Planetary Radio • Mar 02, 2022

5,000 worlds and counting: the success of TESS

Please accept marketing-cookies to listen to this podcast.

Download MP3

On This Episode

Michelle kunimoto

Michelle Kunimoto

Postdoctoral Associate at MIT Kavli Institute for Astrophysics and Space Research

Bruce betts portrait hq library

Bruce Betts

Chief Scientist / LightSail Program Manager for The Planetary Society

Kaplan mat headshot 0114a print

Mat Kaplan

Senior Communications Adviser and former Host of Planetary Radio for The Planetary Society

Michelle Kunimoto was one of Forbes magazine’s 30 Under 30 in science. Now she leads the most successful search for exoplanets that relies on data delivered by the Transiting Exoplanet Survey Satellite or TESS. She shares this fast-growing catalog of worlds in her first Planetary Radio conversation. Bruce Betts and Mat Kaplan also kick off a new series of great prizes in the What’s Up space trivia contest.

Exoplanet candidates from TESS
Exoplanet candidates from TESS A map of the sky is now crowded with more than 5,000 exoplanet candidates from NASA’s TESS mission. The TESS Science Office at MIT released the most recent batch of TESS Objects of Interest (large orange points on the map) on Dec. 21, 2021 boosting the catalog to this 5,000-count milestone.Image: NASA/MIT/TESS

This content is hosted by a third party (, which uses marketing cookies. Please accept marketing cookies to watch this video.

How to Find Alien Life in a Beam of Light When you look at starlight through a prism, the light separates into a rainbow of color, but some of the colors are missing. This phenomenon might help us one day discover alien life on another planet.Video: The Planetary Society

Related Links

Trivia Contest

This Week’s Question:

What was the name of our solar system’s biggest mountain — Olympus Mons on Mars — before it was given that name? This was back when astronomers only knew it as an albedo or brightness feature on the surface of the Red Planet.

This Week’s Prize:

A stunning, 20 x 36-inch screen print of the Viking Mars lander and orbiter from Chop Shop.

To submit your answer:

Complete the contest entry form at or write to us at [email protected] no later than Wednesday, March 9 at 8am Pacific Time. Be sure to include your name and mailing address.

Last week's question:

Bruce’s Messier Math: What is the number of objects published in Charles Messier’s 1781 catalog multiplied by the Messier number of the Trifid Nebula minus the Messier number of the Starfish Cluster?


The winner will be revealed next week.

Question from the Feb. 16, 2022 space trivia contest:

In 2021, what were the top three professional asteroid survey for near-Earth asteroid discoveries?


The top three professional asteroid surveys for 2021 near-Earth asteroid discoveries were the Catalina Sky Survey, the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS 1 and 2) and the Asteroid Terrestrial-impact Last Alert System (ATLAS).

Viking missions print
Viking missions print A print by Chop Shop illustrating the Viking missions to Mars.Image: Chop Shop


Mat Kaplan: 5,000 TESS worlds and counting, this week on Planetary Radio.

Mat Kaplan: Welcome. I'm Mat Kaplan of The Planetary Society with more of the human adventure across our solar system and beyond. Let me be more precise, TESS, the Transiting Exoplanet Survey Satellite has now found more than 5,000 TOIs or TESS Objects of Interest. Michelle Kunimoto leads the work that has found more of those potential worlds than any other analysis of the TESS data. She'll join us for a delightful conversation in a few minutes. I cannot begin this week's episode without acknowledging the terrible and fast developing news coming from Ukraine. My colleagues at the Society and I are as deeply troubled as most of you are. Casey Dreier and I will open the March 4th Space Policy Edition of Planetary Radio with a discussion of how space exploration and development have already been touched by this tragedy. For example, we learned a couple of days ago that ExoMars, the long awaited Mars Rover from the European space agency and Russia is now likely to miss its already delayed launch this year.

Mat Kaplan: Of course, nothing we will have to say about space exploration can come close to the horror of the destruction, the loss of life and the threat to a thriving democracy we are all witnessing. Our hearts are with the Ukrainian people, even as we look to the sky. Astrophysicist and science writer, Kaitlin Rasmussen has written a terrific article for our website about spectroscopy and how it may someday soon reveal signs of life on a distant world. Some of my colleagues have created a beautiful video that compliments Kaitlin's piece. I liked it so much that I asked if I could share the just over two minute soundtrack with you. Here it is voiced by our digital community manager, Sarah Al-Ahmed.

Sarah Al-Ahmed: When you shine a beam of light through a prism, it turns into a rainbow of color. The prism separates the light into the different wavelengths that make it up, which we see as different colors. If you do this with the light from a star and look closely, something is missing. Atoms that stars are made of absorb light at very specific wavelengths. Those specific colors never leave the star. When star light passes through a prism, the rainbow it produces has some dark patches in it. The colors that are missing tell us exactly which atoms are in the star, what it's made of. This science is called spectroscopy, and someday it might help us find alien life on another world.

