Episode 30: Pretty Planetary Nebulae
with Kelebogile Bonokwane
This week we’re joined by Kelebogile Bonokwane who is a National Astrophysics and Space Science Programme (NASSP) Master’s student at the South African Astronomical Observatory (SAAO).
Kelebogile talks with us about her MSc project on planetary nebulae. She is investigating whether binary stars sit at the heart of these magnificent structures and are responsible for their unusual shapes.
Her work utilises the Southern African Large Telescope (SALT) as well as NASA’s Transiting Exoplanet Survey Satellite (TESS). TESS is an all-sky survey mission designed to discover thousands of exoplanets around nearby bright stars. Kelebogile is using this data to study the central stars of planetary nebulae.
Kelebogile was recently awarded the SAAO-SALT prize scholarship. She plans to do her PhD on X-ray binaries, investigating the relationship between X-ray and radio emission in order to study the accretion process and relativistic jet production.
This week’s guest
Planetary Nebulae He 2-47, NGC 5315, IC 4593, NGC 5307
Image Credit: NASA, ESA, and The Hubble Heritage Team (STScI/AURA)
NASSP is a multi-institutional postgraduate initiative funded by the Department of Science and Innovation (DSI) through the NRF. The aim of NASSP is to train graduates in astronomy, astrophysics and space science in order to contribute to national programmes. Learn more about NASSP here.
Social media by Sumari Hattingh.
Jacinta: [00:00:00] Welcome to The Cosmic Savannah with Dr. Jacinta Delhaize
Dan: [00:00:08] and Dr. Daniel Cunnama. Each episode, we’ll be giving you a behind the scenes look at world-class astronomy and astrophysics happening under African skies.
Jacinta: [00:00:16] Let us introduce you to the people involved, the technology we use, the exciting work we do, and the fascinating discoveries we make.
Dan: [00:00:23] Sit back and relax as we take you on a safari through the skies
Jacinta: [00:00:36] Hello and welcome to episode 30!
Dan: [00:00:40] Yay! Happy…Birthday? Yeah, 30th episode. Can’t really call it a birthday.
Jacinta: [00:00:49] Season 3 Episode 30.
Oh, that’s nice.
Dan: [00:00:52] Sure.
Jacinta: [00:00:53] Okay. 30. Well, we’re both in our thirties.
Dan: [00:00:55] Yes. Hubble’s 30 years old. We’re talking about Hubble! Well just a little bit. We’re talking about planetary nebula. Hubble takes nice photos.
Jacinta: [00:01:04] So I guess it was launched back in 1990 then. Yeah. Do you remember that year, Dan?
Dan: [00:01:09] Do you remember that year? Now I’m feeling old. It’s my birthday next week, happy birthday to me! Well, actually it will have been my birthday and I’ll be 36.
Jacinta: [00:01:23] I don’t remember 1990.
Dan: [00:01:25] I shouldn’t be telling people my age. Right, back to the episode.
Jacinta: [00:01:31] Before we get into the episode, what have you been up to this week, Dan?
Dan: [00:01:34] I put in a proposal for another planetarium film!
Jacinta: [00:01:37] Did you?
Dan: [00:01:39] I did. I put a funding proposal in for another planetarium film. And this time inspired by episode 28, a couple of weeks ago. The proposal for this one is African star lore. Finished. 24 minute film on African star lore. Multicultural, multilingual.
It’s going to be huge.
Jacinta: [00:01:58] I can’t wait!
Dan: [00:02:00] Yeah. Let’s hope they give me the money. Money is hard to come by. Right? What have you been up to?
Jacinta: [00:02:05] I’ve been attending the 2020 SARAO Bursary Conference. And SARAO is the South African Radio Astronomical Observatory. This happens every year and you’ve probably heard several of our episodes in the past where we’ve interviewed other people who are attending those.
So this year, of course, it’s virtual, it’s online. Just as the SAAO recent conference was online and it’s actually working pretty well. This year we have all pre-recorded quick 90 second talks, which get played in succession. And then there’s a question and answer session where people can ask us questions live and we are online to answer them.
