. So a properly tuned receiver that encounters the respective radio wave radiation will see that whole process go in reverse. The radio waves will induce electricity to flow through the antenna to whatever device the antenna's hooked up to. It might be a meter, in which case you'll see the little indicator show that there's a current running through that circuit. Or it'll be a radio so that you can listen to a radio station that way. Could be any number of things. It usually will require amplification of that signal. Typically the signal is too weak to actually power anything significant, so you would run it through an amplifier and thus take that same signal and just boost its power before sending it on to do whatever it was supposed to do. Now I've dramatically simplified this whole process. There's other stuff we could talk about that really plays an important part, like the concept of resonance, but that is really the matter for a different episode entirely, and I have covered it in previous episodes too. So essentially that's how antennas work. So Janski designed a directional antenna as opposed to an omnidirectional antenna. An omni directional antenna, as the name implies, can pick up signals transmitted from any direction from around that antenna. Like just imagine an antenna poking up straight in the air and it can accept radio waves from any direction. Now, a directional antenna is designed in such a way where it is much more sensitive at picking up signals that are coming from specific points. You have to point the antenna toward the area where you expect there to be a radio wave, and the benefit is you can pick up much weaker radio waves typically with a directional antenna than with an omni directional antenna. However, if you're a couple of degrees off, if your antenna is not pointed directly at the source, you may not pick up the signal at all. So if you have the directional antenna pointed north, for example, but the source of radio waves is to the west, then your antenna might not pick it up because it's pointed in a different direction. However, this is it's an incredibly useful tool if you're trying to look for a specific source of interference in your telephone communication system. I should also add that there's another important thing about directional antennas is that even they have a limit to how far they can pick up a signal here on Earth. And this has to do with the fact that our Earth is and brace yourselves round, it's not a flat earth, people. The way radio waves propagate and it can be transmitted and received, that alone would tell us that the Earth has to be curved. And here's the reason. When you broadcast radio waves, they travel outward in a straight line from the source of radiation. And if the Earth were flat, then no matter how far away you were, if you had a sensitive enough antenna, you'd be able to pick up radio waves from that source. However, because the Earth curves, then and you look at two different points on the planet that are far enough apart that curvature means that if you're having radio waves travel out at a straight line from point A, they won't reach point B because it's curved away from the path right, It'll those radio waves will just go out into space instead. There is an exception to this, and that certain radio waves are the right length where they can bounce off the Earth's ion a sphere. So you can use the ionosphere sort of like a mirror. You can point radio waves toward it. It will bounce off the ionosphere and then angle back down toward the surface of the Earth. That way, you could actually transmit much further than you could just from line of sight. You can think of it as a line of sight. You don't even actually have to be able to see the thing. It just has to be, like I said, a more or less straight path from point A to point B for you to pick it up. Okay, but that's beside the point. Janski's antenna was a directional antenna meant to pick up that source of interference. So he's picking up weird signals as he's using this directional antenna that don't seem to have any terrestrial source to them, Like if he pointed the directional antenna up into the air. He was picking up signals, but he could not identify where those signals were coming from. And in nineteen thirty one, after he had been scratching his head over where this source could have come from, he concluded that at least some of those signals had to be extraterrestrial in origin. They had to be coming from outside the Earth, from space itself. He didn't know where they were coming from or what was producing them, but he was sure that it wasn't coming from Earth. It was seemingly coming from the center of the Milky Way galaxy that, by the way, is the galaxy that that we're in the Milky Way. Well. Jansky published his findings in nineteen thirty two, and then he moved on to work with other stuff, with a telephone system. I mean, he wasn't an astronomer or an astrophysicist or anything like that, so he dedicated his attention elsewhere. But another American engineer named Grote Reber would build on Djanski's work, and by the way, I am certain I mispronounced his name entirely, but we're gonna soldier on. He read Janski's work and then he decided, you know what, I want to find out more about these these signals that seem to be coming from space. So he built an actual radio telescope. He set out to build a device specifically to detect these kind of signals, and so he built a bowl shaped antenna, you know, a parabolic kind of antenna in nineteen thirty seven, and it was capable of detecting radio signals from space. Now, when I say radio signals from space, I am not necessar barely talking about stuff that was purposefully or intelligently transmitted, because a lot of stuff in space generates radio waves. The Sun, for example, does it, Other stars do it. Pulsars and quasars produce radio waves. Radio astronomy gave scientists tools to detect and learn more about stuff in space than we could manage with things like optical telescopes, that is, light based telescopes. So in the decades following Reaver's work, we saw a lot of progress in astronomy thanks to radio telescopes. Now we're going to skip up to nineteen fifty seven, and that's when a telescope designed by Bernard Lovell and Charles's husband went live for the first time at Jodrell Bank at the University of Manchester and it was called the Mark one Telescope, though these days folks tend to refer to it as the Level telescope. And this thing's big. It has a parabolic dish to help focus radio waves on the antenna and that dish measures seventy six meters or two hundred and fifty feet across. A complicated analog computer consisting of electro mechanical components was designed so that it could position this antenna. It could point it at different sections of the sky, and this antenna could actually track a radio source as it moved across the sky, so you could point it at something and then use the computer to constantly adjust the radio antenna's position so that it moved along with this whatever the source was of the radio waves and you could get a better read on it. There's a really impressive piece of technology. And it also picked up the third stage of the rocket that was used to launch Sputnik. That's the first man made satellite. That's the one the Soviet Union put up into space, and it was launched just a few months after the Level Telescope came online, so it actually detected that that was one of the things that indicated how useful and important radio telescopes could be beyond just their astronomical or cosmological uses. Now, the power of the level telescope impressed a lot of very smart people, and a couple of those people were Giuseppe Cocconi and Philip Morrison. They proposed that a sufficiently powerful transmitter and a sufficiently powerful receiver would be able to send communications across vast reaches of space. So if you had parabolic antennas of particularly strong power in two different locations, you could transmit and receive radio signals even if you were light years apart from each other. Now, that communication is still restricted by the speed of light, because radio waves travel at the speed of light, and nothing goes faster than the speed of light. So if the two points of contact are let's say, eight light years apart from each other, it would take eight years for an out going message to reach the recipient and another eight years to wait for a response, so there will be no instant messaging. But beyond that, it meant that you could take a radio telescope and you could use it to search for signs that maybe someone out there in space has already been using radio technology for communications or for other purposes, and that perhaps this could help us determine if there are other examples of intelligent life out there. I'll explain more about how this was used in just a moment, but first let's take a quick break. Kochoni and Morrison wrote a paper about their proposal titled searching for Interstellar Communications. The journal Nature published this paper, and the two scientists addressed some pretty big questions. See now, as the late great Douglas Adams once observed, space is big, really big. And these radio telescopes are directional, so you have to pick a spot to point the telescope at. But how do you determine where you should look? How do you decide this is the point in space we're going to search right now? You might start off searching the equivalent of a ghost town, and it could be that a neighboring region of space might be absolutely teeming with life. But because of that directional telescope, you wouldn't know that you're just be getting data from a total uninhabited part of space. So the implication you get is, oh, there's nobody out there. Meanwhile, like two space doors down there's a raging party going on. It's kind of like if you were staring into a warehouse from the keyhole of a door. You would only see stuff within the view of that keyhole, but there could be a whole lot more warehouse just outside your area of view. You would have no idea if anything was actually in the warehouse or not. You would only be able to see from that narrow range of the keyhole. That was the same issue they were having with radio telescopes. Moreover, you could point the radio telescope at a place where there is intelligent life, but maybe it's at a region that's