Sarah Al-Ahmed: When we look at light from distant planets or the star light that passes through their atmospheres, we can use spectroscopy to find out which atoms and molecules are present on that world. To find life on other planets orbiting other stars, we look for signatures. Certain molecules that are only likely to exist in atmospheres of planets, where there is life. On Earth for example, some of the methane in our atmosphere comes from animals. Methane is a biosignature because the only way it can stick around in an atmosphere is if it's constantly being produced by something.

Sarah Al-Ahmed: If we were to find methane in an exoplanet's atmosphere, we could have our first hint that there might be life on that planet. We haven't found biosignatures on any exoplanets yet, but we're only just starting to look. The more we look at what's out there, the better our chances are of finding alien life.

Mat Kaplan: Wait till you see the video that goes with that soundtrack. We've got the link to it as part of Kaitlin Rasmussen's article on this week's episode page at It's also on The Planetary Society YouTube channel. If spectroscopy finds biosignatures on an exoplanet, it's likely that world will have been discovered by TESS. The Transiting Exoplanet Survey Satellite is operated for NASA by MIT, the Massachusetts Institute of Technology. We've talked about TESS several times on our show, but this will be our first conversation with Michelle Kunimoto. If her name sounds familiar, it might be because she was named by Forbes Magazine in 2017, as one of 30 Under 30 in Science.

Mat Kaplan: Michelle was the youngest of the group by a wide margin. Now she is a TESS post-doctoral scholar at MIT's Kavli Institute for Astrophysics and Space Research. Her deep statistical innovations have led to what she calls the TESS Faint Star Search. It is responsible for more than 1600 of those TOIs or TESS Objects of Interest. Michelle and I met online a few days ago. Michelle, welcome to Planetary Radio. Congratulations on these wonderful findings to not just you, but the whole team that you've been working with and everybody else behind TESS. What marvelous success, this spacecraft and all of you are seeing.

Michelle Kunimoto: Thank you for having me. And I really do feel honored to represent, I'm just one cog in a much larger machine of a lot of amazing researchers and scientists that work around the world to help make TESS be as successful as it is today.

Mat Kaplan: And isn't that usually how it goes nowadays. When I checked a few minutes ago this morning, there were 5,243 items in the Toi or TESS Object of Interest catalog, and I bet by the time listeners hear this show, they're going to be even more. That really is stunning. Does this surpass, or does it meet your expectations?

Michelle Kunimoto: TESS is definitely doing as well as I would've hoped. In fact even more just in the past year alone. This time, last year, we had half as many TOIs and that's just an incredible increase in the number. And I don't necessarily expect that we'll double that a number again by the time of next year, but definitely a 1,000 new planets per year is a really healthy discovery rate and we're finding some incredible stuff.

Mat Kaplan: And I know that you've just submitted another paper, you and some other colleagues that actually looks out, projects the number of planets, exoplanets, or at least candidates that we might expect to see, but I'll come back to that. As you know, Natalia Guerrero, your colleague in MIT was my guest last year, and it was the article that she wrote that connected me to you, and she actually put the two of us together. And I saw that she's a co-author on the December paper that announced this discovery of over 5,000 objects. It's an interesting team that you have.

Michelle Kunimoto: Yeah. Got a lot of different types of expertise. So I'm a postdoctoral associate working on the team. Natalia had been working on the team for much longer than me, so I've really benefited from her expertise on TESS and learned a lot from her as well.

Mat Kaplan: Are you getting better as time goes by at finding these other worlds?

Michelle Kunimoto: Absolutely. Continuously the team that I work on, notice the Quick-Look Pipeline is always making adjustments, making improvements. And one of the big projects that I've been working on is to try to find even more planets from the TESS data that we have on hand. So just as an example, every month, the team that I work on processes data for about a million stars, which is an incredible amount of data to go through in just a single month. Because that's such a large number, we only try to find planets around the very brightest of those stars, which is maybe a few hundred thousands, but that means that there are hundreds of thousands of stars that are left sitting there and we're not looking for planets around them. So one of the main improvements that we've done over the past year was we have better methods and algorithms to be able to sift through that and really identify thousands more planets from that list.

Mat Kaplan: Is this therefore your Faint Star Search about which this paper revolves? The one that came out in December. Did you develop this as part of your PhD program?

Michelle Kunimoto: It grew a little bit off the PhD program. So for my PhD dissertation, I primarily focused on data from the Kepler mission, which was NASA's previous exoplanet finding mission and its first exoplanet finding mission. In my PhD I developed an algorithm that could look through planet search results and try to identify the best planet candidates from that list. And it did so in an automated way, so oftentimes we as humans have this remarkable ability for pattern recognition and will be reviewing a lot of planets with their own eyes. But we have so much time to do that, and it takes a really long time to review even just a few thousands of signals. So how can we handle the amount of data that's coming out of something like TESS, where we have millions of signals in a single month to review?

