Episode 21: X-Ray Binaries and Astrocomms!
with Dr Tana Joseph
This week on The Cosmic Savannah Podcast we are joined by South African Astronomer, Dr Tana Joseph who is currently based at the University of Manchester, UK. Tana holds a Royal Society Newton International Fellowship and researches things called X-ray binaries.
X-ray binaries are a type of binary star system that emit X-rays. The X-rays are produced by matter falling from a star onto an exotic object such as a neutron star or black hole.
Tana also runs AstroComms, a Science, Technology, Engineering and Mathematics (STEM) consulting and communications company. AstroComms assists STEM practitioners, institutions and policymakers to effectively leverage STEM as a driver for economic and social development.
This week’s guest
Dr Tana Joseph at Jodrell Bank Observatory
Related Links:
AstroComms: https://astrocomms.com/
Featured Image:
Artist’s impression of an X-ray Binary. One star’s outer layers are being sucked towards its companion neutron star or black hole. This releases enormous amounts of energy into space.
Episode Transcript
(By Brandon Engelbrecht)
…Intro music begins…
Jacinta: Welcome to The Cosmic Savannah with Dr. Jacinta Delhaize
[00:00:07] Dan: and Dr. Daniel Cunnama. Each episode, we’ll be giving you a behind the scenes look at the world-class astronomy and astrophysics happening under African skies.
[00:00:17] Jacinta: Let us introduce you to the people involved. The technology we use, the exciting work we do, and the fascinating discoveries we make.
[00:00:24] Dan: Sit back and relax as we take you on a safari through the skies.
…Intro music ends…
[00:00:34] Jacinta: Welcome to episode 21
[00:00:36] Dan: Today we’ll be speaking to…
[00:00:37] Jacinta: today we’ll be speaking to Dr Tana Joseph from the Jodrell Bank Observatory,
[00:00:42] Dan: which is in Manchester in the UK.
[00:00:44] Jacinta: That’s right. It’s close to Manchester in the UK, and she’s going to tell us all about x-ray binaries.
[00:00:52] Dan: And we should probably point out that Tana is from South Africa originally.
[00:00:55] Jacinta: Yes. She’s from Cape town itself. So she studied here and then she went off on various adventures around the world, and now she’s a superstar astronomer and also a small business owner.
[00:01:08] Dan: And what exactly is an x-ray binary?
[00:01:10] Jacinta: That’s a very good question. So this episode is all going to be about stars and stellar evolution, which we haven’t yet.
[00:01:16] Talk to that much about, because you and I are both galaxy people and a lot of our colleagues and conferences we go to, we talk a lot to people who research galaxies, both our own and extragalactic. But every now and again, we try and talk to someone in the stellar community, and Tana is one of those. So x-ray binaries are…
[00:01:35] So the sun is relatively rare, relatively unusual in that it’s just hanging out by itself. And we in the solar system revolve around it, but a lot of stars are actually born close together and orbit each other for the rest of their lives. And this is called a binary.
[00:01:51] And then if one of these stars is very massive, it can explode in a supernova explosion at the end of its life and what’s left at the end of that can be what we call an exotic object. It could be a neutron star, which is made of just neutrons. It’s very compact, very dense, and sometimes it’s releasing pulses of radio waves, or it could be a a black hole. And then when it interacts with the companion star, so the star that’s still alive, it’s still a normal star.
[00:02:20] Some of the outer layers of the atmosphere of this star accrete, or are sucked in towards this neutron star or black hole. And as it’s doing this there, it’s releasing a huge amount of energy often at very high energy wavelengths. So like x-rays.
[00:02:37] Dan: So these compact objects are basically devouring their sibling star.
[00:02:41] Jacinta: Yeah. They don’t eat it completely, but they, they’re kind of sucking stuff off. This other star.
[00:02:46] Dan: Just nibble
[00:02:47] Jacinta: Just a little nibble.
[00:02:50] Dan: But, so there’s this event though, this, this little nibbling on your companion star. It’s very energetic, right? So that’s where these X rays are coming from. X-ray radiation is a. It’s very energetic radiation and requires quite a hot, energetic environment.
[00:03:05] Jacinta: Yeah. So you basically have to have something that’s very dramatic in the universe, something that’s very hot, very high powered. So this is not a quiet environment. Certainly life can’t exist near this interaction because it’s releasing a lot of crazy radiation. We’d be wiped out immediately. Yeah. So that’s why it’s, it’s quite exciting to figure out what’s going on and how.
[00:03:27] This interaction impacts the evolution of both the star and the compact object and what that leads to in the future. And then eventually leading all the way to gravitational wave studies.
[00:03:41] Dan: We should probably hear from Tana and she can explain this further.
[00:03:44] Jacinta: Yeah, she explains it fantastically. So let’s, let’s hear from Tana.
…Transition music…
Jacinta: Here with us, at the SARAO bursary conference, 2019 is Dr Tana Joseph from the University of Manchester, welcome Tana.
Tana: Thank you for having me.