so far away from the Earth we can't detect that life. So let me put that another way. Human beings started broadcasting radio in the early nineteen hundreds, so it's really been less than one hundred and fifty years since we started using radio for communication. There are stars in the Milky Way Galaxy again, the same galaxy that our solar system is in, that are around nine hundred thousand light years away from us. That means it would take light nine hundred thousand earth years to travel from that distant star to us, So it takes nearly a million years for that information to get to us. A radio communication would require the same amount of time to get to us. That means that if intelligent alien life exists, or even existed on a planet around that distant star, that life would have had to have invented and made use of radio technology a million years ago for us to pick up those signals today. That's assuming that intelligent life would have somehow survived that million years. For us to say that intelligent life exists today, right, we wouldn't know that for sure. All we could say is there appears to have been an intelligent civilization that existed a million years ago. We aren't really sure what they're up to now, because we'd have no way of knowing. We would only know from the signals that were sent from the past. A neat thing about space too, The further you look, the more you're looking into the past, you're not seeing present situations just because of the restriction of the speed of light. So you'd only really be able to see any current alien civilization if they were relatively close to us, because otherwise you can't be certain that that civilization still exists if it's thousands of light years away. Moreover, alien civilizations would only have been able to hear us if they were around one hundred and fifty light years or closer to Earth. If they're further than one hundred and fifty light years away, then our broadcasts would not have gone far enough out to reach them. This, by the way, is why a lot of science fiction stories are really more like fantasy stories. A lot of them involve aliens finding out about Earth because they picked up a radio or television broadcast. But those broadcasts have only been around for a few decades, so that would require the alien to be relatively close to Earth in the first place to pick up those transmissions because of those limitations of the speed of light. Anyway, my point was, we might be quote unquote looking at the right spot, but the right spot might be far enough away that any radio broadcasts would still be in transit to us and wouldn't have arrived yet. It may not arrive for thousands of years. And that's just one more tiny part of why looking for meaningful signals in the sky is a huge challenge. You've heard the phrase looking for a needle in a haystack. Well, it's like that, but you know, roughly a bazillion times harder than that. Kachoni and Morrison set out an argument about which areas of the galaxy would be most likely to host an intelligent civilization capable of radio transmissions. This included targeting stars that are neither too hot nor too small or cold. Hot stars burn out quickly, and the thought was, if it's a really hot star, it might go through its life cycle fast enough that life doesn't have a chance to evolve on any planets that might be an orbit around that star. So the stars life cycle is literally too short for life to have formed around that system. Smaller, colder stars tend to be the really old ones, ones that have been around for billions of years, and with that much time, eventually, orbiting planets will lock on a star so that one side of the planet always faces the star and the opposite side of the planet always faces away from the star. So one side is always lit and the other side is always dark, and that kind of planet would probably be incapable of supporting life. So, said Cochoni and Morrison, we should look for stars that are not that different from the Sun. These would be the right age and size to potentially support life if an orbiting planet were within a certain range, which we tend to refer to as the Goldilocks region. It has to be a distance that's not too close to the Sun but not too far away either, and that really narrows things down in fact, and it means we can cross off potentially thousands or millions of stars from our otherwise unmanageably huge list of potential targets to look at. And so with this in mind, another astronomer and an astrophysicist named Frank Drake decided to take this hypothesis and to actually put it in action. He conducted the first search for extraterrestrial intelligence with the help of radio astronomy, and it was called Project Ozma, named after the character Ozma from L. Frank Baum's oz books. Drake secured time on a radio telescope that measured twenty six meters or eighty five feet across to scan for radio frequencies that originated out of Tao Seti and Epsilon Eridani. Those are two different stars, and both stars are relatively close to our own solar system, and both our Sun like enough that they could serve as potentially good targets. Based on Kochoni and Morrison's proposed guidelines. Apart from one outlier, his team found no evidence of radio signals indicating potential intelligent communication. The one outlier they did pick up, while initially interesting, proved to be terrestrial in nature, meaning that it originated from an aircraft made by dull old humans, didn't come from outer space. It was something that we had created and this radio telescope just happened to pick it up. And that actually illustrates another challenge with using radio telescopes, weeding out the signals that are actually coming from us as opposed to coming from space. And it sure would be embarrassing to come forward with a claim that you've discovered alien communication only for it to turn out to be a terrestrial signal, like an old Mork and Mindy episode, or something that's only got a character who's supposed to be an alien in it, it's not actually alien. Now, Luckily, this early experience taught researchers to include a secondary antenna that would only be sensitive enough to detect terrestrial signals. So you put this secondary antenna near the first antenna. They're both pointed at the same section of sky, and then when you get a beep, you know you register a signal. You can compare the primary telescope, the one that you're using to search for extraterrestrial intelligence, against this smaller antenna, and if the smaller antenna also picked up the signal, you know that signal was terrestrial, because the smaller antenna isn't powerful enough to pick up stuff from outer space. So you say, all right, well, if it appears on both, we know that that came from Earth. We know that that's not actually a signal scent from somewhere out in space. So they learned that lesson very quickly, and that was very helpful. Drake further contributed to the discourse about the search for extraterrestrial intelligence by proposing a way to sort of conceptualize the possibility of detecting intelligent civilizations in the universe these days. We call it the Drake equation and it's a pretty cool concept, and it goes something like this. All right, there's a variable that we're going to call N. N represents the number of civilizations in our galaxy with which we could possibly communicate. So N is that number. It's an unknown number. What determines the value of that number, Well, it's a bunch of stuff that you have to take into account, and that includes the average rate at which stars form in the Milky Way, the number of those stars that will actually have planets form around them, because not every star has planets, the average number of those planets that could potentially support life, the number of planets that could support life that actually go on to support life. So far, we haven't found any that definitively fit that definition. Then the number of those planets in which the life that forms can develop to the point of gaining intelligence, the number of planets with intelligent life that then develop and use communication tools that would be detectable from Earth. And then the length of time such civilizations have been doing that, because that length of time will determine whether or not they would be detectable. Right, so, even if they exist, again, if they're far far away, there's no way we could detect them anyway, because again the speed of light is a limiting factor. So this equation is not meant to give us a hard and fast number like three or something. Instead, it helps us frame the likelihood of detecting intelligent life, specifically intelligent life that is using radio communication. We don't really know anything about the number of plants that can definitively support life or anything else beyond that particular variable. Right, we got information about some of the other stuff. We have a general idea of how frequently stars form in the Milky Way. We are refining our understanding of how many stars have planets. Turns out that way more stars have planets than we initially thought. Then we have to think, all right, well, how many of those plants could potentially support life based upon their distance from the star, the age of the star, the heat of the star, all of those other variables. So we're slowly learning more about the front half of that equation, and the back half is still largely a mystery to us. Now it's important so that we can use that kind of information to help refine our search. Right, we want to make sure that we are looking at the places most likely to produce good results, because again, space is really big. If we just randomly point the telescope in any given direction, the odds of success are minuscule. We want to improve those odds as best we can by making some intelligent decisions based on educated guesses. Really. Now, the Seti Institute, a not for profit scientific research organization, wouldn't come into being until nineteen eighty four. However, between Drake's project Ozma in the early nineteen sixties and the SETI Institute's formation in nineteen eighty four, there were lots of astronomers who were looking for signals that might have originated from an intelligent civilization out in space. I find a lot of people confuse SETI the science that's the general science of searching for extraterrestrial intelligence, and