Science Friday - The Black Hole At The Center Of The Galaxy, Shipwreck Microbes. Oct 16, 2020, Part 1

Episode Date: October 16, 2020

The 2020 Nobel Prize winners have been announced, and among them is UCLA astronomer Andrea Ghez, who split the prize with Roger Penrose and Reinhard Genzel. Ghez, also the fourth woman to ever win the Physics prize, won for her 1998 work that resolved a decades-old debate among astronomers: What lurks at the difficult-to-observe heart of the Milky Way? After innovating new ways to peer through the obscuring gas and dust, Ghez and her team observed the orbits of stars around the galaxy’s seemingly empty center—and found they fit a pattern explained so far only by a supermassive black hole of at least four million times the mass of our Sun. In the decades since, she and her team have investigated the gravitational forces of the galactic center, and how well they match Einstein’s theory of relativity. (So far, her team has concluded, Einstein seems mostly right, but his theories may not fully explain what’s going on.) Ira talks to Ghez about how our understanding of the center of the galaxy has evolved, plus the questions that still puzzle her. Plus, off the coast of North Carolina is a large lagoon called the Pamlico Sound, which supports a diverse ecological landscape. It’s also home to the Pappy’s Lane Shipwreck, a World War II vessel that’s partially submerged in the Sound. This wreck has become an artificial reef, and the life that surrounds it, big and small, is ripe for research. Just as humans have their own microbiomes, which are different for everyone, shipwrecks have microbiomes, too. Scientists study them to better understand what’s living on these sunken ships, and how to preserve them for future generations. While the vessel is not a natural part of the Sound, its role as an artificial reef makes it an important part of the ecosystem. By better understanding its microbes, scientists hope to help preserve this non-renewable cultural artifact. Joining Ira to talk about the marvelous microbes on the Pappy’s Lane Shipwreck is Erin Field, assistant professor of biology at East Carolina University in Greenville, North Carolina.  Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

This is Science Friday. I'm Ira Flato. About later in the hour, we'll talk to astronomer Andrea Gess, whose hunt for a supermassive black hole at the heart of our galaxy, won her part of this year's Nobel Prize in Physics. But first, as the pandemic extends into the fall of 2020, we are learning more about the long-term effects of the virus on people who have been infected with COVID-19. For example, some people report experiencing a variety of unrelated symptoms,

from brain fog and tiredness to heart, lung, and gut problems for many months after being declared virus-free. Doctors and scientists don't yet quite understand why these symptoms persist, and in the absence of a clear diagnosis, people with the condition have themselves named it Long COVID. Here to talk about that and other news from the week is Sophie Bushwick, Technology Editor for Scientific American. Always nice to have you back, Sophie. Thanks, Sarah.

Tell us about long COVID. Have we come up with a definition yet for what it is? So long COVID refers to the patients who after they recover from an initial bout with COVID continue to have symptoms, or they might feel that they don't recover in the first place and that they continue to have issues. So data suggests that about 10% of COVID-19 patients still feel unwell after three weeks, and then a smaller group, about 5% of patients can be sick for months. Some people who have gotten sick towards the beginning of the pandemic have been sick for seven months,

have been having these symptoms that can include, as you said, problems breathing, heart issues, problems with their gut, and as well as neurological issues such as brain fog and forgetfulness. And we really don't have any theories as to why the symptoms are so different? So far, researchers are just starting to really dive into this because this is such a new disease. everything is fresh and they're still looking for theories about this. One current theory is that there is a set of several different syndromes that is associated with COVID and post-COVID recovery and that perhaps people are afflicted with multiple of these syndromes at the same time. So at first, they might have an issue with their heart and then maybe those symptoms abate and then a different

set of symptoms arises neurologically, for example. And what should patients who suspect they have long COVID do? So data is really valuable now. If patients are continuing to suffer from these symptoms, logging what they're feeling and keeping track of these symptoms could be very helpful for health researchers, as well as the patients, the medical system needs to be able to support them. So it's very important that doctors, for example, not dismiss ongoing symptoms in COVID patients and that they take this seriously. And the medical system needs to be able to offer support to people because like I said, 5% can be sick for months, which sounds like a small number, but about 38 million people all over the world have COVID, and 5% of 38 million is a pretty big number. Yeah, lots of people.

Another thing we're seeing as the pandemic continues, a few cases of coronavirus reinfectioning, including the first instance reported here in the U.S. this week. That's right. There was a case in Nevada where researchers have found that a patient had indeed been reinfected. actually became sicker the second time he was infected with the virus. But I would like to emphasize that this is a very, very rare occurrence. This man adds to the number of total patients, but there's about five patients worldwide who have been definitively proved to be reinfected. And as I mentioned, that's out of 38 million. So the chances of reinfection at the moment seem to be less than one in a million. When you say definitively proven, how do we know a person is really reinfected?

So this is kind of interesting. Basically, researchers need to have sequenced the genome of the virus that the patient had originally, and then they need to sequence the genome of the virus that the person gets on reinfection. And then they need to be able to prove that those two genomes are different enough, that it's not just the same infection flaring back up. So this is actually tricky, right? Because when a patient comes to the hospital with COVID, the first instinct is not necessarily, oh, let's sequence the genome of this virus. So the number of people who are eligible for this kind of testing is not super high, which means there could be other cases we're not aware about, but it does seem like those cases would still be extremely rare. Really interesting. Let's move on to some other topics in the news. Really a weird one. Researchers say that they calculate that the probability we are living in a simulation is 50-50, a coin toss. Really? Really. I really enjoy this type of speculation. Back in 2003, a researcher suggested, how would we be able to tell if we're living in a simulation? Let's say we have that there exists a very technologically advanced society, and they've got near infinite computing power.