Jacinta: Tell us about yourself.
Tana: My name is Tana Joseph, I am an X-ray astronomer and I am originally from Cape Town currently working at the University of Manchester in the Jodrell Banks centre for astrophysics. I am a Royal Society Newton International Fellow and I am really enjoying my time in Manchester. But as the nights get longer in the northern hemisphere winter, I am glad to be here in Durban in the nice warm sunshine.
Jacinta: I bet you are. So, Tana, you are originally from Cape Town, tell us about your path through astronomy?
Tana: In the mid-90s I decided that I wanted to be an astronomer and at that point, there was no SKA, there was no MeerKAT, there was no Southern African Large Telescope, the optical telescope in Sutherland that is really famous in South Africa. So that infrastructure wasn’t there and those resources weren’t there in the mid-90s. But with my parents’ support, I decided that this was going to be my career and did the necessary subjects at school, like maths and physics. I did my undergraduate degree my BSc. in physics at the University of Cape Town, I did my honours in physics there as well and then, I switched to astronomy at the masters level and by that point, we had started receiving SKA funding. They hadn’t yet chosen us as a joint host country of the SKA but we were busy making plans and building things, things like the KAT-7 telescope, that is also out in the Karoo and with the help of that funding and those resources I did masters in, actually galaxy surveys. So HI galaxy surveys, so I have a soft spot.
Jacinta: Really!
Tana: Yes, so I have a bit of a soft spot for HI because that was my first introduction to astronomy, with single dish HI galaxy surveys so I started out…
Jacinta: Me too
Tana: Yeah, so I started out extra-galactic and learned a lot, it was a really nice learning curve and that was in 2007 that I started and I also attended my first bursary conference and in those days it was not called the SARAO bursary conference it was just called the SKA bursary conference because SARAO was only established a couple of years ago, so this was more than 10 years ago and it’s always lovely for me to come to this particular conference and see the sheer number students the number of people that I don’t know is really exciting to me because things have really really grown so much and the community is increasing and it’s increasingly diverse and it’s increasingly young and that is exactly what you need for a big sort of legacy project that the SKA is set up to be. That you need to have a lot of young people to drive it forward and I have even said this about myself now, as a sort of technically an early career researcher still but I’m now on my third or fourth depending on how you count it post-doctoral fellowship and I have said to school kids when I do outreach talks, that the SKA is not actually for me. MeerKAT and ASKAP, the Australian counterpart of MeerKAT, the SKA precursors are for me in terms of my career and last night at the opening address the director SARAO, Rob Adam kind of echoed that. He said, when he sees the more senior people here, the SKA is not for them in terms of their career and even for me, I’m not as senior as a professor but I see MeerKAT and ASKAP as the workhorses, that’s where I am going to, do my interesting science and by the time SKA Phase 1 is done, I will be past my Nobel Prize-winning time because the thing about a Nobel Prize apparently is that you win it for work that you did before you were forty and I am thirty-five so I’ve got five more years and unfortunately that counts me out as SKA Phase 1, Nobel Prize-winning science, so I have to do it with MeerKAT and ASKAP.
Jacinta: I’ve never heard that rule.
5.00 min
Tana: Yeah, it’s apparently in the sciences anyway and I mean I can’t really begrudge anyone anything because MeerKAT and ASKAP are such ground-breaking cutting edge instruments there is going to be such exciting science, already, in fact, exciting science coming out of it. So now is the time to do that ground-breaking research.
Jacinta: Yeah, definitely. What single-dish telescope did you use for your HI studies during your PhD?
Tana: I travelled to the middle of France, to a tiny village called Nancay and I used the Nancay radio telescope which is quite an old telescope and has a really interesting sort of funny design. Back in the days when actually built this telescope, they couldn’t make a single dish that big, so they split it up into what would be sort of the equivalent of quite a big telescope. Much bigger than any of the MeerKAT telescope dishes, individual dishes. Not quite Green Bank telescope big, which I think is just over a hundred metres, so not quite as big as the Effelsburg telescope or Green Bank telescope but sort of on that kind of scale, but they couldn’t figure out, they didn’t have the engineering capacity to make a single dish. It’s what called a, it’s not quite a transit telescope but it’s made up of, sort of a curve bit that is a section of a sphere and then a few tens of metres away on the other side of the field is the flat steerable mirror part and then the focus is in the middle of that and it’s on a curved railway track, so if you want to really focus you, you need to actually move the focus. Yeah, it is a really interesting design and I got to go out there as a part of my masters. Luckily I spoke a bit of French because I was in a part France in a small village where no one spoke any English so everything had to be in French and I ate the most delicious authentic french food it was fantastic and every night my supervisor and I, who was a much older man had a daughter who was about my age, we would sit and have our dinner and they would give us a bottle of wine. So we would be drinking this, what I would call fancy French wine but to them, I suppose it was just plonk and so yeah it was a very sophisticated experience getting my data.