SETI the institute. Those are The SETI Institute is dedicated toward a deeper understanding of life in general and its place in the universe and the potential existence of extraterrestrial intelligence. But the two are not synonymous. It's not SETI and the SETI Institute are related but distinct. Now, back in nineteen sixty seven, there was an astronomer named Jocelyn Bell who noticed something that initially seemed really promising from a SETI perspective. Turned out it was incredible information period, but we just didn't understand its significance at the time. She noticed what appeared to be a pulsing radio signal. She and her supervisor charted the pulses that they were detecting and they were detecting them at regular intervals, like each day, slightly off by hours or whatever. But it was it was unusual. They weren't expecting it, and at the time they didn't have an explanation for the origin of those radio pulses, so they had to label it as something, and at the time they labeled it LGM ie. LGM stood for Little Green Men. It was a somewhat tongue in cheek way to indicate that, I don't know, maybe this is purposeful radio broadcasting. We don't know. They kept looking into it, they kept trying to figure out exactly what it was and where the signal was originating from, and over time they concluded that it was actually a naturally occurring pulse. It was not like an outgoing phone message from beyond the stars or something. Ultimately, this hunch that they had that it was a naturally occurring phenomenon proved correct, and scientists were able to figure out that the pulse was coming from rotating neutron stars called pulsars. So while it didn't turn out to be aliens, astronomers were able to expand our understanding of space, so it was still super cool. It just you know it wasn't aliens. Ohio State University launched the first long term SETI study in nineteen seventy three, and unlike other attempts, this one surveyed the entire night sky as the Earth rotated. Instead of honing in on a specific region of space and then just staying locked onto that region, it would do a full scan every night, slightly different arc each night, full scan of the night sky. In nineteen seventy seven, that system registered a signal that was many times stronger than the background signals that the telescope was recording. There was an analyst named Jerry Emmon who wrote down the word wow in the margin of the computer print out for that detection, and to this day we call it the Wow signal. And the signal had a profile that suggested it wasn't your typical, naturally occurring radio wave. It was this weird spike. But despite numerous efforts, the telescope did not pick up any subsequent signals from that part of space. Emmon himself later guessed that perhaps the signal originated from Earth. Maybe it was something that got beamed up and then reflected off of something in space, like a piece of space debris and thus it didn't originate from extraterrestrial sources at all, but we don't know for sure. Astronomers oversaw similar efforts with different radio telescopes around the world over the years, and it's a bit tricky because it requires securing time on radio telescopes for the purposes of searching for extraterrestrial intelligence, and the owners of those telescopes frequently scientific research institutions universities that kind of thing. They often have their own priorities which may or may not involve seeking out evidence of intelligent life in the galaxy. So finding time when you can use those radio telescopes is pretty tricky stuff. In nineteen eighty four, Thomas Pearson and Jill Tarter found the not for profit organization called the SETI Institute, with the mission to understand life and a sort of universal context. So again, while there is a SETI organization, SETI as a whole really refers to the science the effort, the specific application of techniques and processes, and an effort to attain a particular outcome, namely to find evidence of extraterrestrial intelligence. Astronomers interested in pursuing goals related to SETI often have to wait for times when telescopes aren't in active use for some other purpose, and that really limits what they can accomplish. Other groups have developed a way to piggyback onto existing radio telescopes. So piggyback systems tend to be systems that monitor data picked up by a radio telescope, so it's like an additional computer readout of what's going on. So the team that's using the radio telescope is doing it to do some specific purpose. Meanwhile, SETI researchers are using a parallel readout, just looking for anything that might stand out as a potential example of evidence for extraterrestrial intelligence. This is tricky because again the SETI researchers have no say on where a telescope's going to be pointed. They're just looking at the same data, but for a different reason. So it's not ideal. But again, yeah, telescopes are kind of hard to come by. Even with all these limitations, scientists were generating a lot of information that they needed to sift through. Radio telescopes pick up a lot of noise, and there may be signal in that noise. I mean that signal might be incredibly weak, but you have to really examine the data closely in order to figure out what is truly a signal versus just random noise in the background. And then you have to weed out all the other stuff like did that signal come from a natural phenomenon? Did it come from a terrestrial source. This is not easy to do. Scientists were already having to work pretty hard to secure time with radio telescopes. It would be even harder to secure time with something like a supercomputer because supercomputers also are owned by just a few different universities and research organizations and labs, and they typically are being used for other stuff that takes a higher priority than searching for extraterrestrial and dilligence. And then there was a breakthrough, and that breakthrough came in the form of network connectivity. In the early nineteen nineties, the mainstream public first began learning about this weird thing called the Internet, and by nineteen ninety nine, the Internet was, if not a household term, at least something most folks had some experience or knowledge of. And that's what opened up the opportunity for SETI at home. I'll explain more in just a minute, but first let's take another quick break, So there are many different models for computing. When I was growing up, I was familiar with a more centralized model. So in my case, I was growing up in the era of personal computers, and the computers I first used were completely self contained. They didn't connect to a larger network. All the processing capability, all the programs, all the capacity for storage were connected to the physical computer itself. They might be peripherals, but it was all part of the personal computer. A few years ago, the big trend was cloud computing. So with cloud computing, you've got networked servers that are doing a lot of the processing power for big applications. The devices we're using, whether they're computers or mobile devices or sensors or whatever, are mostly acting as transmitters and receivers for many tasks. We provide input to these devices, and the device then transmits commands to some distant group of servers that takes that information, does some sort of operation on it, produces some sort of result, and sends that back to us. So no longer do we have to have really powerful computers directly at our disposal. We can rely on cloud services to do that computing for us, at least for some things. For other things like if you want to do low latency, high graphics fidelity gaming, for example, you want to have a really good, strong computer processor at your disposal because latency with transmission can completely ruin that experience. But for the most part, you get what I'm saying well. SETTI at Home was an example of sort of a third model called distributed computing. The idea was that you could take a group of regular old personal computers, the kind that any average person could have in their home. You would install some software on those computers, and that software would allow the computers to process chunks of data in some particular way before sending the results back to wherever that data was coming from in the first place. So if someone needed to tackle a really big data processing job, one that could be divided up into smaller chunks, that person could use a centralized computer or maybe a network of computers to send out these smaller unks of data to this distribution of personal computers for processing and then wait for the results to come back, and then group them all together and see what you got. It speeds things up considerably. It increases the processing assets of the project. As more computers joined that project and it reduces the need to turn to stuff like supercomputers, and it also achieved another goal which the founders of the project had in mind, which was to encourage enthusiasm and excitement around the subject of science. Computer scientist David Gedge, astronomers Woody Sullivan and Dan Wertheimer, and David Anderson, who was David's graduate school advisor, collectively came up with this idea all the way back in nineteen ninety nine, specifically with SETI at Home. They were trying to come up with a scientific application people would be excited to participate in, and while they weren't necessarily super optimistic that SETI at Home would produce incredible results from a scientific perspective, they thought from a motivating perspective, it was just the ticket, and it was pretty genius. Upon launch, anyone with a computer and an Internet connection could conceivably help in the search for extraterrestrial intelligence. The researchers created a screen saver program, so if you wanted to participate, you could download the screen saver and install it on your personal computer. When your computer would go idle and activate the screen saver, the processor of your computer, which otherwise would be doing very little would get to work on some data sent over from the SETI research project. So the research project would pull information from a radio telescope divided into chunks and then parcel it out to people participating in this project when complete, when your processor was done working on chunk of data, it would send the results back to