Universe of Learning 2021-03-11 Exploring Part 2 of 2 page 1

Dr. Quyen Hart 0:03

Thank you for walking us through all the challenges and difficulties in finding Earth, mass planets and Earth sized planets around Sun like stars. And we're gonna hold off questions until after the last speaker. So, let's welcome our last speaker, Dr. Nikole Lewis. Dr. Lewis is an assistant professor of astronomy at and Deputy Director of the Carl Sagan Institute. Dr. Lewis is involved with dozens of observational campaigns with the former Spitzer, current Hubble and future James Webb Space Telescope, that aim to determine the nature of atmospheres. She developed atmospheric models that are necessary for the interpretation of current exoplanet observations and for planning exoplanet observations with future facilities. Before joining the faculty at Cornell, she served as the James Webb Space Telescope Project Scientist at the Space Telescope Science Institute, and was a Carl Sagan Postdoc Fellow at MIT. Dr. Lewis, take it away whenever you're ready.

Dr. Nikole Lewis 1:05

Thank you, thank you, Dr. Dressing and Dr. Ciardi for really setting this up for me. So now you have all the details you need on how we find planets. And then that's where I come in. So, I am not a planet Hunter. I ask the question, "What is in the air of the planets that we find, or do they have air?" As mentioned in my introduction, I primarily do that with NASA facilities. The Spitzer and the Hubble Space Telescopes have really been the workhorse for studying the atmospheres of exoplanets to date. And it's important to remember that neither of those telescopes were actually designed with that type of science in mind. They were designed before we even really knew that exoplanets existed. So, it's been amazing that we've been able to study planets beyond our in detail with these facilities. And now we're looking to the future with the James Webb Space Telescope to do even more. Next slide, please.

Dr. Nikole Lewis 2:01

Alright, so I'm going to focus mostly here on the primary way in which the Spitzer and Hubble Space Telescopes study the atmospheres of transiting exoplanets. There's also a primary way in which the James Webb Space Telescope will study the atmospheres of exoplanets. And that actually leverages one of the methods that was previously talked about, and that's the transit method. And so, when planets are detected via the transit method, you see a dip in their light as they pass in front of their host star, which tells you something about the size of that planet. But it turns out that during that process, the planet, if it has an atmosphere, it's actually filtering the starlight through that atmosphere. And so, what we're able to do is to look at how that planet's atmosphere affects the starlight. Next slide, please.

Dr. Nikole Lewis 2:58

What this looks like in process is that we actually observe the planet at multiple wavelengths of light. And so, if you take a star light and you spread it out over a rainbow. So, you look at the sun and you use a prism, say, to spread that light over a rainbow of colors. If you were just looking at the star, you see basically just a plain old rainbow. But because we have that planet, and it has an atmosphere in front of Universe of Learning 2021-03-11 Exploring Exoplanets Part 2 of 2 page 2

it, what we'll actually see is that the planet appears larger at certain wavelengths of light. So, in this case, the diagram that we have here is a planet that has both sodium and potassium in its atmosphere. And so, at the green and yellow wavelengths of light, the planet actually appears bigger, because it's actually absorbing more light at those wavelengths, because those particular chemical species have basically absorbed light leaving their fingerprints on that spectrum. And so, what we do is instead of just focusing on measuring the rays of the planet over a broad range of wavelengths, so maybe over the entire spectrum of the rainbow, we will get measuring the radius of the planet as a function of wavelength. And that tells us something about the composition of the planetary atmosphere. Next slide, please.

Dr. Nikole Lewis 4:07

And so, using both Hubble and Spitzer to date, we've been able to actually learn a huge amount about what the air is like in planets beyond our solar system. Now we've primarily done this for what we call hot Jupiters. So, these are Jupiter sized planets that orbit very, very closely to their host stars, just like 51 Peg b, the first exoplanet around a Sun-like star was discovered to do. And so usually they're going around their stars every few days. They're pretty hot. We expect that we'll be able to feel gases in their atmospheres. And in fact, using Hubble and Spitzer we've been able to see water. We've been able to measure things like carbon monoxide, titanium oxide, which is in a lot of people's favorite sunscreens. Methane, helium, potassium, sodium and a whole host of other species. We've also been able to see signatures of both clouds, but not like the water clouds that we have here on Earth. No, these clouds are made of common rock species, things like iron and silicates and other materials that we might expect, say, in a lava-type field. We've also seen indications of things like hazes, or just small particles that might be formed through different processes such as photochemistry. Next slide, please.

