TechStuff Classic: How the Kepler Telescope Works

and it published on June eighth, twenty sixteen, Enjoy. In May twenty sixteen, researchers with the Kepler Mission at NASA held a press conference in which they announced the largest number of exoplanets verified ever at a single event, and that was one thy two hundred and eighty four verified exoplanets. Previously, from two thousand and nine, up to that point, the mission had identified and verified nine hundred eighty four planets. So this is announcement was more than doubling the number

of exoplanets verified. That's incredible. So an exoplanet, just in case you don't know, is of course a planet that is orbiting another star, not the Sun. So it's planets in other star systems, solar systems that are light years away from us. And it was a really cool thing to hear about all these different exoplanets that had just been verified. What I thought was hilarious was leading up to this announcement, you had several news outlets that were

guessing what was going to happen. It was just it was just complete throw stuff against the wall and see what sticks. And there were quite a few that had guessed that NASA was going to announce that the Kepler mission had somehow discovered alien life. Now, once you hear how the Kepler telescope works and what it's meant to do, you'll understand that's really not in the purview of the

Kepler telescope. It is looking for planets that could potentially support life, but it doesn't have the capacity to actually detect life on those other planets unless someone sent aliens to Earth and they started messing with the Kepler telescope, in which case you could say it discovered life, but not through its primary mission. That did not happen. As far as I know, no aliens have been messing with

the Kepler telescope. So let's talk about how this telescope works and this new verification method that the research team used to identify so many exoplanets. What was it that sped up the process so dramatically as to more than double the number of confirmed exoplanets. Plus i'll talk a little bit about the new candidates for Earth like planets that might be capable of supporting life. So first, let's

go way back. The Kepler Telescope is named after Johann Kepler, an astronomer of the late sixteenth and early seventeenth centuries. That's not the original name of the telescope, by the way, but more on that in a little bit. So Johann Kepler is most famous for discovering the three major laws of planetary motion, although at the time no one called them laws. It would take Newton and Newton's observations before

that really started to become a thing. But law number one is that the planets move in elliptical orbits around the Sun. Law number two, the time it takes to traverse any arc of a planetary orbit is proportional to the area of the sector between the central body, for example,

the Sun and the arc. So you can think of the two points along the ark, the starting point and the endpoint of the arc as your barriers on one side, the Sun being the third point in what's not exactly a triangle because you have a curve line a straight line on the arc side the area within that that

is proportional to the time it takes to traverse that arc. Essentially, what that tells you is that the further out you are from a star, the slower your orbit is going to be, and the closer en you are to a star, the faster your orbit is going to be. Also, there's a relationship between the square of a planet's periodic time and the cube of the radius of its orbit, which

is also known as the harmonic law. That's law number three. Now, the Kepler mission all started out with a question, which was how frequent are other Earth sized planets in our galaxy the Milky Way? How common is that? Is the Earth a strange outlier that is one in a billion or one in ten billion, or even more rare than that We had no way of knowing. Now, that particular space based telescope, the Kepler telescope, tries to answer this

question by looking for planets what is called the transit method. Now, this method was proposed a few times leading up to nineteen seventy one, when Frank Rosenblatt really went strong with the idea. He suggested the transit method for detecting satellites orbiting other stars. And technically, the way this works is that you look at a star and you measure the amount of light coming to Earth from that star, and you look for any variations and that any dimming of

that light. Now, if a planet were to pass between that star and the Earth, you would expect the light from that star to dim a tiny amount, and that if you were able to detect that difference, and you were able to observe that this happens regularly over the course of a given amount of time, you could come to the conclusion that what you have seen is in fact a planet passing between its host star and the Earth. This is what we call transit when we see from

our perspective a planet crossing its star. Now we're looking at the planet making its progress across its star in

the course of that planet's year. So if it's close to the same distance from its host star as the Earth is from the Sun, you have to wait a long time to verify that that in fact is what you saw, especially if you want to truly verify it and get a few periodic instances of that dimming, and if it has if it's a start that has multiple planets alone that same orbital plane, then that's going to

cause some confusion too. But by seeing the amount of light that has been dimmed, and by detecting how long it takes this dimming to change back to normal, you can start to make some conclusion like how big the planet must be, how quickly it travels tells you a bit about its orbit. It tells you also by that orbit,