Jacinta: Wow, that sounds a lot more like a sophisticated, romantic kind of experience than I had when I was doing my PhD with single-dish telescopes. I used the Parkes telescope in Australia, in rural Australia and I spent it sort of fighting off locusts plagues. But I don’t know if they were locusts but something like that.
Tana: So we had no locusts, but there was a bit of a warning, we were told to watch out for wild boar so its proper like wooded area of France, a bit of the Asterix and Obelix kind of vibe about it. Yeah very rustic and we would, they would just like, just kind of don’t go into the woods after dark, there is known to be some wild boar around and they could seriously hurt you.
Jacinta: Oh dear
Tana: Yeah, so a very interesting experience part of thing where astronomers or other academics say oh I love to travel, I see different parts of the world and you think of France and oh it’s not that exotic but that is because you are thinking of Paris because everyone knows the Eiffel Tower, everyone knows the Louvre but very few people get to go to these tiny villages like I did. I was, yeah, I was very happy to have that experience and all that delicious food.
Jacinta: Oh yum, I am getting my tummy starting to rumble thinking about it. Okay so you started off in HI kind of astronomy area and you mentioned that you now work in X-rays, which is a different part of the electromagnetic spectrum and on this podcast, we have spoken a lot about radio astronomy because of you know, obviously MeerKAT here in South Africa and we speak a lot about optical because of SALT but we rarely have spoken about X-rays, so just tell us sort of, why X-rays and what you can see with them.
Tana: So X-rays are on the very high energy end of the electromagnetic spectrum and it is what we call penetrating radiation which, if you are familiar with X-rays from getting them at, in a medical sense at hospital to look at your broken bones, it makes sense that it is called penetrating radiation because the X-rays go right through your body and they are absorbed differently by your skin, by your muscles and by your bones and that is how you build up an image of whats inside and so X-rays coming from outside the Earth are actually absorbed by the Earths atmosphere, cause if they actually were to reach us, they would be extremely damaging and harmful to our bodies because they go right through and would be sort if you think about ultra-violet rays causing skin cancer, X-rays are much more energetic than that so it would be a real problem. So in order to observe X-rays and observe the Universe in X-rays we actually have to put the telescopes and detectors outside the atmosphere so they are satellites, they are X-ray satellites, so I get to use space telescopes in my X-ray research and another way to sort of to think about X-rays is, it comes from things that are incredibly hot so about ten or twenty million degrees and when something is very hot like that it is also an indication of something that is very energetic, very powerful very strong forces and interactions and processes so you are looking at things where there is strong gravity strong magnetic fields, all that kind of stuff. What you see in X-rays is the energetic Universe, things like black holes, neutron stars, pulsars, in particular, I study X-ray binaries which are stellar-mass black holes. So black holes that you get from exploding massive stars after they go supernova or a neutron star and they have some other star orbiting them called a donor star or companion star and the donor star actually “donate” its material to the neutron star or the black hole and that process is called accretion. So obviously the star is not actually donating it is happening under the force of gravity, the strong gravitational field and as that material gets dragged off the donor star and onto the neutron star surface or into the black hole it heats up and there is a lot of friction in there and it heats up to about ten to twenty million degrees and then it starts to glow in X-rays and that’s what we or that’s what I study or detect with my space satellites and what’s great about X-ray binaries, they are called X-ray binaries only because that’s the wavelength that they are brightest in but they are actually multi-wavelength objects. So X-ray, the process the physical process that happens in X-ray binaries give off a lot of X-rays they also give off a lot of radio waves and optical light and in some cases gamma-rays as well. So it is a nice multi-wavelength object and I actually use a lot of multi-wavelength data in the study of these and now that we have gravitational wave detectors, we are opening up a new way to explore these binary systems. So systems that would normally be dark in the electromagnetic spectrum like two neutron stars orbiting each other or two black holes or a neutron star and a black hole orbiting each other. So at some point, those sources probably use to be high mass X-ray binaries what we call High Mass X-ray binaries and there is a lot of interest now in the cool cutting edge gravitational wave community to go back, take a step back and say but where do we actually get these double black holes or double neutron star or neutron star black hole systems, you get them from X-ray binaries. So we are trying to figure out those exotic sources by looking at the progenitor sources which is High Mass X-ray binaries. So just to explain, we have this funny thing in X-ray binary research that we classify X-ray binaries by not the mass of the neutron star or the black hole but actually the mass of the donor star. So when I say a high mass X-ray, I mean a neutron star or a black hole that is in a binary with a massive star, so a star that is greater than ten times the mass of our sun. Low mass X-ray binary which is actually my main focus is where the donor star is about twice as massive as our Sun and less. So our Sun is a low mass star and then that range in between the two to ten solar mass range you would have intermediate-mass binaries but they are very short-lived and there are actually not that many so we tend to sort of not consider them when we studying populations because there are only sort of a hand full that are known. So that is how you classify X-ray binaries, not by the black hole or the neutron star but by the companion star.
15min
Jacinta: So why is it important to study X-ray binaries, in particular, low mass X-ray binaries and what are you working on at the moment?