And then we meet in this thing called Gather Town, which I hadn’t heard of before. But you’re kind of like in a video game and you’ve got your little avatar of yourself and you walk around the spaces of this online conference venue and you meet other people there and you can talk to each other. Because it turns your videos on and your sound on you talk to each other and it’s working surprisingly well, I really feel like I’m walking around and seeing these people who are on opposite sides of the world at the moment.
Dan: [00:03:10] That is weird.
Jacinta: [00:03:11] Yeah. So really well done to the organizers.
Dan: [00:03:13] Well I’m glad it’s working out.
Jacinta: [00:03:14] Yeah, it’s cool.
Obviously it doesn’t beat real life, but this is what we have to do at the moment.
So it’s working nicely.
Dan: [00:03:22] 90 second talks though!
Jacinta: [00:03:24] Yeah. That’s very quick, but at least everyone’s getting a shot to talk. So this is mainly for the post-graduate students and the post-docs who are being supported by SARAO and we meet every year and we’re hearing all about the amazing discoveries and detections that MeerKAT has been making this year.
So I think this was maybe the first time ever that we’ve had a particular session, which was this morning, dedicated just to new MeerKAT results. So, yeah, it’s the first year that they’re all just churning out and so many people have made so many different discoveries and it’s really exciting.
Dan: [00:04:00] And every is going to need an extra session.
Jacinta: [00:04:02] Hopefully. Yeah. That’s what we’re after.
Okay, so let’s get back onto this episode’s topic.
Dan: [00:04:09] So today we will be discussing?
Jacinta: [00:04:11] Today we’re going to be discussing planetary nebula, which are the endpoint of stars that are not particularly massive. So stars that are similar to the sun or maybe around two solar masses, meaning two times the mass of the sun. These stars, they don’t die in these big dramatic supernova explosions, which we often talk about. Rather, they kind of fade away.
So they start burning different elements other than hydrogen. And then they release their outer layers, which just kind of float off into space. And they are kind of lit up by the central remaining star or white dwarf, I suppose. And they create some beautiful colors that we’ve seen in pictures, particularly from Hubble.
Dan: [00:04:56] Yeah. So there’s these sort of cloudy shapes around the central star, which are in numerous different colors once they’ve been tinted. I think the shapes are incredible. They’re definitely some of the most eye catching images that come out of Hubble.
Jacinta: [00:05:13] So who are we speaking with today about these planetary nebulae?
Dan: [00:05:15] So today we are joined by an MSc student. She’s just finishing her MSc project at the University of Cape Town. And her name is Kelebogile Bonokwane. And she is from Kimberly in the Northern Cape originally, where our telescopes are. Not in Kimberley itself, but in the Northern Cape. And she’ll be talking to us about her project and some of the telescopes she’s been working on.
Jacinta: [00:05:37] Just a couple of things to mention.
First, sometimes she calls planetary nebula, PN for short. We also have a little discussion about spectrometry and photometry. So Dan, what’s the difference between those two?
Dan: [00:05:50] Photometry is basically collecting little photons of light and measuring how bright they are. And spectrometry is collecting little photons of light and measuring their frequency or wavelength.
So you can split them up into their constituent frequencies and look at the colours and frequencies, and you can tell completely different things other than just the brightness.
Jacinta: [00:06:14] You can hear some wind in the background there.
Dan: [00:06:16] It’s Cape Town. It’s summer.
Jacinta: [00:06:18] It’s very windy in Cape Town in summer.
Right. So that’s the difference between spectrometry and photometry and I think that’s all we need to know.
So let’s hear from Kelebogile.
Dan: [00:06:36] Today we’re joined by Kelebogile Bonokwane. Hello Kelebogile. Welcome!
Kelebogile: [00:06:41] Hi, thanks for having me.
Jacinta: [00:06:42] Welcome to The Cosmic Savannah. It’s a pleasure to have you.
Kelebogile: [00:06:45] I’m glad to be here.