Michelle Kunimoto: We can't do that all just by ourselves. We need to rely on more automated algorithms to do that. So that was something that I first developed in the PhD and on the TESS team, I've started to improve that and tune it a little bit more towards TESS specifically, that is the Faint Star Search that came out. So far the Faint Star Search has added more than 2,000 TOIs to the 5,000 total number.

Mat Kaplan: Terrific success. Obviously. I'd like to hear more about the actual process and as part of that, maybe you could explain these so-called pipelines, the QLP and another one called SPOC S-P-O-C, which deliver the data.

Michelle Kunimoto: Of course. The basic idea behind finding planets with TESS is we're looking for things known as transits. So the idea is we have a star and as a planet passes in front of that star, it will block a portion of that star's light. Kind of like if you were to look at a light bulb and a moth is flying around it'll block that light every now and then. So if we have a telescope like TESS, that's looking at this star and measuring its brightness over time, every now and then you'll see a temporary decrease in the brightness, and it might last just for a few hours and it might happen once a year. So we have to continuously be looking at these stars, that's what's known as a transit.

Michelle Kunimoto: So the QLP team takes that data, those measurements of brightnesses of stars over time and uses a pipeline to search through that data to look for these signs of transits. There's two different types of observations that TESS takes, one is known as the full-frame images. So these are essentially huge pictures of the night sky that TESS observes. It covers a huge strip of the sky and it takes that data every 10 minutes. So we have measurements for a million or so stars that are observed in the full-frame images for every 10 minutes over a given span of time.

Mat Kaplan: And we've seen some of those beautiful images from those, really it's four cameras, right? Working together staring at one section of the sky.

Michelle Kunimoto: Exactly. So that's known as a sector and after 27 days, TESS will rotate and look at the next huge strip of sky. So at the end of a year, you have this beautiful mosaic of the night sky and it covers so many different stars, so many different areas of the sky. And hopefully by the end of the mission, we'll have observed a 100% of the sky overall.

Mat Kaplan: So QLP, that's the Quick-Look Pipeline, that other one I mentioned SPOC, I saw is Science Processing Operations Center, but it's a separate way of processing this data, and where does your Faint Star Search come in?

Michelle Kunimoto: So SPOC is the official NASA planet search pipeline, and they primarily handle a different observation mode. So as I mentioned, TESS observes the full night sky of the full strip of sky in the full-frame images, but there are much smaller what are called postage stamps, which are basically centered on a given star. And those are recorded every two minutes, so much more data is being observed for these very specific stars. But we have only 20,000 of those that are observed every sector, it's a very pre-selected small list. So the SPOC team takes that data, processes, makes the measurements of the brightness of those stars and then looks for planets around them. So the QLP is looking at roughly a million stars in the full-frame images, and the SPOC team is looking at the smaller and shorter two minute cadence observations for about 20,000 stars. And we're very complimentary in a way, we're both identifying a lot of the same planet candidates, some of us find different planet candidates, and it's a really amazing way that we can collaborate and try to find as many planets as we can.

Mat Kaplan: So stars in the millions, candidates in the thousands and counting, but the number of confirmed exoplanets lags way behind, there's this huge backlog. And I just wonder if you expect that's going to continue because it is so difficult for these ground based telescopes to follow up on the findings.

Michelle Kunimoto: Yeah. That's exactly what it is. A lot of the time we have a lot of information about these planets that is internal, that the follow up community has been able to take, but somebody just hasn't sat down and written a paper about it. So we might even have very high confidence that a given TOI is a confirmed planet, but we still need somebody to decide that, that's a planet they're interested in. They'll write a paper, publish it, have it go through peer review and people will accept that this is a validated planet. So we need not only a lot of follow up, but somebody who has the initiative to do that. Thankfully as we observe more and more stars and find more and more planets, there will be a plethora of attractive targets to choose from. And as the mission goes on, those planets are going to be getting more and more follow up, which will make it easier to confirm them as real planets.

Mat Kaplan: Anybody who looks at the raw numbers, the number of TOIs TESS Objects of Interest, and the number of confirmed planets, will also see what may look to a lot of people like a big number of false positives. Is that a problem or is that just an expected part of the process?

Michelle Kunimoto: It's absolutely expected. Obviously we do our best to try to identify those false positives that can mimic a planet to transit in the data, but there's no pipeline that is a 100% perfect at being able to find all the planets and get rid of all the false positives. Oftentimes there are things that we just need follow observations, TESS alone is not able to tell us whether something is a planet or a false positive, so those false positives are very expected. As we get more data from TESS and we improve our algorithms to distinguish planets from false positives, I expect that false positive rate will get lower.

Mat Kaplan: Here's a question that only occurred to me, what causes a false positive? If it's not a planet, a world transiting in front of that star, is it being caused by some other variability and that star's brightness as we see it, as TESS sees it?