Tana: Thank you for bringing up those questions, it’s a fantastic question. What’s great about low mass X-ray binaries is that you get them sometimes in these configurations with a black hole where you have the donor star, donating its material to the black hole and then you get these radio jets coming out and they are tiny analogues of active galactic nuclei where you have a supermassive black hole at the centre of a galaxy and it also got these jets coming out: radio jets, sometimes X-ray jets, sometimes optical jets. These tiny low mass X-ray binary analogues are called micro-quasars and what’s really useful about black hole physics or that we think how black hole physics works, is that it is scale-invariant. What that means is that whether you are looking at a ten solar mass black hole in a micro-quasar or a ten million solar mass supermassive black hole at the centre of an active galactic nucleus, the physics is the same and so the issue comes in with time scales. The bigger your object that you are looking at, so if you are looking at supermassive black hole, the longer your time scales so these AGN are bright and you can see them at really really far distances and that is really great. But the time scales on which the physical processes happen, happen on the scale of centuries and millennia and so that is obviously much longer than a human, not just a human life but a human civilization whereas the micro-quasars, the time scales involved are minutes, days, weeks, months so very much more manageable timescales. You can use the low mass X-ray binaries, well the microquasar low mass X-ray binaries, to learn about faraway distant galaxies to kind of probe the physics, the complicated physics that happens in these AGN which is very exciting. Another example again with gravitational waves, with multi-messenger astronomy why low mass X-ray binaries are particularly interesting we actually think that within in these structures called Globular clusters, which are very old, so when I say very old I mean Giga years old, some of them can nearly be as old as the Universe itself. These very old, very dense compact spherical clusters of stars that orbit galaxies so they are called globular clusters and inside them, there are low mass X-ray binaries and there is this particular kind of low mass X-ray binaries we call ultra-compact binaries with a black hole and say a white dwarf and they are orbiting each other and our calculations suggest and the theory suggests that these low mass X-ray binaries will be sources of gravitational waves that we should be able to detect, with future space-based gravitational wave detectors, particularly one called LISA. Laser Interferometry Space, I can’t remember what that A stands for now, but I got most of the way through that acronym though and so LISA will be, LISA won’t be sensitive to the same thing that LIGO is detecting, so these far away quite heavy double black holes or the neutron stars quite far away, but much lighter systems, but much closer in, so we are talking about globular clusters that are orbiting our own Milky Way galaxy and so now there is a lot of again a renewed interest in low mass X-ray binaries because of the gravitational wave connection in trying to find these systems ahead of time. So we have a priori knowledge of them in the electromagnetic system and then adding on the gravitational wave information once LISA comes online and what’s really nifty about LISA is that it should be coming online roughly the same time as SKA Phase One, which is the MeerKAT expansion. So they should be contemporaries and I think that is really going to revolutionize the study of X-ray binaries. So my talk here at the SARAO conference 2019, is about expanding, not just expanding our X-ray binary work to gravitational work but actually how electromagnetic studies of, sort of the more traditional studies of X-ray binaries can actually provide really important information going forward for things like LISA for example. One of the issues that you have with LIGO and LISA is this issue of localization. Narrowing down where on the sky these things actually came from so you can try and see if there is a galaxy there or you can try and point other telescopes at it. So if you already have information, say an ultra-compact X-ray binary, low mass X-ray binary in a globular cluster, because you saw, you can have some candidates, you know exactly where it is because you have really good localization with something like MeerKAT and once LISA is built and these things actually start giving off detectable gravitational waves in the LISA band, then we have a wealth of information leading out of that. We have a priori data then you add that to the gravitational wave data and so basically I am trying to showcase the fact that gravitational waves are what hot’s right now in astronomy but electromagnetic telescopes so traditional telescopes aren’t just useful as follow-ups but can actually be providing precursor information, so we can actually inform what they look at and what science they do because we have said perhaps a list of candidates already and I think that is really important.
Jacinta: Yeah, I was going to ask when LISA is going to be expected but you already answered that and I was wondering whether it would be coincident with the SKA, which you said that it is. So it’s just going to be an amazing revolution in astronomy and I can’t wait to hear what we are learning about. In the meantime what are you working on now?
Tana: At the moment I am on the Large and Small Magellanic Clouds so the nearest, our nearest galactic neighbours and for those of you in the southern hemisphere, of course, you can see them with your naked eye if you are in a sufficiently dark place and unfortunately if you are in the northern hemisphere you can’t see them at all, so that is a good enough reason to come to the southern hemisphere and these Magellanic clouds are really useful testbeds in terms of astrophysics because we know exactly where they are in terms of the distance but they also near enough that you can resolve the stellar components, you can study tidal interactions because these galaxies are really small compared to our Milky Way so they are being tidally disrupted by each other because they are quite close to each other but also by the much larger Milky Way so there is a lot of tidal interactions. They have a very low metallicity and I am not sure if the listeners out there know this, another quirk of astronomy is that basically in astronomy we have Hydrogend and we have Helium and all other chemical elements are called metals.