Jacinta: [00:06:46] Can you tell us first just a little bit about yourself? Who you are, where you’re from and what your role is?
Kelebogile: [00:06:52] I am Kelebogile Virginia Stephanie Bonokwane. My mother gave me many long names.
So I am from Kimberly in the Northern Cape. I grew up in sort of a Kgosi township of Galeshewe. And right now I’m a bit of a student in transit between Masters and PhD in astrophysics. Specifically stellar astrophysics.
Dan: [00:07:20] Where are you based?
Kelebogile: [00:07:21] I am at the UCT and SAAO.
Dan: [00:07:24] So split between the South African Astronomical Observatory here with me, and at the University of Cape Town.
Jacinta: [00:07:30] With me!
Kelebogile: [00:07:32] Yes.
Dan: [00:07:33] Maybe you could just tell us a little bit about how did you get into astronomy? Where did you study your undergrad?
Jacinta: [00:07:38] What got you interested in the first place?
Kelebogile: [00:07:40] So I remember very particularly, I think I was in grade four and we were learning about the telescope and Galileo Galilei and I was like wow this is interesting!
And I sort of had this astronomy thing in my head ever since. Although I went to a technical school. So we did electrical, civil and mechanical technologies. I was like okay, maybe I might become an engineer. But I decided to just pursue astronomy instead. That’s what I found interesting. I was like, I’m going to be a scientist.
And so that’s when I came to Cape Town from Kimberley. I’ve been at UCT since undergrad. And I did physics as well as astrophysics majors in undergrad. And I decided to just stick to and pursue astronomy. It’s what I found interesting. It’s what I liked. And I wanted to be at a point later in my career where I was doing research and I was doing something that I really liked and enjoyed.
And so I am here now sort of in my post-grad continuing with astronomy.
Jacinta: [00:08:49] That’s
awesome. So what do you study? What’s your research been about so far?
Kelebogile: [00:08:53] So it’s been planetary nebulae since honours. Since my honours project. And I sort of continued with that into my Master’s project.
Dan: [00:09:04] Can you just explain for the listeners, what is a planetary nebula?
Because it’s not what you think it is, right?
Kelebogile: [00:09:10] Similar to people, stars evolve over a lifetime. They’re born and they die. And so the planetary nebulae, they are where a star evolves towards the end of its life time. And what happens is inside stars you have this constant, continuous nuclear reactions happening.
And you have these elements formed. Hydrogen, helium, the first few elements on the periodic table. So what then happens when a star becomes a planetary nebula, is that there’s been so much gravity on the star itself, that the temperature rises enough to sort of drive off the surface material off the star.
It does this through very strong winds. And so you have this expanded material of guests driven off the surface of the star and then this hard core at the center, sort of heats up this material. And that’s what you see as this glowing nebula. So that whole system is what you have as a planetary nebula. The core at the centre and this glowing nebula around it.
Dan: [00:10:20] And they have nothing to do with planets.
Kelebogile: [00:10:24] No.
Jacinta: [00:10:25] Do you know why it was named that way?
Kelebogile: [00:10:27] I’m not sure.
Dan: [00:10:28] I do. Actually I do. I mean, it was the earliest astronomers, maybe 200 years ago. I think it might’ve been William Herschel even. They were looking at these objects or seeing them through small telescopes and they looked more planet like than star like.
Because they had this extra sort of shape and colour. They’re beautiful objects, planetary nebula. We’ll post some pictures on the website. But Hubble has taken some incredible photos of planetary nebula. So I think that was why they were called planetary nebula at first.
Jacinta: [00:11:05] So it was thought that they were from planets?
Dan: [00:11:07] It was thought that they were planets. Cloudy planets or something going around a round planet. But now we know that, as you said, they’re the end point of a star’s life and have nothing to do with planets. In fact, if there was a planet there, then that probably wouldn’t end very well for
Jacinta: [00:11:23] So what do they actually look like, Kelebogile? Maybe you can tell us a bit more about the weird and wonderful shapes that they form.