how close it is to its home star. As long as you know information about the home star, then you can start to make guesses as to how hot the planet is or how cold it might be, And this is how you start to draw some conclusions about the

nature of that planet. Ultimately looking for planets that are similar to size, similar to Earth size, i should say, and similar to distance from its host star as the Earth is to the Sun. The reason for that is we know that if the planet is about two times the size of Earth or smaller, it's probably going to have gravity that is amenable to life as we know it. It's going to probably be a rocky planet as opposed

to a gas giant. That's also important. It's probably going to be at a temperature that will allow liquid water to be on the planet, and since life as we know it depends upon the presence of liquid water, that's what we're looking for. Keeping in mind that there is the possibility there could be life out there in the galaxy that doesn't depend upon liquid water. But we have a sample size of one planet with life on it, so we have to draw our conclusions based upon the

limited information we have. So assuming that water is in fact necessary for life, we need to find other planets that could potentially have water on them. So that's kind of guiding the principles behind looking for planets through the transit method. But it's really really hard to do. Now, let's get back to Frank Rosenblatt for a second. He wasn't just famous for suggesting this astronomical approach. He wasn't

known as a great dronomer. He was actually better known as a leading expert in the field of artificial intelligence, particularly in the areas of recognizing visual patterns and speech recognition.

So that was his specific forte. He was really working with computers so that they could recognize visual patterns, they could recognize when what you are saying when you talk to them, and these are fields that today are really coming into their own with stuff like Google's Deep Dream, where it starts to recognize patterns even if patterns aren't really in the picture. It really enhances that and looks for patterns in the in ways that are really interesting

and trippy. And speech recognition, which we're all using to some degree these days, often with the personal digital assistants that are popping up all over the place. Now here's the problem. Rosenblatz suggested approach was not practical at the time in the early seventies, the technological sophistication necessary to detect and analyze such a very tiny change in a

star's brightness. If we were looking for an Earth sized planet at a distance similar to what Earth is from our sun, we're talking about a reduction of one ten thousandth the brightness of a star, and that dimming lasts between two and sixteen hours, So that's not a lot of time, and it's certainly not a big difference in brightness. You have to have a very sensitive instrument in order to be able to pick that up, and that just

didn't exist in nineteen seventy one. Now, we also have to keep in mind that stars tend to be much much bigger than planets. For example, the Sun's diameter is one hundred and nine times greater than the Earth's diameter, and because of that, that's why with the distance is involved and the size is involved, it's such a tiny change in the brightness of the star. However, NASA began to explore how they might be able to use the

transit method to detect exoplanets in a practical way. Back in nineteen eighty four, they were essentially laying out the requirements necessary to detect planets with a reasonable amount of confidence. A conference that they held on High precision photometry acted as the launching ground figuratively speaking, for discussions about a

space based telescope designed to detect a transiting planet. The idea being that in space there would be less noise in the signal to noise ratio, you could get it outside the atmosphere. The effects of the atmosphere would not be an impediment to a space telescope, and it'd be more likely to pick up something as tiny as this

change in brightness. I'll be back in just a moment to talk more about how the Kepler telescope works after this quick break, So in nineteen ninety two, NASA proposed new missions to look into the possibility of life in our galaxy, and the first concept that came up with was called the Frequency of Earth Sized Inner Planets or FREZIP FRSIP, but that proposal was rejected largely because there was doubt at the time that our technological sophistication had

actually reached a level sufficient to detect any transiting planets of Earth like size. So, in other words, if we had gone forward with it, we would have built a tool that was not up to the task of actually doing what was supposed to do, and we would have wasted millions of dollars in the process, not something NASA

could easily afford to do now. Two years later, in nineteen ninety four, a team proposed FREZIP again with a space based telescope in lagrange orbit, but again a committee determined the price would be similar to that of the Hubble, which was incredibly expensive and also had been a black eye on NASA because when the Hubble launched, it launched with a defect that later had to be corrected in space.

A team had to be sent up to make some tweaks to the Hubble space telescope, so that it would perform more closely to what it was supposed to do because one of its mirrors was not right at any rate, they didn't want to involve a you know, or didn't want to invest in a big time project that was unproven, especially after the Hubble issue, so they rejected the proposal.