Jacinta: Chemists hate that.
Tana: Yes, my sister is studying chemistry and she gets very frustrated when I just say metals and I just throw it out there. So these two galaxies the dwarf galaxies, the Magellanic clouds have a very low abundance of metals compared to our sun or compared our galaxy the Milky Way and so in that regard that actually makes them similar the conditions in the early Universe, where there were fewer metals because there were fewer stars to enrich the Universe. So if you want to study things that are dependant sensitively on how much metal or how many metals, or the metal abundance is like for instance the evolution of very massive stars, so stars that are greater than a hundred solar masses depends very much on the metallicity components and you can study that really well in the Magellanic clouds and these very massive stars are exactly the kind of stars that we think for these massive black holes that LIGO has seen. How do you get fifty solar mass black hole because usually stars that we see in our local environment go up too about maybe forty solar masses, there are few that are bigger but we actually discovered in the Large Magellanic Cloud, a population of stars with masses of a hundred and fifty up to three hundred solar masses and that is only possible when you have low metallicities. So that is just one example of why the Magellanic clouds are a really good testbed to study the kind of things that give you LIGO sources and they also have a lot of high mass X-ray binaries which I said earlier on, would be the progenitors of these LIGO type sources. So they have everything that you need, they have the low metallicity, they nearby, they have a lot of truly massive stars, they have a lot of high mass X-ray binaries and so you can put all of that together and you can study a lot of pre-gravitational wave sources, you can study the physics of the thing that goes into that and that is what I am doing right now. So I have used the ASKAP telescope along with a huge team of people of course, all over the world to survey the Small Magellanic cloud and I also have some data on the Small Magellanic cloud from MeerKAT and we are putting all this together trying to find out as much as we can really about these galaxies and really delve into what’s in there, how did they get there, how did they grow and change an how did they change their environment and there is so much work to do which is always great because if we knew everything, we wouldn’t have scientist. So it is a really exciting time for me to finally get my hands on some SAK precursor data.
Jacinta: Yeah, I mean that is really really exciting so ASKAP, of course, being the radio telescope recently built in Western Australia, the counterpart to South Africa MeerKAT and you got data from both which is incredibly exciting. Do you think this may one day help us to understand how supermassive black holes are formed, supermassive as in millions to billions of times the mass of the Sun?
Tana: So that is a slightly awkward question actually because there is something called a mass gap, I guess you call it in astronomy. Where we know that supermassive black holes exist because we observed them and we can estimate their masses and we know that, what we call stellar mass black holes and their masses go up if you include the LIGO masses they go to just about eighty solar masses, eighty times the mass of our Sun and some as light as maybe five or six or seven times the mass of our Sun and so that leaves a huge gap their so basically between a hundred solar masses and a million solar masses there is nothing in terms of black holes and that is the region we call intermedite mass black holes amd so that is something that we think forms in the early Universe so LIGO might be able to help with that because what could be happening is you could have these LIGO sources where you have a fifty solar amss black hole and a fifty solar mass black hole and they merge and you get say a hundred solar masses but that would happen in the very early Universe and we would know more about that once we know more about where these intial heavy mass black holes came from, but it still does not really fill the mass gap in. The reason why this is awkward is because we think that intermediate-mass black holes are sort of what we call the seed black holes from which supermassive black holes via accretion. So you get this intermediate black hole, say it’s about a hundred thousand solar masses and then over time it accretes or draws mass onto it from a galaxy around it and it grows and that is how it ends up as a supermassive black hole. But we can’t find these intermediate black holes and there are a few candidates, one or two really good candidates but until we get a mass estimate, we won’t see anything and this kind of ties into, well what I will be talking about in my talk. Where we trying to, there is no consensus yet whether the Large Magellanic Cloud has a central black hole or not. So there a black holes at the centre of most massive galaxies, but these are dwarf galaxies, the Magellanic clouds so if there is a black hole at the centre, given the size of the Magellanic clouds, it’s probably going to be an intermediate-mass black hole and this is something we could possibly detect with LISA if we have stars close enough spiralling in, in what we call an extreme mass ratio in spiral. So the extreme mass ratio comes from the fact that the intermediate-mass black hole in the LMC say about ten, no say a hundred thousand solar masses and then it would be dragging in stars that are normal steller masses so between one and twenty solar masses so that is a huge ratio of masses, ten thousand versus one basically or ten thousand or hundred thousand versus one hundred thousand verses ten and that will actually, the inspiral of those stars into this intermediate-mass black hole will give rise to gravitational waves that LISA should be able to detect and what’s great about these in spiral scenarios is that the theorists are saying before they spiral in like that there will actually be electromagnetic radiation given off, from the radio all the way to the X-ray and in the southern hemisphere we have two of the most powerful radio telescopes they can easily and very sensitively observe the Large Magellanic Cloud and look for signatures of these extreme mass ratio inspirals and this is where the localization comes in, that I spoke about earlier because LISA, LISAs’ localization, the way it is being set up is not going to be that good. So we would massively benefit from having say ASKAP and MeerKAT working together finding these radio waves coming from these stars spiralling into this potential intermediate black hole in the Large Magellanic Cloud and using the very good accuracy, the spatial accuracy of these radio telescopes and then nailing down where this black hole actually is and then LISA will be able to kind of point at it much more accurately and so this is sort of the fantastic synergy of multi-messenger astronomy, where the electromagnetic components, the gravitational waves and maybe even things, we might even see neutrinos as they spiral in. Cause multi-messenger isn’t just gravitational waves and electromagnetic waves, it’s also neutrinos, cosmic waves, cosmic rays, it’s even meteorites and comets and all of that because these are all messenger particle, they all give us information about the Universe but they don’t always apply to every system. So that’s something that we hoping to start to get information on when we start observing the Large Magellanic Cloud.