Michelle Kunimoto: Yeah. So one of the most common types of false positives is another star that's actually orbiting the target that we're looking at. So you might think that if a star were to pass in front of our target, it would block a lot more light than planet, which is very small. But what if that star happened to just graze our target star? So it just covers just the very, very edge of that star. It would block only a small amount of light that could look like it's a planet blocking that same amount of light. So these are the most common types of false positives because those events in our data look really similar to what is caused by a planet.

Mat Kaplan: I'm thinking also of some of what I read about how TESS is also now has almost by necessity, I guess, has looked at the area that was stared at by Kepler, that pioneering exoplanet discovery spacecraft, that had a long road to getting out there in space and proving it could make this technique work. You worked with that data as well, that Kepler data originally. We're obviously building on that, and I just wonder you have thoughts about the pioneering work that was done by Kepler.

Michelle Kunimoto: Well, Kepler undeniably revolutionized exoplanet science, and before Kepler 85% of all known planets were larger than the size of Neptune, and we believe that those were clearly the most common types of planets out there. And thanks to Kepler, we now believe that 85% of planets are smaller than Neptune. And in fact, the most common types of planets are those between the sizes of Earth and Neptune. And just that complete change in our perspective of the average planet in the Milky Way galaxy caused the rewriting of planet formation and evolution theories. And that was just based off of a search of 200,000 stars. So one of the great things about TESS is because it's looking at such a large number of stars. In fact, by the end of the seven years, including the upcoming extended mission, that number will be in the tens of millions of stars. I'm just expecting that we're going to be once again, seeing an incredible revolution in exoplanet science. And I feel really lucky to be part of that.

Mat Kaplan: I bet you do. I feel lucky just to be able to talk to you about this and witness these discoveries, but you now get into this other paper that I mentioned. Which was just published a few days ago, as we speak where you actually used some of your statistical techniques and working from the data that already exists to predict how well TESS is going to perform over the next well, the second half of its life. We're about three and a half years into the mission, already in an extended mission, hoping to get a full seven years, if not more, what conclusions did you reach? How many more of these worlds can we expect?

Michelle Kunimoto: There were four motivating questions for that work. The first one was, how many planets do we expect from EM2? The second extended mission, but also what types of planets are those going to be? Are they primarily going to be small planets? Are they primarily going to be big planets? Are any of them going to be potentially habitable planets? And the results that I came away with are after the next three years, so our second extended mission could add as many as 4,000 new exoplanets to our list. And if you take into account all the data that we have so far, the TESS yield could be about 12,500 new planets.

Mat Kaplan: Wow.

Michelle Kunimoto: And we're at 5,000 TOIs, so even with the data at hand, I'm finding that there are thousands of planets that have just yet to be discovered, but because it's such an enormous amount of data, obviously no single planet search team has searched all the data. So we have definitely not extinguished the number of planets that we can find with TESS, even with the data at hand, and we are looking at a really rosy future.

Mat Kaplan: Astronomers are going to be working with this TESS data for many, many years to come, obviously.

Michelle Kunimoto: Yes.

Mat Kaplan: Michelle Kunimoto of MIT and the TESS team will be back in moments here on Planetary Radio.

Casey Dreier: I'm Planetary Society, Chief Advocate, Casey Dreier. Are you interested in our Day of Action to advocate for space, but can't commit to a full day of congressional meetings? Or do you live outside the United States? Either way I have great news for you. You can go to and pledge to take action with us on March 8th. We'll provide you with easy, effective actions you can do on your own time from anywhere in the world. That's Thank you.

Mat Kaplan: I want to hear more about how you developed the Faint Star Search. Actually creating the algorithms behind this and then developing them, refining them. Not that I would be able to understand the higher levels of math involved, but I just wonder if you can say more about the process and the human role, the ongoing human role in this as well.

Michelle Kunimoto: So for the Faint Star Search, just going back to what I said about telltale false positives, so one of the most common being another star that's orbiting our target star rather than a planet. These typically have some telltale signs that we can use to figure out that it's actually not a planet. So one of the examples is planet transits typically have a U shape. So those decreases in the brightness of the star will decrease very suddenly and then have a flat bottom and then go back up and then the light will continue. Whereas a transit that's caused by another star will typically have a very V shape. So it will be much more a gradual slope finishing at a point, and then going back up like a V. So if we can write an algorithm that can calculate, that can quantify that shape as how V shaped is this event, we can say, "We think that it's likely this is not a planet."

Michelle Kunimoto: Yeah, there's a lot of other telltale signs that are similar to that, but essentially what we're doing is we're designing tests that can take a look at the transit shape and the other properties of that transit and spit out a score. So a high score means it's very likely to be a planet and a low score means it's not consistent with planet, it's likely a false positive. The algorithm is determining these scores for a large number of signals and we're looking at the highest scores only.