By the way, in case you're wondering what a lagrange orbit is, that refers to five specific orbits around the Sun. In two of the orbits L one and L two, a spacecraft would orbit the Sun either just inside the

Earth's orbit or just outside the Earth's orbit. So, in other words, if you were look top down, you would have a spacecraft that would be just inside of the Earth orbit moving at the same speed, or one just outside the Earth orbit moving at the same speed as the Earth around the Sun. And you might think, well, how is that possible? Because earlier you mentioned if you're closer in to the star, you move faster, and if you're further out from the star, you move slower. So

how would a spacecraft keep up with the Earth. The answer is gravity. Earth's gravitational pull would be enough to hold the spacecraft in that orbit, that lagrange orbit, and you could do this. You might want to do this for lots of reasons. If it's on the inside of the Earth's orbit, you could do it to study the Sun as it faces Earth. If you did it outside the Earth's orbit, you could look away from the Earth out into the outer Solar System and not have the

Earth in the way when you're studying those planets. There's also another one. L three Lagrange orbit is on the opposite side of the Sun from the Earth, essentially following more or less the same orbital path as the Earth. This is a great way to see the far side of the Sun while the Earth is in its normal location, So if you wanted to study the far side of the Sun you could do that and look for solar activity. Then there's L four and L five, which are sixty

degrees separated either before or after the Earth's orbit. But enough about that. Those are the Lagrange orbits. The idea being that when you place something in there, it tends to be pretty stable. But NASA had determined that putting something into one of those orbits would be really expensive, so eventually they came to the conclusion that perhaps they would want to just put the Kepler telescope in an orbit around the Sun in its own orbit, not a

lagrange orbit. Meanwhile, engineers started to experiment with charge coupled device sensors to see if they could be made to detect tiny changes in light, and lab experiments with CCDs proved that they were a pretty good candidate for this. So let's talk about CCDs for a second. They're designed to move an electrical charge, typically in a way that allows a device to convert the electrical charge into something else,

like a digital value. And CCD image sensors are important in digital imaging, particularly for highly sensitive imaging, such as with very low levels of light. Now you can find digital cameras with CCDs, but many also use or rather instead they'll use active pixel sensors or the SMOs se moss CMOS sensors. And it used to be that there was a noticeable gap in quality that CCDs were demonstrably

much higher quality than sea moss sensors. These days, that gap is much more narrow, it's not as blatant as it used to be, so we've seen the technology of one start to catch up to the technology of the other. Within the CCD you have millions of tiny light sensitive squares called photo sites, and each photo site corresponds to an individual pixel in the final image. It uses the photoelectric effect to turn photons into electrons. That's actually an oversimplification.

It really uses photons to energize electrons push them into higher energy bands, and that is the key to how CCDs work. Essentially, photons raise the energy level of electrons from low energy valence bands to high energy conduction bands.

And each photo site has a positively charged capacitor when the photon converts that electron when it adds that energy to an electron, the electron is then attracted to the positively charged capacitor and the number of photons that penetrated the CCD affects the voltage that this creates, and that voltage is then converted into a digital signal. The whole array is actually cooled through a series of heat pipes that run through an external radiator, so they're actually ratiing

the heat directly out into space. So as this generates heat, they just vent that off into space and it keeps the whole thing cool enough for it to operate without overheating and causing any problems. Now, in nineteen ninety six, two years later. So remember this was first proposed in ninety two and rejected, ninety four, rejected, ninety six, proposed again, and at this point they started to make some changes. One of those was decided to put the telescope into

a solar orbit rather than a lagrange orbit. It was also the point where they renamed the project Kepler, after the astronomer we talked about earlier. But this proposal was also rejected. This time is because no one at that point had proven that a telescope could simultaneously observe thousands of stars. One of the big selling points of the Kepler telescope is that has a very wide field of view and can keep an eye on one hundred thousand

stars simultaneously. But NASA budget overseers were saying, no one's proved that you could do this yet, so researchers went to work on a prototype photometer to prove it could be done. In nineteen ninety seven, they had finished building that prototype photometer, and in nineteen ninety eight they demonstrated that it could observe six thousand stars in a single field of view and generate data that could then be analyzed the results of this project were published in a

paper in nineteen ninety nine. So nineteen ninety nine, seven years after the initial proposal, it's proposed yet again, and it got rejected yet again. So why was it rejected this time, Well, it was rejected on the grounds that there was no evidence the photometer would be precise enough to find Earth sized planets that could also operate in