Dr. Nikole Lewis 5:24

Now, that was what we've seen, mostly for these giant planets. Again, they're fairly easy to detect. Much like how we saw on the other talks, it's pretty easy to detect the Jupiter sized planet, either using a variety of techniques. And so those tend to be the lowest hanging fruit. But we've also used both Hubble and Spitzer to look at some of the first Earth-sized worlds in the quote unquote, "habitable zones" of their stars. So, because planets actually orbit smaller stars, their habitable zones are closer. And perhaps the most famous one you've already heard about is the TRAPPIST-1 system. And Hubble has actually taken a look at the atmospheres of all the planets in the TRAPPIST-1 system. And what we found from those observations is that we know that they don't have a substantial amount of gases like helium and hydrogen in their atmosphere. So, we know that they must, in fact, have what we call secondary atmospheres, atmospheres that formed well after the planet initially formed, just like the terrestrial planets and our own system. We've also looked at worlds like K(epler) 218b, which is sort of a, what we call a sub Neptune, a planet slightly smaller than Neptune, but it is also in the habitable zone of its system. And we've been able to measure water in the atmosphere of this planet, and also measure the presence of clouds. And so, these are really, really important for stuff as we think about trying to find the signatures of other planets out there that look a lot like Earth, especially in terms of their climate. Next slide, please. Universe of Learning 2021-03-11 Exploring Exoplanets Part 2 of 2 page 3

Dr. Nikole Lewis 6:57

Now, most of that work was done, where we're watching the planet pass in front of the host star and watching that starlight get filtered through the planetary atmosphere. But that's not the only way that you can use facilities like Spitzer or Hubble and Webb, to look at exoplanet atmospheres. One thing you can do is to actually directly probe light coming from those planets as a function of time. And the way that this works is that for most of these planets, they tend to orbit in these few day long orbits, which means they're very, very close. And so, we can consider them to be what we call tidally locked, just like the moon is tidally locked to the earth, that means that they're always presenting the same space to their star. And so, what we can do is if we watch a planet through the entirety of its orbit, we can measure its phases, and see how the brightness of, say, the day side of the planet compares to the brightness of the night side of the planet. And what you're seeing on that diagram, in the slide on the left, is that the way that we measure this is when we're looking at a system, we're actually looking at light both from the planet and the star. But we assume that the starlight is fairly constant throughout the planetary orbit. And we look for variations in the overall light of the system to determine how bright the planet is as a function of time. And so, by making these types of measurements - go on to the movie - we're actually able to determine what the atmospheric circulation patterns or weather looks like on those planets. And so, we've actually been able to determine that the weather on exoplanets is pretty crazy, they have winds on order of kilometers per second. It's super hot, super fast winds, much, much, much different than what we see here for the giant planets in the solar system. Next slide, please.

Dr. Nikole Lewis 8:56

And Hubble, in particular, gave us our first look at using this whole spectroscopy method, where we're looking at how the planet emits light as a function of wavelength, in order to determine how the abundance of things like, say, water vapor may vary as a function around the planet. And so, in this observation of the planet WASP 43b in particular, they were able to watch the planet go around its star through the entirety of the orbit, looking at how the temperature of the planet changed with time, but also how that water content changed with time. And so, this was our first way to actually map in more than one dimension and more than two dimensions. What the overall temperature structure of the planet looks like, what its weather looks like, and what the chemical abundance of species like water and its atmosphere look like throughout that atmosphere, critical steps for us to understand in the future, maybe, what the weather and climate of terrestrial planets looks like. Next slide, please.

Dr. Nikole Lewis 9:56

So, we've done magnificent work with both Hubble and Spitzer. Spitzer was retired in January of 2020. And Hubble continues to do great at exoplanet atmospheric characterization work. But we've primarily focused on giant planets again, because they're giving us the strongest signals. And, with the wavelengths of light that we have access to, those are the ones that we've been most able to do. But with the launch of Webb, the James Webb Space Telescope, later this year, we're going to have a whole Universe of Learning 2021-03-11 Exploring Exoplanets Part 2 of 2 page 4

new window opened up to us in terms of characterizing exoplanet atmospheres. And that's going to allow us to look at those smaller and cooler planets. Next slide, please.