Kelebogile: [00:11:31] Most planetary nebula are just spherical in structure or shape. But others have these bipolar lobes and jets, or these disks around the system. That’s what the ones look like that I’ve been studying. The sort of more interesting looking ones. The ones that have these interesting shapes that morphologies.
Jacinta: [00:11:57] And do you know why they have such strange shapes and morphologies?
Kelebogile: [00:12:01] Well, that’s sort of what we are trying to figure out. In the literature, it’s been speculated that it’s due to the stellar rotation and also others say that the magnetic field of the object can influence it. But those two scenarios don’t really support it, or wouldn’t be able to sustain that kind of shaping.
And so what’s been seen more recently is that there have been binary stars sort of discovered in these kinds of planetary nebulae. And so that’s what the basis of my research was. Trying to find binary central stars in these interesting PN (Planetary nebulae) .
Dan: [00:12:45] Two stars within the planetary nebula itself? Or is the planetary nebula around the one star and the other star is further off?
Kelebogile: [00:12:53] Well, what you can have is the common envelope of the two stars. So most stars would reside inside of the common envelope and then the envelope can expand into the nebula and then sort of influence the shape like that. So that’s kind of what most simulations have modelled – how binaries can influence the shape of the planetary nebula.
Jacinta: [00:13:18] Okay. So there’s two stars in the very center and then the planetary nebula is very big and around both of them.
Kelebogile: [00:13:24] Yes.
Jacinta: [00:13:25] Okay.
Dan: [00:13:25] Oh right!
Jacinta: [00:13:26] Have you been looking into this problem with any particular planetary nebula?
Kelebogile: [00:13:31] Yes for my Master’s research, I looked at three objects. Hen3-1333, Hen2-113 and Hen2-47. And Hen2-47 is the classically-known Starfish nebula. It looks like a starfish.
I looked at those because they were very interesting looking. They were all sort of multipolar in shape. So you had that interesting morphology, but also they had these extra features that added to how interesting they were and how they screamed that they must be binary central stars.
And that’s why I chose those objects. Those are the three that I looked at recently.
Dan: [00:14:15] And how are you observing them? Which telescopes are you using?
Kelebogile: [00:14:18] I used the South African Large Telescope SALT. And I also used the TESS telescope – the [Transiting] Exoplanet Survey Satellite, which is a space-based telescope. And the reason why I did that is because I wanted to do a very quantitative study.
So I got to spectroscopic data and also photometric data, to cover all bases.
Jacinta: [00:14:42] What kind of light does TESS collect? Is it optical light?
Kelebogile: [00:14:45] Yes.
Dan: [00:14:46] And it’s just collecting photometric data. So just brightnesses of stars, right? But it does that very regularly.
Kelebogile: [00:14:52] Yes, very.
Dan: [00:14:53] How regularly does it do it?
Kelebogile: [00:14:55] The data I had, it was taken at a 30 minute cadence.
And it does this continuously for about 27 and a half days.
Dan: [00:15:04] That’s amazing.
Jacinta: [00:15:05] So this satellite telescope is looking at the exoplanet every 30 minutes. Is that right?
Dan: [00:15:11] It’s looking at a field of the sky actually. So it’s looking at quite a large field of sky and it looks at it for 27 days consecutively taking an image every 30 minutes. So you’re looking at thousands of stars.
You didn’t use TESS specifically, you didn’t ask TESS to point for you. You’re just using TESS data, which they’ve released to you?
Jacinta: [00:15:31] From the archive?
Kelebogile: [00:15:32] Yes.
Jacinta: [00:15:33] And what did you find? What did you see?
Kelebogile: [00:15:35] Unfortunately, we had a non-detection in terms of finding the binary, but what we were able to do from our results is constrain the orbital period parameter.
And this is assuming that the features that we see, the shapes that we see, is because of a binary system.
Jacinta: [00:15:55] You were looking for a binary. You were trying to figure out whether these weird shapes were caused by binary stars at the center. You mentioned an orbital parameter. So you’re trying to find the amount of time it takes for the star to rotate around the other star?