the central point for the project and wait for the next chunk of data. And if you were to come back to do some work on your computer, let's say you come back after taking a break for half an hour, the screensaver goes inactive and the program would surrender your processing cycles back to you, so you didn't have to worry about SETI at home suddenly taking up all of your computer's processing power. It would only jump back onto the job when your computer went idle again and your CPU had availability. Now, as I said, this idea was genius, but the original implementation of the idea was less. So now that's not a slight on the researchers, because when they launched the project in May nineteen ninety nine, they were expecting that they might get as many as a thousand people signing up. They figured that, well, this is an interesting idea and we'll probably see some folks really you know, who are really into science join, but I'm not sure about anything beyond that. Now, with that expectation, they only dedicated a single desktop PC for the purposes of assigning processing tasks and receiving the results from the distributed computers. They did not anticipate how enthusiastic the reception to the project would be. They didn't see a thousand people sign up when they launched SETI at Home. They saw a million people sign up. So let's put that into perspective. Let's say you've set up a lemonade stand and you did some brief scouting work and you anticipated that the location you're setting up in you're gonna see maybe ten customers in thirty minutes, and you think that's manageable. Well, what you didn't realize is that you've actually set up your stand in sourpuss scurvy town. It's a town populated entirely by people with an unquenchable thirst for lemonade. So instead of ten people showing up in that first half hour, ten thousand people mob your lemonade stand. You are overwhelmed. Well, the same thing happened to the SETI at Home PC that was in charge of sending out and receiving all that data. It was a good problem to have, but it was still a problem. Sun Microsystems jumped in and donated a bunch of computers to help the SETI at Home administrators make the system work, and from that moment on the program went into high gear. People in the program were contributing to scientific exploration just by allowing their idle computers to focus on complicated mathematical problems when the computer was otherwise not in use. It was a beautiful thing. The response also meant that the project could go through information orders of magnitude faster than if it had all been handled in house. They had the advantage of a million processors. That's something that no SETI project could have afforded on its own at that time. It also inspired other scientific projects to launch distributed computing efforts. Folding at Home, for example, taps into idle computers to solve protein folding problems that could lead to incredible advances in medicine and biology. On top of that, online communities formed around SETI at Home. People connected over forums and formed friendships. There were even stories about people meeting online, falling in love, and getting married out in the real world, all while using their computers to seek out evidence of intelligent life. It was all really remarkable and beautiful. But hey, if it was so super cool, why the heck is the project shutting down now? Twenty one years after it launched? Is the book closed on extraterrestrial intelligent life? Are we done? Have we given up? Well? Not quite. The problem now is that we've got a ton a mountain of processed data from this project that has to be further analyzed, and that taps into something else that I plan to talk about more later on this year, the challenges of big data. We're able to collect mind staggeringly huge amounts of information, but understanding and using that information is another matter. It presents a really big challenge. Even with all of these analyzed chunks of info, that data still has to be processed to see what's actually been found over the two decades of SETI at Home. The researchers overseeing SETI at Home hope to publish a paper on the subject, and to do that they need to look at all the results of the stuff that the program actually found, and so they needed to stop gathering data. While that happens, they have to actually stop so that they can see what they have, as opposed to continuously adding to that pile. This hiatus will allow the team to look at the results, form conclusions, and write a paper based on the whole project. And while we don't anticipate any reports of intelligent communications popping up as a result of this analysis, the endeavor as a whole has been really successful, particularly in the context of getting people excited about participating in science. On the back end of SETI at Home is an infrastructure that grew over time. It is called the Berkeley Open Infrastructure for Network Computing. This support system hosts numerous distributed computing projects that work on the same basic principles as SETI at Home. It's just that each of these projects have a different goal or purpose. Some are dedicated to detecting and measuring asteroids. Some provide cern processing capabilities to help analyze data produced by the Large Hadron Collider in an effort to gain a deeper understanding of particle physics and quantum mechanics. There are projects that focus on climate science, physics, cognitive science, and more, and you can check them all out at boink dot Berkeley dot edu, slide projects dot php. That's bo I Inc. Dot Berkeley dot edu. Slash projects dot php. If you want to dedicate some of your computer's idle processing power to solving really interesting problems in science, it's a great way to contribute. You're not even doing anything active, but you are helping, you know, peel back the border of our understanding. We're pushing that boundary further and further out, and you can do it just with your computer's idle time. It's pretty incredible. So, while SETI at Home is writing off into the sunset, at least for a while, anyway, there are still efforts around the world dedicated in full or in part to the search for extraterrestrial life. The search hasn't ended yet, even if SETI at Home is, at least for now over And while we don't have anything jumping out to us as a positive appslcely yes, we need to check this out. We're pretty sure someone's talking to us. Kind of incident. It's good to remember that space is really big. Who knows, maybe the next star we point a telescope at will be beaming whatever the alien version of the Great British bakeoff is one can only hope, and that wraps up this episode of Tech Stuff. My hat is off to the SETI at Home crew. I think it was an admirable use of technology to inspire people to get into science. I think it was a worthy endeavor to search for extraterrestrial intelligence. It was great to see other projects take that same model and apply it to their own scientific endeavors. So it's to me one of those great stories in technology. Even if we didn't find any direct evidence of little green men out there, who knows what the future will bring. If you enjoyed that episode from March eleventh, twenty twenty, SETI Not at Home, I will be back next week with all new episodes. I miss you guys so much. Trust me. Every time I'm getting my picture taken with Mickey Mouse or Rapunzel or Aeriel, my two favorite princesses, I'm thinking of y'all and wishing you could all be there to be in a big group photo with me. Maybe someday we'll organize a big Tech Stuff trip to Disney World and I'll talk all the way through the Haunted Mansion ride until they tell me to leave, until then I hope you're all well, and I'll talk to you again really soon. Tech Stuff is an iHeartRadio production. For more podcasts from iHeartRadio, visit the iHeartRadio app, Apple Podcasts, or wherever you listen to your favorite shows.

Welcome to tech Stuff, a production from iHeartRadio. Hey theren Welcome to tech Stuff. I'm your host, Jonathan Strickland. I'm an executive producer with iHeart Podcasts and how the tech are you well. I am finishing up my vacation down in floridaar and I will be back in Atlanta next week. In the meantime, I do have an episode for you. This one published on March eleventh, twenty twenty. It is titled SETI Not at Home. It's about the SETI at Home program, a program that crowdsourced the search for extraterrestrial intelligence, and why it shut down in March of twenty twenty. At least the crowdsource part. The program itself has not shut down, to be clear, but the crowdsource part has. Let's find out why. As I record, it is early March twenty twenty, just days after I received some devastating news. Technically, the whole world received this news. I'm just taking it particularly hard. I heard that the distributed computing project SETI at Home is shutting down, at least for a while. It's going on hiatus by the end of March twenty twenty. Now for two decades. This project has been relying on computer processing cycles provided by people like all of you guys out there, just using regular computer processors rather than some sort of massive supercomputer. Why was it making use of that, Well, it was coming through massive amounts of information gathered by radio telescopes in search for signals created not through some natural cosmological process, but rather as evidence of intelligent communication. SETI, you see, stands for the search for extraterrestrial intelligence. Now, in this episode, I'm going to talk about the history of SETI as a science, and then as well, I'm going to kind of pivot around and talk about the distributed computer programs and the SETI at Home program in particular. We'll find out how distributed computing works, we'll talk about a couple of other distributed computing programs that you could still participate in if you're so inclined, And we'll also look into what's next for SETI at Home and learn why it's going on hiatus in the first place. Now, we human beings have hypothesized about the possibility of extraterrestrial or alien intelligence for a really long time. It's a frequent topic in pop culture. But perhaps I shouldn't even use the word hypothesize, because for a really long time in our history, there really wasn't any way to test that hypothesis other than for us to look up at the sky and say, Nope, that ain't it. That