Dr. Nikole Lewis 10:40

In particular, the James Webb Space Telescope is really focused on measuring anything in the universe, but in this case, exoplanets at infrared wavelengths. Now, the Spitzer Space Telescope also measured exoplanet light at infrared wavelengths. But it tended to look at those exoplanets into two broad band photometric, what we call photometry channels. So, we only got sort of the broad stroke pictures of what those planetary atmospheres look like. With the James Webb Space Telescope, we're going to get really fine detailed looks at exoplanet atmospheres. So, we can start to really tease out what's in their atmospheres that are leaving fingerprints on their light. That'll be very, very complimentary to observations with the Hubble Space Telescope that looks at exoplanets primarily at what we call visible wavelengths of light that our eyes are sensitive to. Ultraviolet, as well as near infrared wavelengths. Next slide, please.

Dr. Nikole Lewis 11:39

So, with Webb, what we're going to see is that we're going to get more information, or a larger sample of exoplanets, about what's in their atmospheres. In particular, one of the first things that we'll see probably with Webb is that we're going to get really precise observations of how much species like water, methane, carbon dioxide, carbon monoxide, and a whole bunch of other chemicals that we're pretty familiar with from the air around us on Earth, and in the solar system. How much of that is in gas giant planets and other systems. And hopefully, what we can do with that is we can determine something about how those planets formed and evolved that will actually inform how the giant planets in our own solar system formed and evolved. Next slide, please.

Dr. Nikole Lewis 12:30

We'll also do is a lot of atmospheric characterization work on planets that were discovered with the TESS mission that's been mentioned before. And TESS was actually designed really to pick up on exoplanets that are around bright host stars. And so, on the figure on the left, what we're showing is basically the known planets with what we call a day magnitude, or just a brightness greater than 10, or less than 10, in this case, in 2014. But with TESS, we're going to really expand that sample. There's going to be a lot more targets in this size range that we call super Earths and mini Neptunes. So, basically things that don't exist in our own solar system that are in between the size of Earth and Neptune. And so, we actually have no idea what to expect for their atmospheres. And so, this will really be groundbreaking for us to understand, again, how those planets formed and evolved. Next slide, please.

Dr. Nikole Lewis 13:21 Universe of Learning 2021-03-11 Exploring Exoplanets Part 2 of 2 page 5

And just like we did with Spitzer and Hubble, Webb will be used to probe the climates of distant worlds. Again, we focus mostly on these quote-unquote "hot Jupiters" with Spitzer and Hubble, but with Webb, what we're going to be able to do is, again, probe smaller and cooler planets, and we'll start to be able to measure overall weather patterns, such as you're seeing in that middle panel there. What did the jet streams look like on these exoplanets? We'll do some observations of small planets just trying to determine whether or not they have air, which is an outstanding question for many of these smaller terrestrial planets, especially around M dwarfs. We'll also be able to compare different atmospheric models for these planets and determine if complex chemistry is happening in their atmosphere that's due to transport and weather in these atmospheres. Next slide, please.

Dr. Nikole Lewis 14:17

And finally, the Webb Space Telescope will give us our first insights into rocky planet atmospheres beyond the solar system. Although we did look at the TRAPPIST-1 planets with Hubble, we really couldn't get down to the, what we call, precision level needed to determine the compositions of their atmospheres. But with Webb, we're probably going to be able to get there. We'll be able to measure things like carbon dioxide and water and other important chemical species and determine if they are in fact present in the atmosphere that the TRAPPIST-1 planets. So, this will be an important proving ground for future missions that may consider the abundant diversity of exoplanet atmospheres out there. That's my last slide, right? Yes. And so, this really is just setting the stage. Webb is going to give us a huge amount of information on planets, both big and small. And it's really going to move us along in understanding the big diversity of atmospheric compositions out there. As we continue to ask that question, "Are we alone in the universe?" Thank you.