Kelebogile: [00:16:09] Yes. And if you prove that does exist…
Jacinta: [00:16:13] then you’ve found a binary, right?
Kelebogile: [00:16:14] Yes.
Dan: [00:16:15] With the TESS data, you’re looking at the brightness of a star, or in this case the star at the center of a planetary nebula. And you’re looking for a change in its brightness, which will indicate that there’s another star there. Do these two stars have to be eclipsing?
I mean, does it have to be an eclipsing binary where the one passes behind the other in order for you to detect a dip in light?
Kelebogile: [00:16:37] It doesn’t necessarily have to be eclipsing, but you can tell from the sort of variation in the light curve that you make from this photometric data, if there is a signal detectable from that.
Jacinta: [00:16:54] Okay. So there could be some pattern in the light curve, even if it’s not eclipsing. Do you also look at the velocities of the stars? Like whether they’re actually wobbling?
Kelebogile: [00:17:03] Yes, so that was done with the spectroscopic data from SALT. I made radial velocity curves, and I had the light curves also to work from.
Jacinta: [00:17:15] Okay. So you’re looking at the variation in the light and whether the star is moving to figure out whether that’s a binary or not. Yes.
Dan: [00:17:22] So with SALT you’ve got a very high resolution spectrograph, a very high resolution spectrum. And from those lines, by looking at it at different times, presumably also fairly regularly, you can see whether the star is moving towards or away from us. Correct?
Kelebogile: [00:17:38] Yes.
Dan: [00:17:39] And how regularly we were you doing that with SALT? How much data did you take from SALT?
Kelebogile: [00:17:44] It wasn’t an even sample, but the spectra that we had was taken over about 300 days. And so for the different objects, there was about 60, 58 and 35 amounts of observations. They were taken about 10 days between each observation. A little incoherent. So it was a bit of an uneven sample.
Dan: [00:18:11] So it was hard to find a sort of an easy period or pattern?
Kelebogile: [00:18:15] Yes.
Jacinta: [00:18:16] Were there any, maybe, slight hints of a binary?
Kelebogile: [00:18:20] There was for the Starfish nebula. There was this period that sort of stood out. It was 14 and a half days. What we do when we find a signal is that we try to phase up the light curve using that signal.
Jacinta: [00:18:36] Okay. So of the three planetary nebula you looked at to find binaries you’ve got “No. No. Maybe.” Is that right?
Kelebogile: [00:18:45] yes.
Dan: [00:18:46] Is the plan to carry on? Have you got plans to collect more data and try and clarify some of these things?
Kelebogile: [00:18:54] Well, because our results were saying no short periods, which is less than 10 days, we are assuming that they have very long orbital periods. And so we just need a little more data, or a lot more data! Because we have about three years of observations and we are assuming that the orbital period should be at least around thousands of days. So we need a lot more observations and monitoring with SALT to pin down if there is something.
Jacinta: [00:19:30] Okay. So your results don’t necessarily mean that there isn’t a binary. The obit of the stars around each other could be on a much longer time scale than you’ve already had a chance to look at.
Kelebogile: [00:19:40] Yes.
Dan: [00:19:40] And that wouldn’t be that long. If it’s a thousand days, that’s two and a half years or something.
That’s a slightly bigger orbit than the Earth, but not massive when you’re looking at two different stars. How big are these planetary nebula on the scale of the Solar System?
Kelebogile: [00:19:57] Very big. I guess if the Sun were to go into its planetary nebula phase, it might absorb Jupiter, I think.
Jacinta: [00:20:06] Oh, cool.
Kelebogile: [00:20:07] Yeah.
Dan: [00:20:09] That’s pretty big!
Jacinta: [00:20:10] Yeah!
Kelebogile: [00:20:12] And then there won’t be Earth by then.
Jacinta: [00:20:14] No. What would happen to the Earth?
Dan: [00:20:18] Vaporized.
Kelebogile: [00:20:19] Yeah.
Dan: [00:20:21] Vaporized.