would all change with the invention of the radio telescope. So it was in the nineteen twenties when an engineer named Karl Janski, working for Bell Telephone Laboratories, set the stage for radio astronomy. But that wasn't Jansky's goal at the time. He had been tasked with figuring out where the source was of some signal interference that was affecting telephone communications at that time. So in an effort to kind of figure this out, he built a directional antenna. And I guess that itself deserves its own quick explanation. So antennas can transmit and pick up signals, right, I mean, that's what they do, And it actually helps to talk about transmitters first to understand how a receiving antenna works. So a transmitter takes an electrical signal, typically one that's been boosted with amplification, and sends that signal to a transmitting antenna. We know that electricity and magnetism are related, right. We've talked about that a ton in previous episodes, and we've talked about electromagnetism and the electromagnetic spectrum a lot on this show, even recently. So, if you run a current through a conductor, it generates electromagnetic waves, including if the conductor's big enough, radio waves. Now on the electromagnetic spectrum, radio waves have the longest wavelengths if you look across that spectrum. They are a non ionizing form of radiation, meaning they lack the power to strip electrons away from atoms, and they aren't harmful the way stuff like X rays or gamma rays are. So you can wander around and have radio waves hitting you. It's not going to affect you in any way. You won't even notice. Okay, So, sending a powerful electrical current through a big conductor generates radio waves along with other electromagnetic radiation code information on radio waves by altering that signal in some way. Otherwise you're just sending out a long, steady tone like a sin wave. The two main ways to do this are frequency modulation, in which you change the frequency of the radio waves that you're sending out within a certain band of frequencies, or amplitude modulation in which you change the amplitude, or you can think of it as almost like the strength of the radio waves that you're sending out. That would end up being FM and AM radio respectively. All right, So receivers take that same process, but they reverse it. So as long as the signals that the antenna pickup are fluctuating in some way, then it's going to create an electric current in that antenna. So a properly tuned receiver that encounters the respective radio wave radiation will see that whole process go in reverse. The radio waves will induce electricity to flow through the antenna to whatever device the antenna's hooked up to. It might be a meter, in which case you'll see the little indicator show that there's a current running through that circuit. Or it'll be a radio so that you can listen to a radio station that way. Could be any number of things. It usually will require amplification of that signal. Typically the signal is too weak to actually power anything significant, so you would run it through an amplifier and thus take that same signal and just boost its power before sending it on to do whatever it was supposed to do. Now I've dramatically simplified this whole process. There's other stuff we could talk about that really plays an important part, like the concept of resonance, but that is really the matter for a different episode entirely, and I have covered it in previous episodes too. So essentially that's how antennas work. So Janski designed a directional antenna as opposed to an omnidirectional antenna. An omni directional antenna, as the name implies, can pick up signals transmitted from any direction from around that antenna. Like just imagine an antenna poking up straight in the air and it can accept radio waves from any direction. Now, a directional antenna is designed in such a way where it is much more sensitive at picking up signals that are coming from specific points. You have to point the antenna toward the area where you expect there to be a radio wave, and the benefit is you can pick up much weaker radio waves typically with a directional antenna than with an omni directional antenna. However, if you're a couple of degrees off, if your antenna is not pointed directly at the source, you may not pick up the signal at all. So if you have the directional antenna pointed north, for example, but the source of radio waves is to the west, then your antenna might not pick it up because it's pointed in a different direction. However, this is it's an incredibly useful tool if you're trying to look for a specific source of interference in your telephone communication system. I should also add that there's another important thing about directional antennas is that even they have a limit to how far they can pick up a signal here on Earth. And this has to do with the fact that our Earth is and brace yourselves round, it's not a flat earth, people. The way radio waves propagate and it can be transmitted and received, that alone would tell us that the Earth has to be curved. And here's the reason. When you broadcast radio waves, they travel outward in a straight line from the source of radiation. And if the Earth were flat, then no matter how far away you were, if you had a sensitive enough antenna, you'd be able to pick up radio waves from that source. However, because the Earth curves, then and you look at two different points on the planet that are far enough apart that curvature means that if you're having radio waves travel out at a straight line from point A, they won't reach point B because it's curved away from the path right, It'll those radio waves will just go out into space instead. There is an exception to this, and that certain radio waves are the right length where they can bounce off the Earth's ion a sphere. So you can use the ionosphere sort of like a mirror. You can point radio waves toward it. It will bounce off the ionosphere and then angle back down toward the surface of the Earth. That way, you could actually transmit much further than you could just from line of sight. You can think of it as a line of sight. You don't even actually have to be able to see the thing. It just has to be, like I said, a more or less straight path from point A to point B for you to pick it up. Okay, but that's beside the point. Janski's antenna was a directional antenna meant to pick up that source of interference. So he's picking up weird signals as he's using this directional antenna that don't seem to have any terrestrial source to them, Like if he pointed the directional antenna up into the air. He was picking up signals, but he could not identify where those signals were coming from. And in nineteen thirty one, after he had been scratching his head over where this source could have come from, he concluded that at least some of those signals had to be extraterrestrial in origin. They had to be coming from outside the Earth, from space itself. He didn't know where they were coming from or what was producing them, but he was sure that it wasn't coming from Earth. It was seemingly coming from the center of the Milky Way galaxy that, by the way, is the galaxy that that we're in the Milky Way. Well. Jansky published his findings in nineteen thirty two, and then he moved on to work with other stuff, with a telephone system. I mean, he wasn't an astronomer or an astrophysicist or anything like that, so he dedicated his attention elsewhere. But another American engineer named Grote Reber would build on Djanski's work, and by the way, I am certain I mispronounced his name entirely, but we're gonna soldier on. He read Janski's work and then he decided, you know what, I want to find out more about these these signals that seem to be coming from space. So he built an actual radio telescope. He set out to build a device specifically to detect these kind of signals, and so he built a bowl shaped antenna, you know, a parabolic kind of antenna in nineteen thirty seven, and it was capable of detecting radio signals from space. Now, when I say radio signals from space, I am not necessar barely talking about stuff that was purposefully or intelligently transmitted, because a lot of stuff in space generates radio waves. The Sun, for example, does it, Other stars do it. Pulsars and quasars produce radio waves. Radio astronomy gave scientists tools to detect and learn more about stuff in space than we could manage with things like optical telescopes, that is, light based telescopes. So in the decades following Reaver's work, we saw a lot of progress in astronomy thanks to radio telescopes. Now we're going to skip up to nineteen fifty seven, and that's when a telescope designed by Bernard Lovell and Charles's husband went live for the first time at Jodrell Bank at the University of Manchester and it was called the Mark one Telescope, though these days folks tend to refer to it as the Level telescope. And this thing's big. It has a parabolic dish to help focus radio waves on the antenna and that dish measures seventy six meters or two hundred and fifty feet across. A complicated analog computer consisting of electro mechanical components was designed so that it could position this antenna. It could point it at different sections of the sky, and this antenna could actually track a radio source as it moved across the sky, so you could point it at something and then use the computer to constantly adjust the radio antenna's position so that it moved along with this whatever the source was of the radio waves and you could get a better read on it. There's a really impressive piece of technology. And it also picked up the third stage of the rocket that was used to launch Sputnik. That's the first man made satellite. That's the one the Soviet Union put up into space, and it was launched just a few months after the Level Telescope came online, so it actually detected that that was one of the things that indicated how useful and important radio telescopes could be beyond just their astronomical or cosmological uses. Now, the power of the level telescope impressed a lot of very smart people, and a couple of those people were Giuseppe Cocconi and Philip Morrison. They proposed that a sufficiently powerful transmitter and a sufficiently powerful receiver would be able to send communications across vast reaches of space. So if you had