Mat Kaplan: So in that specific example you gave, it's like teaching a computer to tell the difference between a sine wave and a square wave. Right?

Michelle Kunimoto: Exactly.

Mat Kaplan: So why would a star, a smaller star passing in front of the large star cause more of a curve, a sine wave than a world, a planet would? Is it something about that other star's brightness level? Tell me.

Michelle Kunimoto: So with a planet transit, usually those planets are going to be passing directly in front of the star. So the entire surface area of the planet is covering that star. So if you can imagine you've got this huge disc in the sky that's the star and our little disc is the planet passing in front of it. So because that entirety of the planet is hovering the star that's what causes this U shape. The typical eclipsing binary stars is what they call these false positives is they'll typically just graze the very edge of the star and cause a transit depth that's similar. And because of that geometry, it just happens to give you more of a V shape. So it's really just the orbital geometry of the difference between a central planet transit versus a grazing eclipsing binary.

Mat Kaplan: Can you classify? Do the majority of planets that have been found thanks to your Faint Star Search, do they fall into a particular category in terms of size or distance from that faint star they revolve around?

Michelle Kunimoto: More than half of them have been known as Hot Jupiters. So these are Jupiter sized planets that are very hot. I know it's a creative name, but it means that they orbit really, really close to their stars, so they have very high temperature. These were some of the most common planets that were found early in the exoplanet detection history. So some of the earliest planets found in the 90s were all Hot Jupiters and that's just because they're the easiest planets to find. They have really large radius, so their transit depth are really deep. They have really large masses, so you can find them easily with other detection methods and because they orbit so quickly, you can catch these transits really, really often. So the reason why the faint star search has found so many of these Hot Jupiters is just because when you get to fainter and faint your stars, the noise level of your data is going to be a lot higher.

Michelle Kunimoto: Hmm. It's kind of like if you're in a crowded room and you're listening to kind of the noise level of the room with a lot of people talking when you get to faint and faint, your stars, that noise level just becomes really, really high and becomes harder to hear people talking in the room. So Jupiter size planets, because they have these enormously large transit depths because they're such large planets and they're blocking so much of their stars light. They're speaking really loudly compared to the noise level of the room and they're easier to find around these [inaudible 00:25:16] stars. As a result the Faint Star Search hasn't found too many small planets. It's definitely a minority of the planets are going to be smaller than the size of Neptune. These are primary giant planets, but there's still some interesting things that we've been able to find, and for those people who are interested in Hot Jupiters, this will be a really great sample to look at.

Mat Kaplan: Yeah. They're worthy of study if only because obviously there's so many of them across the galaxy. But what is the outlook for finding, I'll use that term that we use a lot on the show, Earth-like planets that are roughly the size of our own planet and are in that Goldilocks habitable zone?

Michelle Kunimoto: So the predictions by the paper that just came out a few days ago, are that in an optimistic habitable zone. So let's just try to be really optimistic about what is considered the limits to our Goldilocks zone. I'm finding that there should be about 18 planets that TESS will find, that are small than twice the size of Earth, which I'll consider a terrestrial Earth-like size. For a much more conservative limit, so if we try to make the conditions on this planet much closer to the Earth, there are go going to be about nine planets that TESS is able to find. Currently TESS has found six planets in the habitable zone, in the optimistic habitable zone and two planets in the conservative habitable zone.

Mat Kaplan: I'm glad you went with the optimistic scenario first because that's the one I'm in favor of, of course, and I don't have to deal directly with the data. Is this an indication of how rare Earth-like planets are based on these two parameters, size and habitable zone, or is it just a limitation still as sophisticated, as capable as TESS is of our ability to find worlds like our own?

Michelle Kunimoto: It's definitely the latter. Kepler tried to find an estimate for the frequency of Earth-sized planets in the habitable zones. The expectations were that it would find a lot of such planets if they were common, it didn't find as many as we expected. In fact, depending on how critically you look at the planet candidates, Kepler didn't find any Earth-sized planets in the habitable zones. And that's just because these really, really small planets cause such small transit depths because they block so little of their stars light. It would be like, if you're imagining the Empire State Building and all of the lights are on and all the window shades are up and you're staring at this Empire State Building from a 100 kilometers away and somebody closes the shades of a single window by just a few inches and that happens once a year.

Michelle Kunimoto: It's really incredibly difficult to find Earth-sized planets in year long orbits around on sun like stars. Now a benefit of TESS is it's looking at a much wider type of stars. So the habitable zone for cooler and smaller stars is going to be closer in because these are such cooler stars, the planets have to orbit a lot closer to have a similar temperature as their own Earth. Those types of stars are among the most common types of stars in our galaxy and TESS is observing millions of them. But those are also very faint, and that brings us back to the whole faint stars will have a lot of noisiness in the light curves, so it challenges the identification of small planets. So what we're really going to be seeing is as TESS is re-observing a lot of these stars, the yield of these small planets in the habitable zone is going to significantly increase. In fact, from the end of the current extended mission to the end of the next extended mission, the number of planets in the habitable zone is going to roughly double.