Jacinta: [00:20:22] Yeah. I guess it would be already eaten up when the star becomes a red giant, right?
Kelebogile: [00:20:27] Yes.
Dan: [00:20:28] Is the sun expected to go into a planetary nebula phase? What are the requirements for a star to go into this phase?
Kelebogile: [00:20:36] Planetary nebulae progenitors, which are the first stages of the star are similar to the Sun. So they have similar masses, which is around two solar masses. So you would expect the Sun to follow the same evolution as a regular planetary nebula. So you would expect it to go into a planetary nebula phase.
Dan: [00:20:59] Yeah. So first it expands into this big red giant, and then that will kind of dissipate into a planetary nebula phase. Oh, that’s not a bad way to go.
Jacinta: [00:21:08] And do you know why they make all of these beautiful colors?
Kelebogile: [00:21:11] So it’s the elements often and then sometimes also the part of the spectrum it’s observed in. But for PN, from what I can tell, it’s mostly the elements.
So you have oxygen, nitrogen and sulfur making the blue, green, and red that you see. And those colors are sort of composites made. And then that’s how you see these different colors or what you would have perceived the PN to look like.
Jacinta: [00:21:44] So, do you think you would see those colors if you looked at it with your eyes or are they sort of false color images meant to represent the emission of different chemicals or elements inside the planetary nebula?
Kelebogile: [00:21:56] It would be because of that. False colors.
Jacinta: [00:21:58] Yeah. We spoke to Jayanne English a few episodes ago and she was actually one of the people at NASA who was making the image composites.
Dan: [00:22:06] And from Hubble too. So she presumably did play with some of the planetary nebula.
Jacinta: [00:22:11] Yeah, maybe even some of these planetary nebula. What are your plans for the future?
Kelebogile: [00:22:15] Well for now, I think I can only tell you about three or four years into the future.
Dan: [00:22:21] Oh, that’s more than I could say.
Kelebogile: [00:22:24] I’m starting my PhD next year, early next year. And that’s sort of going into a bit of a new field in X-ray binaries, working with X-ray and radio data. Which is something very, very new for me. But it’s an exciting challenge, I guess. But it’s still sort of sticking with stellar and binaries. Sort of a theme that I have going on.
Dan: [00:22:49] Where will you be doing that?
Kelebogile: [00:22:50] I will be at the SAAO. Okay, cool.
Jacinta: [00:22:53] Okay. Congratulations!
Okay, great. So I think when we’re nearly at the end now. Do you have any final messages for listeners?
Kelebogile: [00:23:00] Well, if they’re already listening and watching this, they’re already doing something good. But a message for them, I’d say, continue to listen and watch, learn about the science and whatever interests you in the field.
And also just continue to expose yourself to the different people that come here and tell you the paths they’ve taken to get to where they are. It can be something inspiring for you as an individual, regardless of whatever you are doing. And just continue to take care of yourself, stay safe with these times that we are in and be kind.
Jacinta: [00:23:42] That’s fantastic. Is that the advice you’d give yourself if you could go back in time and see little you when you were in grade four and interested in astronomy.
Kelebogile: [00:23:51] Yes.
Jacinta: [00:23:52] Great.
Dan: [00:23:53] Thank you. And thank you for your inspiration.
Kelebogile: [00:23:55] Thank you so much.
Dan: [00:23:56] It’s greatly appreciated.
Jacinta: [00:23:58] Yeah. Thank you very much for joining us and we hope to speak to you again soon.
Kelebogile: [00:24:01] It was nice being here.
Jacinta: [00:24:11] Okay. So interesting to know that these pictures of the planetary nebula, which have fascinated me since I was also very young, are false color images.
Dan: [00:24:19] Yeah. So we’ve discussed this previously, as you mentioned, episode 17 if you want to go back and listen, and we chat to somebody who does exactly that. So it’s more than just making up some false colors to make it look pretty. It’s not just sticking it into Photoshop and making it look nice. They actually try and hold onto the science. So adjust the image according to its frequencies and then use the different colors to represent those frequencies. So you actually, to use quite a big word, ‘elucidate’.