orbit in the presence of noise. So now the argument was, all right, you've shown that it's precise enough to detect a planet, but maybe not an Earth sized one because those are particularly small. They're not the size of a gas giant, so we need to prove that, and we aren't sure that if you're in space, you will be able to differentiate a planet passing between Earth and its host star or just some random piece of space debris

that happens to pass between a star and Earth. Until you can prove that, we're not giving you any monies. So the engineers built another test bed and they prove that the Kepler telescope could operate satisfactorily even within noise, that their analysis would be able to differentiate between false

positives and the real thing. So two thousand rolls around and the Kepler gets proposed one more time, and this time it's selected as one of three proposals out of a total of twenty six to compete for NASA approval. So it then goes on to compete with these other two projects. And essentially this is the way NASA works. They have teams proposed different potential missions, and then they whittle that down to a group of finalists and then they say fight it out, convince us to fund your project.

And sometimes only one project gets funded. And that was the case for Kepler, and in two thousand and one it won the right to be funded. It became Discovery Mission number ten. So the Kepler Telescope is a discovery

spacecraft by that definition. The actual work on the mission began in two thousand and two, and that started with orders placed for the detectors for those CCDs, and the telescope was completed and lawnlaunched, and it was launched on March six, two thousand and nine, and went into space around its solar orbit. So here's some stats about the Kepler Telescope and the Kepler spacecraft. The diameter of the photometer is just shy of a meter. It's point ninety

five meters in diameter, which is about three feet. The camera has a ninety five megapixel array. So your typical smartphone has an eight to maybe thirteen megapixel camera on it. This one is a ninety five megapixel camera, and it can continuously monitor the brightness of more than one hundred thousand stars simultaneously. The field of view is thirty three thousand times greater than that of the Hubble Space telescope, so it's looking at a pretty wide range of space.

Keep in mind, the Milky Way Galaxy has one hundred billion stars in it, so one hundred thousand is nothing. It's it's a tiny little drop in an enormous bucket. Let's talk about the spacecraft though. The Kepler spacecraft is two point seven meters in diameter, that's about nine feet. It's four point seven meters tall, that's about fifteen point three feet, and it weighed one thousand and fifty two point four kilograms or two three hundred and twenty point

one pounds at the time of launch. Why is it just the time of launch, Well, part of that weight was taken up by fuel hydrozene propellant, which it has used some of since it was launched, there was eleven point seven kilograms of fuel at that point, so that makes a difference. Also the fact that it's in space hard to weigh things. In space. You can talk about mass, but weight not as relevant. It generates electricity with one hundred and nine point eight square feet or about ten

point two square meters of solar panels. Now those solar panels can provide one thousand and one one hundred watts of electrical current. The spacecraft also has a twenty amp hour lithium ion battery that's a rechargeable battery, so when it's generating excess electricity, it charges the battery and everything

can continue to be powered. Once it launched, it became part of the Exoplanet Exploration Program Office, part of the Jet Propulsion Laboratory, so it's been shifted from one group in NASA to another one to actually manage the mission.

So basically, the way the Kepler works, it has more than one hundred thousand stars in its view and it can detect these very tiny fluctuations in the light from those stars, and typically, up until recently, we just had to keep those stars under observation for a really long time to see if that fluctuation would repeat at regular intervals, and it wasn't just something passing between us and the star. And that was how we would go from a signal

that was a potential planet to a verified planet. It also explains why, over the course of several years we were only able to verify nine hundred eighty four exoplanets, with a whole bunch of candidates that maybe are exoplanets but were not sure, so he can't call them that. But then you had this make tenth announcement of one thousand, two hundred eighty four exoplanets. So what changed? How could

we potentially do that? They actually the researchers had analyzed four thousand, three hundred two potential signals these candidate planets, and out of those four thousand, three hundred two they decided that one two hundred eighty four should be verified as actual exoplanets because they had a greater than ninety nine percent certainty that they were in fact planets and not some anomaly or impostor, as they called them. This is pretty phenomenal, right, This is the fact that they

could more than double them. They also had said there were another one than three hundred twenty seven signals that have a better than fifty percent chance of actually being a planet, but those would require more research and observation before NASA would go so far as to say, yeah, here are some These will also join the list of verified planets. They had a very high threshold to call a signal a planet. It had to be greater than