Mat Kaplan: Wow. And by the way, kudos for yet another great analogy using the Empire State Building. Nicely done. I wonder about your thinking about what these results are telling us, not so much about the stars where TESS is capable of finding these exoplanets, but the ones where it can't. The ones where those planets are not transiting the surface of their star as we see it from our limited angle here on Earth or nearby. I have to think that it gives us a lot of encouragement for finding planets eventually around a lot of stars, most stars.

Michelle Kunimoto: Yeah. So the probability that a planet transits as seen by TESS for something like an Earth-sized planet around in a year long orbit is about 0.5%. So it's incredibly challenging and difficult to be able to catch a transit. And so the fact that we found 5,000 TOIs at such low transit probabilities, we can extrapolate and that means that the number of planets is actually really, really common. Every star in the galaxy that's similar to our sun has multiple planets around them. And even the nearest stars to our sun must have multiple planets. I think that's actually one of the reasons why one of the planets around Proxima Centauri is my favorite planet.

Mat Kaplan: Ah.

Michelle Kunimoto: And that's because it's the nearest star war sun, so just four light years away. And it hosts a small Earth-sized planet in its habitable zone. So if our nearest star to our sun is able to do that, it just opens you up to the fact that there must be out there.

Mat Kaplan: A statement of faith, but one based on good data. How did you know I was going to ask you if you had favorites? Okay. So there's that one, a great choice. Do you have other worlds that TESS has found that really gets you excited?

Michelle Kunimoto: I'm a bit biased here, but in the Faint Star Search, I did come across a multi-planet system, currently working on a paper that is going to be confirming those planets. And I've got some follow up and what's really exciting about the system is it has three planets, all with orbital periods less than 15 days. And two of them are sub Saturn-sized planets. So these are really massive planets that are in really compact orbits, and it's one of the only type systems that we've seen so far. I won't give the exact name of the system, but there're indications that there might be a fourth planet in this system that TESS didn't see, but we can see because of some extra data we've got. So it's something that I'm really excited about and hoping to finish up that paper soon and be able to present it to the world.

Mat Kaplan: I look forward to hearing about that. Thanks for sharing that preview with us and congratulations in advance of publication. I guess I should ask, what do you most look forward to other than the continued great performance by TESS? Here we have of the James Webb Space Telescope now having its mirrors aligned and a lot of us out here hoping that it does even better at being able to help us understand these exoplanets than some of the scientists, some who we've had on this show are willing to talk about or are willing to hope for even, but what are you looking forward to?

Michelle Kunimoto: That's a really good question. Where do I begin? I think one of the things that I really love about working on TESS is just how available we want to make our data products to the public. I love to see news articles of people in the community who are obviously not officially affiliated with TESS, but they might have high school students, they might be undergraduate students, they might just be amateur astronomers looking for planets with TESS data, with a lot of the resources that we make available. And so I'd love to see more of that in the future, and that's definitely our goal on TESS. I'd also really look forward to... Yeah, I've just got so many ideas. So let's see.

Michelle Kunimoto: I think one of the things that really excites me about TESS too, is it's looking at all types of stars that it observes. Kepler looked at only a very specific type of star, it was mostly G type stars like our sun, but TESS is looking at all types of stars. So that means white dwarfs, it means a lot of M-dwarfs, it means all kinds of other stars. So we don't know how common planets are around those types of stars because Kepler didn't observe any. TESS is already found a planet that's orbiting a white dwarf star. That was just an incredible discovery that we didn't think was even possible. And I'm excited to see more of those really exotic types of planets that we've never seen before, now that TESS is going to be able to uncover.

Mat Kaplan: That outreach activity that you mentioned in that response. That's something that is obviously very important to you. You've been doing outreach since you were at least an undergraduate, right? Why is it so important to you?

Michelle Kunimoto: Yeah. I think general public is my favorite type of audience to talk to because I really just love sharing my passion for astronomy, especially to people who aren't super familiar with it. It really touches on a fundamental question that we've all asked ourselves at some point in our life, are we alone? Is there other life out there? And a lot of people that I talk to are science fiction fans, and they might have gotten inspired to be interested in astronomy because of Star Trek or Star Wars. For me personally, it was Star Trek: The Original Series.

Mat Kaplan: All right.

Michelle Kunimoto: Yeah. And I just find that the general public is just a really fun group of people to talk to because people coming from all types of backgrounds, all types of familiarity with astronomy. And I think the questions that I get asked from the general public it just shows how curious human of beings are, right. They're not here because this is the career path they've chosen, but because this is just a hobby that they really, really are passionate about and they've always questioned. A second reason why I really like doing that is because I'm able to speak to people who might be inspired to go into astronomy or exoplanets in the future, especially young female scientists. So a lot of the talks that I gave, especially as an undergraduate and a PhD student were to first year undergraduates or high school students.