Jacinta: Wow so I did, I did honours research on the Magellanic Clouds and the Magellanic Stream, but I had no idea that something so close could give us so many clues about the very early Universe, which in astronomy terms is very very far away from us so that is really amazing. But not only are you a very successful astrophysicist, you also own your own company.
Tana: Yes, I do, I started my company called AstroComms, October 2018, so just over a year ago and it was born out of all of the outreach and consulting work that I had done over the years as a postgraduate student and as a post-doctoral fellow and I realized that there is actually a demand and a value for this outside of just a strictly academic environment. So my first client was sort of a tech startup company called MeasureMatch and they hired me to give a talk about big data in science because they are also a data analytics company and their idea of big data is laughably small to what we work on in the sciences. So it was just really nice to just sort of give them insight into, give a broader context for sort of where what big data is, where is it going, what’s actually at the cutting edge. Like the work that do in the private sector is thought of as more interesting and useful but a lot of the tools that come from actually handling that come from the sciences, where we have to have the best equipment and the most optimized algorithms and all that kind of stuff and it filters down into industry so I was invited to give a talk about that and they actually paid me and it was great and I have had several other clients so far. I think my favourite one so far, they actually made me sign a non-disclosure agreement so I can’t say too much was to be a technical, basically the technical consultant for a sci-fi TV programme.
Jacinta: What!!
Tana: Yeah so like Kip Thorn, the Nobel Prize winner Kip Thorn who did interstellar, he did the black hole stuff for interstellar and made sure it was really accurate, so basically like that but without, if you don’t have a Hollywood budget, if you don’t have Kip Thorn Nobel Prize-winning money, I do the same thing but much cheaper. So yeah all sort of things like that speaking at festivals and so on. So the mandate basically of AstroComms is that it is a STEM, so the science, technology, engineering and maths consulting and communications company. So anything whether it’s just input on policymaking or for curriculum, yeah checking over curricula or curriculum development to science consulting of the media or for the creative sectors and then also giving talks, I really enjoy giving talks. I really enjoy and I am very privileged to be working with the SKA programme, as long as I have and being able to sort of showcase and highlight how far the programme has come, all those exciting things that have been happening especially in an African context. I love going out and dispelling Afro-pessimism so this idea that Africa is such an under-developed place, such a place that is somewhere where you just extract from and no one is actually building anything up and it is really great to go be able to dispell those myths and those negative connotations around Africa and say you know we are building cloud computing centre, we are on the cutting edge of astronomy, we are a global hub for astrophysics research and it’s not just in South Africa it’s actually spread around several countries across the continent and this is what we are doing, these are the fantastic young people that are coming through and being able to talk about that and I get paid to do that, I get paid to spread the word and change peoples perceptions of this fantastic continent that we are on and I think that’s something that I really try to focus on and put at the heart of the work that I do through AstroComms and people are really interested, people want to hear these good news stories. They want to hear things are changing and I always get really positive receptions about that and so I hope that there will be more gigs like that in the future and yeah just so open to all sort of ideas where technical input is needed or a science perspective is needed especially from someone still very much in the research community.
Jacinta: This is a fantastic idea, but it’s still quite unusual in our field. I think you are maybe one of, I don’t know how many but I have never actually heard about it before. How do you make this work, is it still currently moire of a side hustle that you do in your “spare time” or have you incorporated this into your sort of your, I don’t know what you would call day job perhaps?