ninety nine percent certainty. So that's pretty incredible, much higher standards than I have. I'd be cool with sixty percent now as a throwbag. The first Earth sized planet that Kepler telescope found in a potential habitable zone, also known as the Goldilucks zone was Kepler one to eight six F and the Goliluck zone that's what we think, that's the band of orbits we think would be would be amenable for life to exist, for water to exist in

liquid form. The Goldilock zone is dependent upon lots of staf like the not just how close you are to the host star, but how old is that host star. You know, if it's an older star that's burned out a lot of its energy, it's a cooler star. So you have to be closer to the to the star in order to get enough energy to support life. As we know it, so it's depend upon a lot of factors. In the case of Kepler one eight six F, the host star is older than our sun, it is more red,

and it's cooler. And this also means that if there is in fact life on Kepler one eight six F, it probably looks different from life on our planet. It's receiving a lot of red wavelength photons coming in, which could mean that the plants themselves might look very different. They might be big red plants all over one eight six F, or it could be a barren wasteland. We

don't know. We have no way of telling yet. We can just make some guesses based upon the age of the star, the size of the star, the distance that we estimate the planet is from that star, those sort of things. Those are the kind of things that we can kind of start to draw some basic guesses around, But they're still gases until we can develop some other

means of really looking at these distant planets. Got a little bit more to say about the Kepler telescope and how that sucker works, but before we do that, let's take another quick break. Now, out of all the one two hundred and eighty four planets announced by this research team. Nine of those are considered potentially habitable, meaning that they are relatively the same size as Earth or no greater than two times the size of Earth, and within their

host stars Goldilocks zone. Now what's really cool is to look at how they determined this, Like what was the way that they verified these planets? And they used a probabilistic approach, meaning what is the probability that any given signal is in fact a planet. Essentially, they were looking at two main factors. How much does a single transit signal resemble what we would expect from a transiting planet, so does it look like what a planet would look

like when passing in front of a star. And then also, what is the likelihood that that particular signal could have been caused by an impostor? And you take these two ideas into account and you try to figure out what is the likelihood that we have and a real legitimate

hit here. One of the people associated with this mission, Timothy Morton, who's in a research scholar at Princeton University, calculate the probability that any given transit signal is actually a planet by using this and essentially you've got numbers between zero and one, and only the results that were as close to one as possible ninety nine percent better than ninety nine percent in fact, were kept and verified

as a planet. Now, the big advantage of this approach is that it can be applied to many signals simultaneously. Instead of having to continuously review the data of a single signal and look for those replicable results, you could take this approach and apply it across multiple planets all at the same time and see which ones come out

at greater than ninety nine percent certainty. Or, as Morton said, if you drop a few large crumbs on the floor, you can pick those up one by one, but if you spill a whole bag of tiny crumbs, you're going to need a broom. And the statistical analysis approach is

their broom. So we've got out of all the different planets found about five hundred and fifty of the two hundred and eighty four that were announced on May tenth, about five hundred and fifty of them might be rocky planets like Earth, and out of those, only nine are considered to occupy the habitable zone. And you might think, well, that's a really small number nine. How many were there before? The answer was twelve, so there were a dozen discovered

before this announcement. Nine more added to it, for a total of twenty one. There are several others that are possible candidates for rocky like planets that could be in the Goldilock zone, but they don't meet that criteria of ninety nine percent yet, so they have not been verified. There's just been twenty one verified planets that are of rocky most likely anyway rocky consistency and in that Goldiluck zone. So this is also we got to remember based on

that assumption that liquid water is a necessary prerequisite. If it's not, then obviously we could be looking at lots of different plants that could potentially support life, might not be life that we would recognize. However, so the kepler, as awesome as it is, cannot detect all the exoplanets orbiting stars. If the planet's orbit isn't at the right angle from our perspective, From the kepler's perspective, it won't

detect any dimming. In other words, if there's a planet crossing that star, but it's at an angle that does not go in front of the star from our perspective, the star doesn't dim, we don't see any change in that, and the kepler can't detect it. So how many plants are actually passing at the correct angle for Kepler to

detect them well. The probability of such a thing is determined by the diameter of the star divided by the diameter of the orbit, which, for a planet the size of Earth orbiting a star similar to the Sun eventually gives you a point five percent chance of detecting that signal. Of being at the right angle to detect that signal point five percent half a percent chance of detecting the

signal in the first place. Bigger plants have a better probability because they are more likely to at least pass over a star partially dependent on you know, they have fewer angles where you won't see anything at all, So a much bigger planet like something like Jupiter could be closer to a ten percent chance. So it's entirely possible, and even probable in fact, that what we have detected is just a tiny fraction of what is actually out there.