Michelle Kunimoto: And I had amazing feedback from young girls and women who were interested in doing science and they just spoke to how much it meant for them to see a young female undergraduate talking about research and making these discoveries. And it seemed really inspiring to them, so I really felt honored that they would see that in me and that I could be able to be a role model for them. So I really, really value that.

Mat Kaplan: It is so nice to hear this and that you're sharing this passion that you obviously have for your work. And you talked about those two questions, those questions that our boss Bill Nye says, "All of this is so much about where do we come from? And are we alone?" You're still very early in your career, where do you hope to be headed? You've got a good start.

Michelle Kunimoto: Yeah. This is a challenging question. I still don't know yet. Obviously there's a lot of pass forward, I could go through academia. So potentially become a faculty member at a university, or I could perhaps try to see if I could work for NASA or the Canadian Space Agency. I don't know yet, which I would prefer to do. And I think this post doc is the time to really be trying to figure that out over the next year. I think at the moment I'm leaning towards trying for academia. One of the things that I really liked as a PhD student was being a teaching assistant for some astronomy and physics courses, being able to work with undergraduates. Those were some of my favorite interactions and having a bit more of a mentoring and a teaching side of things. So that's something that I'd be able to do in academia as a professor, while still doing a lot of research that I find I'm passionate about. That's my tentative answer, but I might change my mind tomorrow.

Mat Kaplan: It's a good answer. And I sure look forward to seeing your continued contributions in both of those areas. Michelle, thank you. And live long and prosper. I am delighted to have had this chance to talk with you today about great work that you're doing with TESS and how it reverberates across the galaxy.

Michelle Kunimoto: Thank you. Thank you for having me again.

Mat Kaplan: It's time for What's Up on Planetary Radio. Here is the Chief Scientist of The Planetary Society, Bruce Betts, welcome back. I know you're looking forward to telling us about the night sky.

Bruce Betts: Oh, I am Mat. I'm so very excited and excited, I'm excited. Should I tell you things? Okay. So in the evening sky, we've got no planets to look at, but we've got that whole beautiful Orion thing over there in the south. And if you take Orion's Belt, if you go one direction, you get to Sirius brightest star in the sky. But if you go the other direction, you'll get to the Pleiades the faint star cluster, and also above the line you'll get to tall Aldebaran of Taurus. In the pre-dawn however, there is still quite the planet party going on. We've got Venus looking super bright over in the east, in the pre-dawn. Mars, near it looking dimer and reddish and to their lower left, you'd need a really good view to the horizon, but Saturn and mercury are really close. In fact about the time this comes out, the second and third, they're really very close to each other in the sky. Saturn will get higher, mercury will get lower. Saturn will get easier to see right now. Venus, Mars, they're the easy things. There we go, Mat, how's that for the night sky?

Mat Kaplan: I'm thrilled. I would be if I got up that early enough in the morning, but I don't think I will, but yeah, I'm happy for all of you who do.

Bruce Betts: Me too. Let's move on to this week in space history. Speaking of happy, a couple happy things. 1969, Apollo 9 was launched this week. Apollo 9, the earth orbiting test of the lunar module. It was successful, spoiler alert. 50 years ago, this week, the launch of Pioneer 10, the ground breaking first spacecraft through the asteroid belt, first spacecraft to Jupiter and the first spacecraft launch that's one of the five spacecraft leaving the solar system permanently, that was 50 years ago. And I know some point very soon if it's not already up there, there's going to be an article on our website. Nice information page about Pioneer 10, Pioneer 11, so check that out at

Mat Kaplan: Not only that this coming Space Policy Edition, which is just a couple of days away as we speak my regular monthly show with Casey, will largely be inspired by this anniversary by the Pioneer spacecraft. Should be an interesting discussion of deep space exploration.

Bruce Betts: Well, it's cool. I knew that, you know what else is cool? I bet you do. Random space fact. Mercury, it's a speedy little bugger. Mercury's orbital speed is almost nine times faster than Neptune's orbital speed.

Mat Kaplan: Fleet of foot. Well named.

Bruce Betts: Indeed, and it takes longer to swim through the solar system, so Neptune well named or being pulled by a chariot. Still, there's a lot of water resistance. Anyway, that's not important right now. You know what is important right now, Mat? I bet you do.

Mat Kaplan: I do.

Bruce Betts: It's the trivia contest. And I asked you in 2021, what were the top three asteroid surveys in terms of near-Earth asteroid discoveries? How did we do, Mat?

Mat Kaplan: We had a substantially reduced number of entries for this one, but here's the answer from our poet laureate at first, Dave Fairchild in Kansas, Catalina led the league with 1400 plus. Pan-STARRS was next in line in search of NEO dust. I like how we did that. ATLAS comes in number three, with NEOWISE at four. Thanks to them, we will not end as did the dinosaurs.