Dr. Quyen Hart 15:23

Thanks, Dr. Lewis, for sharing your work on characterizing exoplanet atmospheres with Spitzer and Hubble and the future prospects with the James Webb Space Telescope. So, thanks to all our speakers for your insights into the current exoplanet studies, it's been really fun listening to your talks. So, we're gonna pivot now to our Q&A segment of the science briefing. So, in the interest of time, let's limit it to one question per person. When you want to ask a question using the microphone, unmute yourself, say your name and ask your question. For WebEx you can click on the microphone icon. Red means you're muted and gray means you're not. For those of you are on the phone, press star six to mute and unmute. And remember to mute yourself when you're done. Also, feel free to type your questions in the chat window. And I can try to pose that question here. So, I'll start with one question from someone who dropped it in the chat here.

Dr. Quyen Hart 16:19

Question for Dr. Dressing: Is it possible to easily get confused with planet transits and sunspots? How do you figure out that is the transit and not a sunspot?

Universe of Learning 2021-03-11 Exploring Exoplanets Part 2 of 2 page 6

Dr. Courtney Dressing 16:30 in the diagram you saw, the sunspots looked about the same size as the planet. So that's a natural question. The main thing that helps us out is that stars tend to rotate on a much longer timescale than planetary orbits. So, our sun takes about a month to rotate on its axis, which means if we saw a decrease in brightness caused by a spot, it would last for a full month. The planet, in contrast, crosses the whole disk of the star on a timescale of hours. Another way you can make sure you're seeing a planet and not just a star spot is to use multiple methods. If you get radial velocities and transit data and they point to the same answer, that's a good sign you have a real planet. You can also look at different wavelengths of light as well, to see the same transit depth in different colors.

Dr. Quyen Hart 17:12

We have another question in the chat. What is the software you use to analyze these objects? I think this might be for Dr. Dressing and Dr. Ciardi, as well as Dr. Lewis.

Dr. Courtney Dressing 17:30

We use a lot of Python, we also use an older language called IDL, which folks outside of astronomy probably have never heard of, and never will. I sometimes use Fortran. So, it's really a mix. And we all sort of have our own preferences.

Dr. David Ciardi 17:45

I think one of the big parts of this is that there is no off the shelf package that we use. We often write our own software to do very specific tasks. The community has gotten very good about sharing nowadays in a way that we didn't earlier on. And so often times, this will run a software package that other people will then use. And it helps, in many ways helps to verify the results by being able to run that other scientist's code and then running your own code to see if you get the same answers.

Dr. Quyen Hart 18:29

Great, thank you. For those of you who are on the call, feel free to unmute yourself and ask our speakers some questions.

Dr. Quyen Hart 18:50

I'm not hearing some, so I'm going to ask some more questions that are coming down in the chat window here. For Dr. Lewis, are you going back to work on just JWST? And a follow up question related to the same topic: Once Webb is launched, how long before images are transmitted?

Universe of Learning 2021-03-11 Exploring Exoplanets Part 2 of 2 page 7

Dr. Nikole Lewis 19:09

So, I will of course be excited when Webb gets up there. But I will continue with Hubble and actually ground based observations as well. In particular, Webb will give us a really excellent view into the infrared world and infrared spectra of exoplanets. But to understand all the processes that are happening in an exoplanet atmosphere, you really have to also see what's going on at other wavelengths of light. And in particular, the ultraviolet wavelengths are very important, which currently only Hubble Space Telescope has access to. So, I will continue to use a variety of instruments out there and hopefully they start to tell us sort of a coherent story. In terms of the first images coming down from Webb. So, you know, I can't speak formally on that. I know that's a tightly guarded NASA Headquarters secret, but there will be about six months of what we call commissioning at the beginning of the lifecycle of Webb, during which some of those first images will be taken and then eventually released to the public.

Dr. Quyen Hart 20:14

Thank you, Dr. Lewis for that. Some more questions being dropped in the chat: With radial velocity measurements, how do you differentiate between the effects of multiple planets on a shared star?

Dr. David Ciardi 20:30

Courtney, are you gonna answer that?

Dr. Courtney Dressing 20:32

I was gonna let you go first.

Dr. David Ciardi 20:34

Okay. That's a really excellent question. And the short answer is, you just need lots and lots of data. If you only have a few measurements, it's very difficult to tell if there's one or two or four planets, and you can often get yourself very much confused. And there are plenty of examples of scientific publications where early on, there was a measurement of a single planet, and then further work by other scientists revealed, oh, indeed, there are actually more planets in this system, and the estimates of the masses of the original planet were actually wrong. And so, it really comes down to lots and lots and lots of data.