Tana: I am that the moment, it is very much a side hustle but the idea is that I have got, I’ve set myself a fice year plan to grow the company to a point where it can be my day job and that sort of gives me exactly enough time, I think to wrap up my work MeerKAT and ASKAP because I feel now is not the time to leave the sciences, I have waited so long, the telescopes are here they doing amazing work, they are exceeding even the expectations of the people that built the telescopes. But at the same time, the work that we are doing with the SKA precursors is providing so much for me to actually talk about so when people invite me I stuff to talk about.; I can talk about the big data aspects, I can talk about the development aspects, I can talk about the political aspects because of what SKA is as well as all of this cutting edge science and engineering is also a beautiful example of science for diplomacy. Where you can pull resources and get a lot of people together from very different backgrounds, people who or places, people and places that weren’t necessarily engaged in sciences and get them all together and get them all working on a common goal that will enrich the continent but also bring a lot of opportunities to communities that weren’t always necessarily engaged with STEM and that is the kind of thing that I get to have an inside, an insiders knowledge of and sort of evangelise about and so I feel for me right now those sort of things go hand in hand. So it is a side hustle, AstroComms is the side hustle at the moment and I am starting to get to the mid-point of this five-year plan where I am going to have to, the tipping point is going to come where I am going to have to devout less time to my research and more time to the company and navigating that is going to be tricky, I’m not quite there yet. But the companies profile is being raised and I am getting a lot of interesting work and my, the people I work for are extremely supportive of this, so if I need to take time off sometimes to go give a talk that’s something they are aware of and I do a lot of my work remotely as well, a lot of it via email or on skype, telecons things like that, with the interconnectivity that we sort of, that we are in the modern-day world that is really possible. So it’s not as tricky as it would seem because people are happy to jump on skype and or record like in fact this is like a podcast that I am doing right now and I am sitting across from you, I did a podcast a couple of months ago where I was in Manchester and the guy who runs the podcast is in Pretoria and we just did the podcast over skype, we just did a skype conversation and so this is all these sorts of mod-cons make it much easier to collaborate with people all over the world, just pop something in, in an online repository or google docs, Evernote and you can really time editing sessions even if you are thousands of kilometres apart.
Jacinta: Yeah, you are absolutely right the world is a lot smaller now than we sort of think it is. So I think that this is absolutely inspirational and congratulations on getting this far and good luck in the future, you sort of paving the way for others and the rest of us to sort of go down these paths. We should go back into our session on the conference soon, but o you have any final messages for the listeners?
Tana: I would say, stay tuned to this podcast, because of they are doing fantastic work, showcasing all the cutting edge sciences that is happening, especially interviewing young people and also stay tuned because I would like to give more updates on my company and what I am doing. I would say to any young people listening that, things may sound outlandish when I decided I wanted to be an astronomer in 1995 it sounded ridiculous and outlandish but what people need to realize is, if you are in high school now, in five or ten years time, jobs will exist that don’t exist now. I remember writing a forward for a science magazine in 2013 and I used the phrase, I said something about a newfangled thing called data science and now data science is so pervasive, there is som many astronomers that go into it data science after they’ve concluded there research careers and that didn’t exist ten years ago, there was no such thing as a data scientist. Big data wasn’t something that was talked about the way it is now. The fourth Industrial Revolution, getting people really excited, things like cryptocurrency. These things didn’t exist in our parents time, they didn’t exist when I was in high school, the telescopes I work on now didn’t exist. Some of them didn’t even exist when I was already doing my post-doctoral, oh sorry my post, yeah my post-doctoral studies because MeerKAT was only completed in 2018 and I already had my PhD for five years at that point. So things change at a ridiculous pace and you will equip yourself well too not fix on something necessarily that you want to study because it might not exist by the time you finish your studies but be open-minded, be flexible, study things that are sort of future proof so things like coding, I would say languages because people often think that STEM is the way forward but you need the mix of humanity so study languages because you ever know when you might get shipped out to the middle of France to a village and someone comes to tell you to be careful of wild boars and you might not be able to understand them so it is a safety issue. So I would say, yeah study languages, even if you are South African and you want to stay in South Africa, yeah but you might have to go be a professor at the University of Venda, maybe learn some Venda because perhaps you only speak Afrikaans and isiXhosa, you never know. So yeah, just be open to learning experiences and one thing I learnt from academia is that you never stop learning, I haven’t sat in any formal exams in many years but I am constantly doing online courses, attending seminars and so on. So just never stop learning, be curious and just because your dream job does not exist now, does not mean it won’t exist in five years time.
Jacinta: Brilliant so where can people find you and your company?
Tana: They can find us on Facebook, there is the AstroComms Facebook page. They can find us on Twitter, so on Twitter, it’s Astro_Comms and then online their website is astrocomms.com and yeah, all the information you want on there, drop me a line, we respond very quickly if you have any queries about giving talks or any input that you want just to give an idea of what we do. I am always happy to talk to anyone really who wants to listen.
Jacinta: This has been absolutely fascinating. Thank you so much for speaking with us today Tana and doing it pro-bono.
Tana: Thank you again for having me, it was great.
…Transition music…
[00:42:21] Dan: Okay. Well, thank you very much for the interview.
[00:42:23] Jacinta: Yeah, it was awesome talking to Tana, she’s an amazing speaker
[00:42:27] Dan: and some interesting stuff in there. A lot of interesting details about x-ray binarys and gravitational waves, exciting projects like LISA, which is incidentally the Laser Interferometer Space Antenna.
[00:42:38] Jacinta: Ah, very good.
[00:42:39] Dan: So, an interferometer, gravitational wave interferometer, much like LIGO, which is currently operational, but up in space.
[00:42:47] Jacinta: So cool. Launching a gravitational wave detector into space.