Even just with the one hundred thousand or so stars we've looked at, more like one hundred and fifty thousand. But even though we've looked at one hundred and fifty thousand stars and we've detected so many of these exoplants so far, there could be a lot more that we just can't see because of the angle. And then you take into account we're looking at one hundred thousand out of one hundred billion, and the mind really starts to boggle.

We realize that the frequency of planets around other stars is much greater than we anticipated, and that we even may be looking at more planets in the Milky Way than there are stars. So if you have one hundred billion stars and there's more than one hundred billion planets, you think, Wow, the odds of the chances that there is another planet within our galaxy that could potentially support life are pretty good. It may not be anywhere close

to us. It may be on the other side of the Milky Way galaxy from where we are, but the chances are pretty good that there's at least some other planets within our own galaxy, let alone the universe, which is filled with billions of galaxies. And suddenly you think there's no way that we're the only life forms in the universe. That's just not statistically plausible. Is it possible? Well, I mean, technically I guess so, but it's certainly not plausible.

It's more likely that there's life on lots of other planets. Whether it's evolved life that is intelligent, that's another matter. Whether it's life that is anywhere remotely close to us where we would ever have an opportunity to discover it through communication, that's highly debatable. It's quite possible that any life that's that advanced is so far away from us that we haven't had enough time to pass for any

communication generated by that civilization to get to us. Because remember that stuff has to travel at the speed of light. That's as fast as you can go barring some huge change in physics, and so if you are thousands of light years away, it's going to take thousands of years from the generation of a signal for it to get to its destination. And by then the milk has gone bad, and that shopping list that the aliens gave us is not really going to do anyone any good. The party

is over. But still it's really exciting to think about what the Kepler telescope has done. Now, keep in mind, this is very different from other types of telescopes. There

are other ways of detecting the potential for exoplanets. One of those is to look at stars and look to see if they are moving at all, like if there's a little jiggle, which could indicate that there is a gravitational pull upon that star, and that in turn can indicate that there is a planet in orbit around the start and the planet's gravitational pull in the star is causing it to move just a little bit, and that

we can detect that. That's another way of detecting at least the potential of an exoplanet in that star's orbit,

but it's different obviously from the transit method. And then there are ways where we can look at planets to try and determine what are they made of, and we usually use spectroscopy for that, where we take the light reflected off of a planet and we analyze that light and we break it down into the various wavelengths, and then we start to make very educated guesses about the types of elements that are present on that particular planet.

Even so, this is still largely working from very educated guesses, so educated that you could argue they are as good as fact at least in some cases, but you have to keep in mind there's still a tiny room for error. So that about wraps it up for the Kepler Telescope. It has served us well. Its primary mission is over. We will continue to look at the data from the Kepler telescope for many more years, but the actual data

gathering portion of the Kepler's life is over. There are other telescopes that we're playing on launching that will continue this work. It'll either be looking for similar planets to what Kepler was looking for or different style planets. But we're just getting started, and the hope is that we will eventually be able to draw some very firm conclusions about the presence of life within our galaxy, and this

could just be the first step toward that. So while a lot of those news outlets were perhaps being a bit optimistic about the announcement of the discovery of alien life, it is true that this is a step toward making such a discovery, and it may be many, many, many more decades before we're able to say, yes, we've detected the presence of life on another planet. But it's through

work like the Kepler mission that we'll get there. So this is a really cool science and technology story, and I just wanted to touch on that because I love that announcement. I actually listened to it live while they were talking about and it was just really cool to hear a group of engineers and scientists talk about their life's work with such passion. I hope you enjoyed that classic episode of tech Stuff that published on June eighth,

twenty sixteen, about how the Kepler telescope works. I love doing these episodes about telescopes because it's fascinating to me just how they work, how they function, and then on top of that, to learn about the incredible science that we were able to achieve thanks to these instruments. It's really inspiring stuff. If you have suggestions for topics I should cover in future episodes of tech Stuff, there are a couple of different ways that you can let me know.

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