parabolic antennas of particularly strong power in two different locations, you could transmit and receive radio signals even if you were light years apart from each other. Now, that communication is still restricted by the speed of light, because radio waves travel at the speed of light, and nothing goes faster than the speed of light. So if the two points of contact are let's say, eight light years apart from each other, it would take eight years for an out going message to reach the recipient and another eight years to wait for a response, so there will be no instant messaging. But beyond that, it meant that you could take a radio telescope and you could use it to search for signs that maybe someone out there in space has already been using radio technology for communications or for other purposes, and that perhaps this could help us determine if there are other examples of intelligent life out there. I'll explain more about how this was used in just a moment, but first let's take a quick break. Kochoni and Morrison wrote a paper about their proposal titled searching for Interstellar Communications. The journal Nature published this paper, and the two scientists addressed some pretty big questions. See now, as the late great Douglas Adams once observed, space is big, really big. And these radio telescopes are directional, so you have to pick a spot to point the telescope at. But how do you determine where you should look? How do you decide this is the point in space we're going to search right now? You might start off searching the equivalent of a ghost town, and it could be that a neighboring region of space might be absolutely teeming with life. But because of that directional telescope, you wouldn't know that you're just be getting data from a total uninhabited part of space. So the implication you get is, oh, there's nobody out there. Meanwhile, like two space doors down there's a raging party going on. It's kind of like if you were staring into a warehouse from the keyhole of a door. You would only see stuff within the view of that keyhole, but there could be a whole lot more warehouse just outside your area of view. You would have no idea if anything was actually in the warehouse or not. You would only be able to see from that narrow range of the keyhole. That was the same issue they were having with radio telescopes. Moreover, you could point the radio telescope at a place where there is intelligent life, but maybe it's at a region that's so far away from the Earth we can't detect that life. So let me put that another way. Human beings started broadcasting radio in the early nineteen hundreds, so it's really been less than one hundred and fifty years since we started using radio for communication. There are stars in the Milky Way Galaxy again, the same galaxy that our solar system is in, that are around nine hundred thousand light years away from us. That means it would take light nine hundred thousand earth years to travel from that distant star to us, So it takes nearly a million years for that information to get to us. A radio communication would require the same amount of time to get to us. That means that if intelligent alien life exists, or even existed on a planet around that distant star, that life would have had to have invented and made use of radio technology a million years ago for us to pick up those signals today. That's assuming that intelligent life would have somehow survived that million years. For us to say that intelligent life exists today, right, we wouldn't know that for sure. All we could say is there appears to have been an intelligent civilization that existed a million years ago. We aren't really sure what they're up to now, because we'd have no way of knowing. We would only know from the signals that were sent from the past. A neat thing about space too, The further you look, the more you're looking into the past, you're not seeing present situations just because of the restriction of the speed of light. So you'd only really be able to see any current alien civilization if they were relatively close to us, because otherwise you can't be certain that that civilization still exists if it's thousands of light years away. Moreover, alien civilizations would only have been able to hear us if they were around one hundred and fifty light years or closer to Earth. If they're further than one hundred and fifty light years away, then our broadcasts would not have gone far enough out to reach them. This, by the way, is why a lot of science fiction stories are really more like fantasy stories. A lot of them involve aliens finding out about Earth because they picked up a radio or television broadcast. But those broadcasts have only been around for a few decades, so that would require the alien to be relatively close to Earth in the first place to pick up those transmissions because of those limitations of the speed of light. Anyway, my point was, we might be quote unquote looking at the right spot, but the right spot might be far enough away that any radio broadcasts would still be in transit to us and wouldn't have arrived yet. It may not arrive for thousands of years. And that's just one more tiny part of why looking for meaningful signals in the sky is a huge challenge. You've heard the phrase looking for a needle in a haystack. Well, it's like that, but you know, roughly a bazillion times harder than that. Kachoni and Morrison set out an argument about which areas of the galaxy would be most likely to host an intelligent civilization capable of radio transmissions. This included targeting stars that are neither too hot nor too small or cold. Hot stars burn out quickly, and the thought was, if it's a really hot star, it might go through its life cycle fast enough that life doesn't have a chance to evolve on any planets that might be an orbit around that star. So the stars life cycle is literally too short for life to have formed around that system. Smaller, colder stars tend to be the really old ones, ones that have been around for billions of years, and with that much time, eventually, orbiting planets will lock on a star so that one side of the planet always faces the star and the opposite side of the planet always faces away from the star. So one side is always lit and the other side is always dark, and that kind of planet would probably be incapable of supporting life. So, said Cochoni and Morrison, we should look for stars that are not that different from the Sun. These would be the right age and size to potentially support life if an orbiting planet were within a certain range, which we tend to refer to as the Goldilocks region. It has to be a distance that's not too close to the Sun but not too far away either, and that really narrows things down in fact, and it means we can cross off potentially thousands or millions of stars from our otherwise unmanageably huge list of potential targets to look at. And so with this in mind, another astronomer and an astrophysicist named Frank Drake decided to take this hypothesis and to actually put it in action. He conducted the first search for extraterrestrial intelligence with the help of radio astronomy, and it was called Project Ozma, named after the character Ozma from L. Frank Baum's oz books. Drake secured time on a radio telescope that measured twenty six meters or eighty five feet across to scan for radio frequencies that originated out of Tao Seti and Epsilon Eridani. Those are two different stars, and both stars are relatively close to our own solar system, and both our Sun like enough that they could serve as potentially good targets. Based on Kochoni and Morrison's proposed guidelines. Apart from one outlier, his team found no evidence of radio signals indicating potential intelligent communication. The one outlier they did pick up, while initially interesting, proved to be terrestrial in nature, meaning that it originated from an aircraft made by dull old humans, didn't come from outer space. It was something that we had created and this radio telescope just happened to pick it up. And that actually illustrates another challenge with using radio telescopes, weeding out the signals that are actually coming from us as opposed to coming from space. And it sure would be embarrassing to come forward with a claim that you've discovered alien communication only for it to turn out to be a terrestrial signal, like an old Mork and Mindy episode, or something that's only got a character who's supposed to be an alien in it, it's not actually alien. Now, Luckily, this early experience taught researchers to include a secondary antenna that would only be sensitive enough to detect terrestrial signals. So you put this secondary antenna near the first antenna. They're both pointed at the same section of sky, and then when you get a beep, you know you register a signal. You can compare the primary telescope, the one that you're using to search for extraterrestrial intelligence, against this smaller antenna, and if the smaller antenna also picked up the signal, you know that signal was terrestrial, because the smaller antenna isn't powerful enough to pick up stuff from outer space. So you say, all right, well, if it appears on both, we know that that came from Earth. We know that that's not actually a signal scent from somewhere out in space. So they learned that lesson very quickly, and that was very helpful. Drake further contributed to the discourse about the search for extraterrestrial intelligence by proposing a way to sort of conceptualize the possibility of detecting intelligent civilizations in the universe these days. We call it the Drake equation and it's a pretty cool concept, and it goes something like this. All right, there's a variable that we're going to call N. N represents the number of civilizations in our galaxy with which we could possibly communicate. So N is that number. It's an unknown number. What determines the value of that number, Well, it's a bunch of stuff that you have to take into account, and that includes the average rate at which stars form in the Milky Way, the number of those stars that will actually have planets form around them, because not every star has planets, the average number of those planets that could potentially support life, the number of planets that could support life that actually go on to support life. So far, we haven't found any that definitively fit