You shed light on what exactly is going on.
Jacinta: [00:24:52] Yeah.
Dan: [00:24:53] Yeah, a great chat to Kelebogile too. It’s really cool to hear stories of people who grew up in South Africa, getting interested in astronomy at a young age, and then having the opportunity to study it and become an astronomer. It’s really special and wonderful to see.
Jacinta: [00:25:10] Yeah, definitely.
Cool. All right. Well, it was really awesome to talk to Kelebogile.
Dan: [00:25:15] Yeah, and we’ll let you get back to your Bursary Conference. Some exciting science I’m sure coming out and hopefully we can earmark some people to interview, including yourself. And l keep trying to get you to talk about your new paper.
Jacinta: [00:25:28] It’s not accepted yet, but as soon as it is…
Dan: [00:25:30] okay. Soon, soon, soon.
Jacinta: [00:25:32] Yeah. I’ll be the guest on one of the episodes.
Dan: [00:25:36] And do let us know if there’s anything else exciting coming out of the conference.
Jacinta: [00:25:40] Oh, there is. I’ve already written a whole list of people that we need to interview on what their topics were.
Dan: [00:25:44] Ah excellent.
Jacinta: [00:25:45] And I’ll let you get back to your funding proposals.
Dan: [00:25:47] Yeah. I’m just holding thumbs at this point,
Jacinta: [00:25:52] which for those not in South Africa means crossing fingers. That’s the very South African phrase.
Dan: [00:25:57] Oh right, yeah! I alway forget that that’s a South African thing.
Jacinta: [00:26:00] Okay. Well, that’s it for today. So thanks very much for listening and we hope you’ll join us again for the next episode of The Cosmic Savannah. You can visit our website, thecosmicsavannah.com where we will have the transcript, links and other stuff related to today’s episode. You can follow us on Twitter, Facebook, and Instagram @cosmicsavannah. That’s Savannah spelled S A V A N N A H.
Dan: [00:26:22] Special thanks today to Kelebogile Bonokwane for speaking with us.
Jacinta: [00:26:26] Thanks to our social media manager Sumari Hattingh and all the Cosmic Savannah volunteers.
Dan: [00:26:31] Also to Mark Allnut for the music production, Janus Brink and Michal Lyzcek for photography and Lana Ceraj for graphic design.
Jacinta: [00:26:38] We gratefully acknowledge support from the South African National Research Foundation, the South African Astronomical Observatory and the University of Cape Town Astronomy Department to help keep the podcast running.
Dan: [00:26:48] You can subscribe on Apple Podcasts, Spotify, or wherever you find your podcasts.
And if you’d like to help us out, please rate and review us and recommend us to a friend.
Jacinta: [00:26:56] We’ll speak to you next time on The Cosmic Savannah. [Music ends.]
Uh, and we also have a little discussion about photometry and spectromedy…Oh. [Laughs]
Dan: [00:27:14] Do you want to leave that in there?
Jacinta: [00:27:17] No, that can be for the bloopers.
Dan: [00:27:20] And that’s it for today. Thanks very much for listening and we hope you’ll join us again for the next step of the next ep… why is that one first?
Jacinta: [00:27:26] Cause that’s always first.
Dan: [00:27:27] Is it? It feels like it should be last.
Jacinta: [00:27:29] No, we have it again at the end. “We’ll speak to you next time on The Cosmic Savannah.” Don’t question the method now! We’re three seasons in! [Laughing]
Dan: [00:27:40] I was like, this doesn’t make sense. It seems so final!
Jacinta: [00:27:41] It does, doesn’t it?
Dan: [00:27:43] What’s TikTok? Should we join TikTok?
Jacinta: [00:27:45] I don’t know Dan.
Dan: [00:27:47] I don’t know. I’m 36 now.
Jacinta: [00:27:49] Yeah, I’m not going to say how old I am, but I’m a bit younger than you.
Dan: [00:27:53] Not far. [Laughing]