Dr. Quyen Hart 21:21

And one final question here: In the context of the growing catalogue of exoplanets, would you regard our solar system as an outlier rather than a typical ?

Universe of Learning 2021-03-11 Exploring Exoplanets Part 2 of 2 page 8

Dr. Courtney Dressing 21:32

That's the question we all wish we could answer. The hardest thing is that with our solar system, we can't detect most of the planets. We could detect Jupiter, we could detect Earth if we got really, really lucky. And we were looking at that star and it was right nearby. What we can say is that there are many planetary systems that are totally different from our own. I saw in the chat a comment about these super Earths that don't appear in our system. Those are planets with radii between those of Earth and Neptune. We don't have those. Why is that? We don't know for sure that there aren't other stars out there with solar systems that look very similar to ours. And by that, I would mean, multiple planets, very flat, all the planets in the same plane, like a record or CD, and having rocky planets in the center, closer to the sun, and more gaseous planets further out. That's something that we hope to be able to answer with the upcoming portfolio of missions like the Roman Space Telescope, and LEVOIR, and HabEx and everything else that comes along down the road. But the jury's still out on that one.

Dr. David Ciardi 22:29

And it's actually one of the things that Dr. Lewis talked about, that it's really important that we're getting to not just the five mass independents, but it's their content. And all of the atmospheric characterization to which you refer and I think is really crucial for us understanding the solar system in context of all the other solar systems.

Dr. Quyen Hart 22:51

Great, thank you so much. So, I wanted to thank our speakers, again, for your great presentations. We are officially at the end of the hour for our presentation. I do have additional resources. So, if you have time, for those of you who are joining us, if you want to stay on for another 5-10 minutes, I'll go through those resources. But we wanted to give everyone the opportunity to leave if they needed to go on to another meeting. Speakers, the same goes for you. Oh, but if you'd like to stay on, please do. And if you want to answer some of the questions that we didn't get to in the chat, you can type out some answers in there if you'd like. There were a couple that we didn't get to. So, let me go through our resources here. So, I've compiled some things here to help you understand exoplanets in general, and also think of resources that you can use with your audience in mind. So, for example, you might want to learn more about exoplanets in general, and what kinds of different types of exoplanets that are, like gas giants, Neptune-like super Earths or terrestrial planets. So, we have websites, linked in this PowerPoint, but we also have them all broken out in a Word document which you can download from the Universe of Learning website. Next slide, please.

Dr. Quyen Hart 24:03

If you want to take a really deep dive in all the different exoplanet detection techniques that you heard about today, you can go here and the resources have some really nice animations to provide your audience with captivating visuals. Next slide. Universe of Learning 2021-03-11 Exploring Exoplanets Part 2 of 2 page 9

Dr. Quyen Hart 24:24

Our NASA's Universe of Learning resources include these great ViewSpace interactive tools on some of these detection methods. So, you can see the lower right-hand side is an image that you saw on Dr. Ciardi's presentation, which is about detection. And so, you can take these interactive tools, and you can slide a bar left and right and see changes, so you can actually see those exoplanets orbiting around that particular star and that direct imaging. You can explore exoplanet atmospheres like Dr. Lewis was just talking about, as well as transiting techniques that were talked about from all speakers. Next slide, please.

Dr. Quyen Hart 25:00

Within ViewSpace. Now you might be familiar with ViewSpace and seen them in libraries, or museums. But anybody can access these videos at the ViewSpace library here, and you can see short video segments on current events, exoplanet discoveries and more. Next slide.

Dr. Quyen Hart 25:21

You can learn more about TESS and Kepler and how many exoplanets have been detected so far here. So, in this slide here, you see it I took this the other day. So, you can see, there are 120 confirmed TESS planets there and Kepler, I'm trying to see the number here. So, you can take a look and see what those numbers look like and how many have been found. Next slide, please.

Dr. Quyen Hart 25:44

If you really want to take a deep dive to learn more about a particular exoplanet, you can search through the exoplanet catalog, which is a continuously updated exoplanet encyclopedia. It combines interactive visualizations with detailed data on all the known exoplanets. I really like this resource too, because it gives you a nice snapshot of how many exoplanets have been confirmed, how many of each kind have been discovered, as well as the percentage discovered based on all the different detection methods. So, it really gives you a snapshot if you get those questions from your audiences. Here is a great place to find that information. Next slide, please.