that definition. Then the number of those planets in which the life that forms can develop to the point of gaining intelligence, the number of planets with intelligent life that then develop and use communication tools that would be detectable from Earth. And then the length of time such civilizations have been doing that, because that length of time will determine whether or not they would be detectable. Right, so, even if they exist, again, if they're far far away, there's no way we could detect them anyway, because again the speed of light is a limiting factor. So this equation is not meant to give us a hard and fast number like three or something. Instead, it helps us frame the likelihood of detecting intelligent life, specifically intelligent life that is using radio communication. We don't really know anything about the number of plants that can definitively support life or anything else beyond that particular variable. Right, we got information about some of the other stuff. We have a general idea of how frequently stars form in the Milky Way. We are refining our understanding of how many stars have planets. Turns out that way more stars have planets than we initially thought. Then we have to think, all right, well, how many of those plants could potentially support life based upon their distance from the star, the age of the star, the heat of the star, all of those other variables. So we're slowly learning more about the front half of that equation, and the back half is still largely a mystery to us. Now it's important so that we can use that kind of information to help refine our search. Right, we want to make sure that we are looking at the places most likely to produce good results, because again, space is really big. If we just randomly point the telescope in any given direction, the odds of success are minuscule. We want to improve those odds as best we can by making some intelligent decisions based on educated guesses. Really. Now, the Seti Institute, a not for profit scientific research organization, wouldn't come into being until nineteen eighty four. However, between Drake's project Ozma in the early nineteen sixties and the SETI Institute's formation in nineteen eighty four, there were lots of astronomers who were looking for signals that might have originated from an intelligent civilization out in space. I find a lot of people confuse SETI the science that's the general science of searching for extraterrestrial intelligence, and SETI the institute. Those are The SETI Institute is dedicated toward a deeper understanding of life in general and its place in the universe and the potential existence of extraterrestrial intelligence. But the two are not synonymous. It's not SETI and the SETI Institute are related but distinct. Now, back in nineteen sixty seven, there was an astronomer named Jocelyn Bell who noticed something that initially seemed really promising from a SETI perspective. Turned out it was incredible information period, but we just didn't understand its significance at the time. She noticed what appeared to be a pulsing radio signal. She and her supervisor charted the pulses that they were detecting and they were detecting them at regular intervals, like each day, slightly off by hours or whatever. But it was it was unusual. They weren't expecting it, and at the time they didn't have an explanation for the origin of those radio pulses, so they had to label it as something, and at the time they labeled it LGM ie. LGM stood for Little Green Men. It was a somewhat tongue in cheek way to indicate that, I don't know, maybe this is purposeful radio broadcasting. We don't know. They kept looking into it, they kept trying to figure out exactly what it was and where the signal was originating from, and over time they concluded that it was actually a naturally occurring pulse. It was not like an outgoing phone message from beyond the stars or something. Ultimately, this hunch that they had that it was a naturally occurring phenomenon proved correct, and scientists were able to figure out that the pulse was coming from rotating neutron stars called pulsars. So while it didn't turn out to be aliens, astronomers were able to expand our understanding of space, so it was still super cool. It just you know it wasn't aliens. Ohio State University launched the first long term SETI study in nineteen seventy three, and unlike other attempts, this one surveyed the entire night sky as the Earth rotated. Instead of honing in on a specific region of space and then just staying locked onto that region, it would do a full scan every night, slightly different arc each night, full scan of the night sky. In nineteen seventy seven, that system registered a signal that was many times stronger than the background signals that the telescope was recording. There was an analyst named Jerry Emmon who wrote down the word wow in the margin of the computer print out for that detection, and to this day we call it the Wow signal. And the signal had a profile that suggested it wasn't your typical, naturally occurring radio wave. It was this weird spike. But despite numerous efforts, the telescope did not pick up any subsequent signals from that part of space. Emmon himself later guessed that perhaps the signal originated from Earth. Maybe it was something that got beamed up and then reflected off of something in space, like a piece of space debris and thus it didn't originate from extraterrestrial sources at all, but we don't know for sure. Astronomers oversaw similar efforts with different radio telescopes around the world over the years, and it's a bit tricky because it requires securing time on radio telescopes for the purposes of searching for extraterrestrial intelligence, and the owners of those telescopes frequently scientific research institutions universities that kind of thing. They often have their own priorities which may or may not involve seeking out evidence of intelligent life in the galaxy. So finding time when you can use those radio telescopes is pretty tricky stuff. In nineteen eighty four, Thomas Pearson and Jill Tarter found the not for profit organization called the SETI Institute, with the mission to understand life and a sort of universal context. So again, while there is a SETI organization, SETI as a whole really refers to the science the effort, the specific application of techniques and processes, and an effort to attain a particular outcome, namely to find evidence of extraterrestrial intelligence. Astronomers interested in pursuing goals related to SETI often have to wait for times when telescopes aren't in active use for some other purpose, and that really limits what they can accomplish. Other groups have developed a way to piggyback onto existing radio telescopes. So piggyback systems tend to be systems that monitor data picked up by a radio telescope, so it's like an additional computer readout of what's going on. So the team that's using the radio telescope is doing it to do some specific purpose. Meanwhile, SETI researchers are using a parallel readout, just looking for anything that might stand out as a potential example of evidence for extraterrestrial intelligence. This is tricky because again the SETI researchers have no say on where a telescope's going to be pointed. They're just looking at the same data, but for a different reason. So it's not ideal. But again, yeah, telescopes are kind of hard to come by. Even with all these limitations, scientists were generating a lot of information that they needed to sift through. Radio telescopes pick up a lot of noise, and there may be signal in that noise. I mean that signal might be incredibly weak, but you have to really examine the data closely in order to figure out what is truly a signal versus just random noise in the background. And then you have to weed out all the other stuff like did that signal come from a natural phenomenon? Did it come from a terrestrial source. This is not easy to do. Scientists were already having to work pretty hard to secure time with radio telescopes. It would be even harder to secure time with something like a supercomputer because supercomputers also are owned by just a few different universities and research organizations and labs, and they typically are being used for other stuff that takes a higher priority than searching for extraterrestrial and dilligence. And then there was a breakthrough, and that breakthrough came in the form of network connectivity. In the early nineteen nineties, the mainstream public first began learning about this weird thing called the Internet, and by nineteen ninety nine, the Internet was, if not a household term, at least something most folks had some experience or knowledge of. And that's what opened up the opportunity for SETI at home. I'll explain more in just a minute, but first let's take another quick break, So there are many different models for computing. When I was growing up, I was familiar with a more centralized model. So in my case, I was growing up in the era of personal computers, and the computers I first used were completely self contained. They didn't connect to a larger network. All the processing capability, all the programs, all the capacity for storage were connected to the physical computer itself. They might be peripherals, but it was all part of the personal computer. A few years ago, the big trend was cloud computing. So with cloud computing, you've got networked servers that are doing a lot of the processing power for big applications. The devices we're using, whether they're computers or mobile devices or sensors or whatever, are mostly acting as transmitters and receivers for many tasks. We provide input to these devices, and the device then transmits commands to some distant group of servers that takes that information, does some sort of operation on it, produces some sort of result, and sends that back to us. So no longer do we have to have really powerful computers directly at our disposal. We can rely on cloud services to do that computing for us, at least for some things. For other things like if you want to do low latency, high graphics fidelity gaming, for example, you want to have a really good, strong computer processor at your disposal because latency with transmission can completely ruin that experience. But for the most part, you get what I'm saying well. SETTI at Home was an example of sort