[00:42:51] Dan: And I think that LISA is currently planned for 2034 so it’ll be, it’ll be coming online about 10 years after the first SKA phase comes online.
[00:43:02] Jacinta: So if anyone who’s listening is interested in becoming a gravitational wave astronomer, now’s the time. Well, by the time you’re trained, you’ll be ready to use LISA.
[00:43:11] Dan: It’s a very sexy science, only only in the last five years since we discovered them for the first time. Right? Yeah. I think the, the recommendation when we were doing our undergraduate was don’t you dare it into gravitational
[00:43:22] Jacinta: wave astronomy
[00:43:22] Mmhmm I heard exactly the same thing. There’s been no detections. We don’t know when the detection will be. Yeah. And lo and behold,
[00:43:31] Dan: Ah man, those guys got lucky
[00:43:33] Jacinta: They did. Well, they worked very, very hard and were very patient for it.
[00:43:37] Dan: That’s true, that’s true.
[00:43:38] Jacinta: Okay. So back to Tana’s interview. I, I thought it was really interesting to hear about microquasars, which is where the black hole or whatever it is, is accreting from the companion star and then releasing energy, jets of radiation in a very similar manner.
[00:43:54] To quasars, which is a type of AGN, and I study these AGN, these active galactic nuclei. So I was really interested to hear how we can see these, these much smaller scales and of the same phenomena as these gigantic scales with the supermassive black holes that I study. Why we want to do that is because then we can see the variation on human lifetime timescales, which is great because we just can’t live long enough to see these timescale changes in the big AGN.
[00:44:22] Dan: Yeah. It’s very cool. Like these, yeah. Like you say, micro quasars from micro black holes.
[00:44:28] Jacinta: Yeah. The universe scales. It’s really cool.
[00:44:31] Dan: Yeah. And the I, the other interesting thing obviously that Tana spoke about was her, her company.
[00:44:37] Jacinta: Yeah Astrocomms.
[00:44:38] Dan: Yeah. It’s pretty cool. I was very impressed to see how these skills were transferable to other realms of life, the interest from data scientists, big data firms and things, and in what astronomers are doing, because in a lot of ways we are moving these fields forward in not just astronomy, but in terms of dealing with big data.
[00:44:59] We’re at the cutting edge.
[00:45:00] Jacinta: Yeah, absolutely. I thought her initiative is absolutely fantastic and I hope that we see more of these sorts of things in the future, and especially giving the opportunity for those researchers who also want to do communications work to receive fair pay for that and therefore allow them to do more of this, which, which you know.
[00:45:19] Ultimately, I think helps society and the movies.
[00:45:22] Dan: Yes. Well, I mean, we all want to advise on a movie. Sit there, watch
[00:45:26] Jacinta: the dream!
[00:45:27] Dan: Yeah it is the dream. I mean, every nerdy astronomer’s dream to be the advisor on some sci-fi movie.
…Outro music begins…
[00:45:36] Jacinta: Cool. All right. Well, I think that’s, that’s it for today.
[00:45:40] Dan: Yeah. Thank you very much for listening.
[00:45:42] And we hope you’ll join us again on the next episode of the cosmic Savannah.
[00:45:45] Jacinta: You can visit our website, thecosmicsavannah.com where we’ll have links related to today’s episode. You can also follow us on Twitter, Facebook, and Instagram @cosmicsavannah. That’s Savannah, spelled S. A. V. A. N. N. A. H.
[00:45:59] Dan: Special thanks today to Dr Tana Joseph for speaking with us.
[00:46:03] Jacinta: Thanks to Mark Allnut for music production, Janas Brink for astrophotography. Lana Ceraj for graphic design and Thabisa Fikelepi for social media support.
[00:46:12] Dan: Also to Xola Ndaliso and Sumari Hattingh for transcription assistance.
[00:46:17] Jacinta: We gratefully acknowledge support from the South African National Research Foundation and the South African Astronomical Observatory to help keep the podcast running.
[00:46:26] Dan: You can subscribe on Apple podcasts, Spotify, or wherever you get your podcasts, and if you’d like to help us out, please rate and review us and recommend us to a friend.
[00:46:34] Jacinta: And we’ll speak to you next time on The Cosmic Savannah.
…Outro music ends…
[00:46:46] Welcome to episode 21.
[00:46:50] Dan: 21 today. Happy 21st you know, it’s a thing.
[00:46:55] Jacinta: Oh like 21st birthday
[00:46:57] Dan: Yeah. I don’t know if that’s every culture that, you know, every culture has a different age.
[00:47:03] Jacinta: I think it used to be you get the keys to the house.
[00:47:06] Dan: Yes. But I mean, that might be sort of British, descendants of British.
[00:47:11] Jacinta: Well, we’re all from Commonwealth countries.
[00:47:14] Dan: Well, not all of us. Just the two of us.
[00:47:17] Jacinta: Yep. Everyone in this room… Welcome to episode 21
[00:47:24] Dan: I got nothing.