Dr. Quyen Hart 26:20

Now, you can also use a program called Eyes on Exoplanets. It's a scientifically accurate 3D universe that allows you to explore those thousands of exotic planetary systems known to orbit distant stars. So, you can do this on the web and you can pick a star, change the orientation, look to see where the habitable zone is around a star. Now, if you're putting together images and visuals to support your presentations, you can go to AstroPix to look for images related to exoplanets. Those include artistic renderings, added a few direct images that we have. Next slide please. Universe of Learning 2021-03-11 Exploring Exoplanets Part 2 of 2 page 10

Dr. Quyen Hart 26:58

They also introduce your audience to the Exoplanet Travel Bureau with beautiful brochures about visiting exoplanets. These travel brochures and the renderings examine what the exoplanet surfaces might look like if you were to be able to visit. Some of these posters have coloring sheets. They're available to engage your younger audiences. Some of these are also available in Spanish. The speakers talked about the TRAPPIST-1 system, and how it looks very different than the solar system. So, we have a hands-on activity where you can create a scale model of the TRAPPIST-1 system, and you can reference it to the solar system as well. Next slide, please.

Dr. Quyen Hart 27:36

Now, many of us have pivoted to virtual events. And so, you can think creatively out of the box. And this is one example here that I've done, where you can ask your audience to imagine going to an exoplanet that you're talking about and make their own travel poster here. Encourage them go outside when the weather is warmer, do the chalk, do the whole TRAPPIST-1 system on the ground and put it next to the solar system. They get a really nice scale there. Next slide, please.

Dr. Quyen Hart 28:06

Or only for a more advanced audience, Exoplanet Watch is a citizen science project supported by NASA's Universe of Learning to observe transiting exoplanets, which again, planets that are outside of our solar system, with small telescopes. So, if you want to get involved in really contributing to this area with authentic research, take a look at Exoplanet Watch. Next slide.

Dr. Quyen Hart 28:28

Now, we also have lots of resources at Universe Unplugged where you can explore habitable zone theories about planets in the habitable zone and traveling around and the story here. Or you can also look at commentary from scientists and Ask an Astronomer Live series. So, if you go to this Universe Unplugged website, you can see that they have these live series once a month. And there was just a recent one on exoplanets. So, this one here is careers in planet hunting. So, these are recorded, you can go back and take a look. Next slide please.

Dr. Quyen Hart 29:03

Definitely hear about the breaking news, you can go here at the exoplanets.nasa.gov/news to find the most recent information about exoplanet research. Next slide.

Universe of Learning 2021-03-11 Exploring Exoplanets Part 2 of 2 page 11

Dr. Quyen Hart 29:15

That was a lot of different resources for you to go out and learn some more and share with your audience. Now if you wanted a one stop resource here with a variety of materials in it, you can take a look at our comprehensive "Other Solar Systems, Other Earths" resource guide. As you can see here that we have backgrounds, posters, activities. So, take a look. It's linked here and we hope that you find that these resources are helpful as you plan your activities and your talks and your professional development with your staff. So again, let's thank our three speakers. Dr. Courtney Dressing, Dr. David Ciardi, and Dr. Nikole Lewis for spending the time with us today. Would any of our speakers like to make any last closing comments?

Dr. Nikole Lewis 29:59

I just wanted to thank you all for coming in. I had a great time answering your questions.

Dr. David Ciardi 30:04

Thank you very much for the invitation, and that I hope you guys enjoyed all of it.

Dr. Quyen Hart 30:08

And thank you, everyone. Thanks to all of you listening out there, too. Remember that all our talks are recorded and posted on our member websites. And you're encouraged to share this presentation as professional development with your colleagues, including your education staff and your museum docents. If you have further questions about this topic, either now or in the future, you can reach out to us via the MIE Alliance Team Chat or by email is fine, too. Our next Universe of Learning. telecon will be on May 6 2021. And the topic will concentrate on Studying the Universe in the Infrared. We hope to see you online in the future. And, as always, the most up to date information for our science briefings and resources are on our website. Have a wonderful rest of your day. Bye, everyone.

Dr. David Ciardi 30:56

Thank you. Bye bye.

Amelia Chapman 30:58

Thank you.

Transcribed by otter.ai and Rachel Zimmerman-Brachman