Bruce Betts: Nice rhymes, nice rhymes and correct answers. Catalina, pan-STARRS and ATLAS being the top three in 2021.

Mat Kaplan: Ken Reilly in the state of Washington recognize that there were a lot of people and teams looking for these objects. He says, "But every team's members and patrons should receive a participation blue ribbon." He said, "As long as humans continue to shove each other out of the path of a leaping omnivore, our future looks positive." Which [inaudible 00:42:22] sort of an anthropological note to that, that I really like. Mel Powell in California, he says, "This one took me down yet another research rabbit hole on a NEO. Who knew NEOS had rabbits."

Bruce Betts: Elmer Fudd.

Mat Kaplan: Yeah. All right. I must have missed that, that Warner Brother's cartoon. Our winner is waiting, waiting patiently. Wait, no more. Esan [inaudible 00:42:50] whose name I am absolutely sure I mangle every time I say it. He did provide us with the Catalina Sky Survey, the Panoramic Survey Telescope and Rapid Response System also known as pan-STARRS and the Asteroid Terrestrial Impact Last Alert System or ATLAS. So congratulations again Esan, by the way, he's in Ontario, Canada, where we have a whole bunch of listeners and supporters of The Planetary Society. Esan, we are going to send up your way in Ontario, Goodnight Moon Base by Brett Hoffstadt, that terrific children's book that newest take on Goodnight Moon, and it is very clever with these lovely illustrations by Steve Tanaka that are very much in the style of the original book that inspired all of these Goodnight Moon. It's available from all the usual places, and it's published by Aero Maestro. I recommend it. In fact, Esan I've got your copy, your signed copy right here in my hand.

Bruce Betts: So these three surveys that find us right now, the majority of NEOS are all a part of the NASA funded professional surveys. And they're what require follow up observations and such from a whole bunch of observatories including amateurs and including the Shoemaker NEO Grant winners that we talked to recently. A follow up on the initial discoveries to figure out orbits and the like.

Mat Kaplan: It's a great species wide effort to save ourselves from that fate of the dinosaurs. To close here is a contribution from Gene Lewin, also in Washington, everyone contributes where NEOS are concerned with surveys scanning upwards, no stone should be left unturned. Some professional organizations' mission to search the skies, Catalina, pan-STARRS, ATLAS, and a reactivated NEOWISE, the first three that are listed in '21, they top the list for discoveries of NEAs. Let's hope that none are missed. These discoveries are important. Let me just tell you, Bob, we may soon be able to divert its path and avoid [inaudible 00:45:11].

Bruce Betts: Very impressed with all of these poems and how they find brimming words for-

Mat Kaplan: I know.

Bruce Betts: Things like that.

Mat Kaplan: Far beyond my capacity. Absolutely. We are ready to wrap this up with a new contest.

Bruce Betts: All right. We're headed to Mars, the largest mountain in solar system. What was Olympus Mons named before being named that back when astronomers only knew it as an albedo or brightness feature? Go to

Mat Kaplan: That's fascinating. I did not know that it had actually been recognized before they realized it was that hulking extinct volcano.

Bruce Betts: It did, as we'll probably hear there were suspicions for various reasons that it was a mountain, but not confirmed until spacecraft got there.

Mat Kaplan: You've got until the ninth that be March 9th at 8:00 AM Pacific time. And we are going to start a new series of really terrific prizes for the winners out there. This first one, in fact, all of them will come from our friends at Chop Shop,, or you can find The Planetary Society store all of our merchandise, but all of his other great stuff, including this week, this Viking print, it's a 20 by 36 screen print. It is absolutely beautiful. I got to say they do the most wonderful designs and it shows Viking, I assume, Viking 1 dissenting to the Martian surface as the Viking orbiter passes by overhead. It might be yours, if you are the winner in this latest contest provided to us by the Chief Scientist, Bruce Betts. And we're done.

Bruce Betts: What? I provided something?

Mat Kaplan: Every time.

Bruce Betts: You have to buy the prize? Oh, the trivia question. Yeah, that is I. Okay. Everybody go out there, look out for the night sky and think about your favorite marine mammal. Thank you and goodnight.

Mat Kaplan: No, no, no, no seals, no sea lions. That was the dolphin that I always thought would be the greatest pet to have in a pool. Would just be so much fun for me, not for him. Him, he, the him who's with us is the Chief Scientist of The Planetary Society, Bruce Betts, who joins us every week here for What's Up. Planetary Radio is produced by The Planetary Society in Pasadena, California, and is made possible by its peace loving members. Mark Hilverda, Jason Davis and Rae Paoletta, our associate producers this week. Josh Doyle composed our theme, which is arranged and performed by Pieter Schlosser. Ad astra.