of a third model called distributed computing. The idea was that you could take a group of regular old personal computers, the kind that any average person could have in their home. You would install some software on those computers, and that software would allow the computers to process chunks of data in some particular way before sending the results back to wherever that data was coming from in the first place. So if someone needed to tackle a really big data processing job, one that could be divided up into smaller chunks, that person could use a centralized computer or maybe a network of computers to send out these smaller unks of data to this distribution of personal computers for processing and then wait for the results to come back, and then group them all together and see what you got. It speeds things up considerably. It increases the processing assets of the project. As more computers joined that project and it reduces the need to turn to stuff like supercomputers, and it also achieved another goal which the founders of the project had in mind, which was to encourage enthusiasm and excitement around the subject of science. Computer scientist David Gedge, astronomers Woody Sullivan and Dan Wertheimer, and David Anderson, who was David's graduate school advisor, collectively came up with this idea all the way back in nineteen ninety nine, specifically with SETI at Home. They were trying to come up with a scientific application people would be excited to participate in, and while they weren't necessarily super optimistic that SETI at Home would produce incredible results from a scientific perspective, they thought from a motivating perspective, it was just the ticket, and it was pretty genius. Upon launch, anyone with a computer and an Internet connection could conceivably help in the search for extraterrestrial intelligence. The researchers created a screen saver program, so if you wanted to participate, you could download the screen saver and install it on your personal computer. When your computer would go idle and activate the screen saver, the processor of your computer, which otherwise would be doing very little would get to work on some data sent over from the SETI research project. So the research project would pull information from a radio telescope divided into chunks and then parcel it out to people participating in this project when complete, when your processor was done working on chunk of data, it would send the results back to the central point for the project and wait for the next chunk of data. And if you were to come back to do some work on your computer, let's say you come back after taking a break for half an hour, the screensaver goes inactive and the program would surrender your processing cycles back to you, so you didn't have to worry about SETI at home suddenly taking up all of your computer's processing power. It would only jump back onto the job when your computer went idle again and your CPU had availability. Now, as I said, this idea was genius, but the original implementation of the idea was less. So now that's not a slight on the researchers, because when they launched the project in May nineteen ninety nine, they were expecting that they might get as many as a thousand people signing up. They figured that, well, this is an interesting idea and we'll probably see some folks really you know, who are really into science join, but I'm not sure about anything beyond that. Now, with that expectation, they only dedicated a single desktop PC for the purposes of assigning processing tasks and receiving the results from the distributed computers. They did not anticipate how enthusiastic the reception to the project would be. They didn't see a thousand people sign up when they launched SETI at Home. They saw a million people sign up. So let's put that into perspective. Let's say you've set up a lemonade stand and you did some brief scouting work and you anticipated that the location you're setting up in you're gonna see maybe ten customers in thirty minutes, and you think that's manageable. Well, what you didn't realize is that you've actually set up your stand in sourpuss scurvy town. It's a town populated entirely by people with an unquenchable thirst for lemonade. So instead of ten people showing up in that first half hour, ten thousand people mob your lemonade stand. You are overwhelmed. Well, the same thing happened to the SETI at Home PC that was in charge of sending out and receiving all that data. It was a good problem to have, but it was still a problem. Sun Microsystems jumped in and donated a bunch of computers to help the SETI at Home administrators make the system work, and from that moment on the program went into high gear. People in the program were contributing to scientific exploration just by allowing their idle computers to focus on complicated mathematical problems when the computer was otherwise not in use. It was a beautiful thing. The response also meant that the project could go through information orders of magnitude faster than if it had all been handled in house. They had the advantage of a million processors. That's something that no SETI project could have afforded on its own at that time. It also inspired other scientific projects to launch distributed computing efforts. Folding at Home, for example, taps into idle computers to solve protein folding problems that could lead to incredible advances in medicine and biology. On top of that, online communities formed around SETI at Home. People connected over forums and formed friendships. There were even stories about people meeting online, falling in love, and getting married out in the real world, all while using their computers to seek out evidence of intelligent life. It was all really remarkable and beautiful. But hey, if it was so super cool, why the heck is the project shutting down now? Twenty one years after it launched? Is the book closed on extraterrestrial intelligent life? Are we done? Have we given up? Well? Not quite. The problem now is that we've got a ton a mountain of processed data from this project that has to be further analyzed, and that taps into something else that I plan to talk about more later on this year, the challenges of big data. We're able to collect mind staggeringly huge amounts of information, but understanding and using that information is another matter. It presents a really big challenge. Even with all of these analyzed chunks of info, that data still has to be processed to see what's actually been found over the two decades of SETI at Home. The researchers overseeing SETI at Home hope to publish a paper on the subject, and to do that they need to look at all the results of the stuff that the program actually found, and so they needed to stop gathering data. While that happens, they have to actually stop so that they can see what they have, as opposed to continuously adding to that pile. This hiatus will allow the team to look at the results, form conclusions, and write a paper based on the whole project. And while we don't anticipate any reports of intelligent communications popping up as a result of this analysis, the endeavor as a whole has been really successful, particularly in the context of getting people excited about participating in science. On the back end of SETI at Home is an infrastructure that grew over time. It is called the Berkeley Open Infrastructure for Network Computing. This support system hosts numerous distributed computing projects that work on the same basic principles as SETI at Home. It's just that each of these projects have a different goal or purpose. Some are dedicated to detecting and measuring asteroids. Some provide cern processing capabilities to help analyze data produced by the Large Hadron Collider in an effort to gain a deeper understanding of particle physics and quantum mechanics. There are projects that focus on climate science, physics, cognitive science, and more, and you can check them all out at boink dot Berkeley dot edu, slide projects dot php. That's bo I Inc. Dot Berkeley dot edu. Slash projects dot php. If you want to dedicate some of your computer's idle processing power to solving really interesting problems in science, it's a great way to contribute. You're not even doing anything active, but you are helping, you know, peel back the border of our understanding. We're pushing that boundary further and further out, and you can do it just with your computer's idle time. It's pretty incredible. So, while SETI at Home is writing off into the sunset, at least for a while, anyway, there are still efforts around the world dedicated in full or in part to the search for extraterrestrial life. The search hasn't ended yet, even if SETI at Home is, at least for now over And while we don't have anything jumping out to us as a positive appslcely yes, we need to check this out. We're pretty sure someone's talking to us. Kind of incident. It's good to remember that space is really big. Who knows, maybe the next star we point a telescope at will be beaming whatever the alien version of the Great British bakeoff is one can only hope, and that wraps up this episode of Tech Stuff. My hat is off to the SETI at Home crew. I think it was an admirable use of technology to inspire people to get into science. I think it was a worthy endeavor to search for extraterrestrial intelligence. It was great to see other projects take that same model and apply it to their own scientific endeavors. So it's to me one of those great stories in technology. Even if we didn't find any direct evidence of little green men out there, who knows what the future will bring. If you enjoyed that episode from March eleventh, twenty twenty, SETI Not at Home, I will be back next week with all new episodes. I miss you guys so much. Trust me. Every time I'm getting my picture taken with Mickey Mouse or Rapunzel or Aeriel, my two favorite princesses, I'm thinking of y'all and wishing you could all be there to be in a big group photo with me. Maybe someday we'll organize a big Tech Stuff trip to Disney World and I'll talk all the way through the Haunted Mansion ride until they tell me to leave, until then I hope you're all well, and I'll talk to you again really soon. Tech Stuff is an iHeartRadio production. For more podcasts from iHeartRadio, visit the iHeartRadio app, Apple Podcasts, or wherever you listen to your favorite shows.