They could make a really, really detailed simulation of real life that existed only within the world of this computer, and they would simulate the laws of physics and the behavior of life forms in this simulation. And if your computing power was high enough and the simulation was good enough, it would seem a lot like real life. So how can we tell whether we're living in base reality or we are actually conscious beings being simulated by this unfathomably technically advanced civilization? Yes, because if you're inside the box,

how do you know you're inside the box? Exactly. Well, one suggestion is, again, I said near infinite computing power. So if you have this computer trying to simulate reality in our world, scientists sometimes have to kind of cut corn when they're simulating something incredibly complex, they can't get the exact right answer, but they can get an approximation of the right answer. And when you apply the idea that some of the laws that govern us, some of the rules of our world might just be approximations and not exact,

then you might be able to run certain quantum experiments that might have little flaws in it or little approximations where you'd expect exactitude. And by looking at that, researchers might be able to tell, oh, this is the sign that we're a simulation. On the other hand, it could just be that that's the way reality works and our models of reality aren't good enough to cope. We don't have quite the right idea yet. So it's the kind of thing that's very, very hard to definitively prove or disprove. Yeah, it gets back to my talking about always looking for new laws of physics we haven't discovered yet. Exactly. Yes, it could just be there's some law of physics that we either haven't discovered or we have the wrong idea about we don't have the numbers quite right.

So it's the kind of thing that's a lot of fun to speculate about, but I don't think that we're going to ever see a paper come out that's going to say this is definitive. We are a simulation or not. Yeah, not too soon. Speaking about things that are fun to speculate about, that includes, I understand, trying to build a room temperature superconductor. There's news on that? Yes, there is. So a superconductor is a substance that can conduct electricity very fast and efficiently. It doesn't lose any of its MFPFRAC. to heat dissipation, and this could make for super-fast electronic devices that never overheat. But the problem is, in order to get a substance to the point where it's a superconductor, researchers typically have to chill it to very, very cold temperatures, and that's not super practical for everyday use. So in recent years, researchers have been toying with taking materials and putting them under extremely high pressures, and when they do that, they've been able to maintain

superconductivity at temperatures that are relatively warm but are still pretty cold. I think up until now the best they could do was about negative 13 Celsius. But most recently, they've managed to create a superconducting material at 15 degrees Celsius. That's about 59 degrees Fahrenheit. So that's the kind of temperature that's pretty easy to maintain. The only issue is there's a bit of a catch. This only functions at pressures about as high as you'd find in the center of the earth. Small detail, right? A little bit, yeah. Yeah, you don't want to have to operate a computer at that kind of pressure. Yeah, well, as we say in the science business, more research needs to be done, right?

Absolutely. And I think that this finding, though, does give rise to new ideas about the type of material. So this particular material is made of a combination of hydrogen, sulfur, and carbon. And it suggests that maybe different combinations of this material or compounds of hydrogen and two other elements. could have different properties. Researchers can now start testing a lot of those and see if any of them can just keep functioning at slightly less extreme pressures. Fun stuff. Let's move on to the election, the 800-pound gorilla in the room. While we've been focusing on the presidential election, there are congressional seats to consider. And there are a few doctors running for those seats this

year during a pandemic, right? That's right. There's at least two big races, one in Arizona and one in Kansas, where doctors have thrown their hats into the ring. And one thought is that in the middle of this pandemic, when we're relying on health care workers and doctors to keep people safe and they're being seen as heroes, it is possible that public opinion could help doctors who are running for a political office. So in Arizona, there's a race between Dr. Herald Tipperenni and David Schweikert. Tipernini is a Democrat. Schweichert is a Republican, and he's also the incumbent.

So Dr. Tipernini, she would need to win a race that's tough to win against an incumbent. But she thinks that being a doctor and having a scientific background could help her in this race. You know, I've seen this in a couple of other congressional races. In my own little world here in the East Coast, I've seen running as a doctor, the candidates thinks that that is a big plus because, as you say, people trust doctors more than they do politicians, especially now. That's exactly right. But it's actually interesting. In some cases, you have doctor versus doctors. So there's a contest in Kansas right now where there's two doctors running against each other. Dr. Roger Marshall is a Republican, and Dr. Barbara Ballier is a Democrat. But despite the fact that both of them have medical degrees,

they have different, very different opinions on climate change. Dr. Marshall, the Republican candidate, has said that he is not sure that there even is climate change, and he said that as recently as 2017, whereas Dr. Bollier has stated that climate change is an issue for her. And it's certainly going to be an issue in this election for a lot of people. For a lot of people, climate change is an extremely important issue. Yeah. Finally, there's a wonderful space first coming up next Tuesday, a return sample mission from an asteroid. First time we've ever tried that? This is very exciting.

The Osiris Rex space probe is going to be taking a sample from the asteroid Benu and then bringing it back to Earth, which is very exciting. Going to bring it back. It's going to hang around for a couple of years. And this is going to be televised so people can watch it as it's happening. I find that really cool, don't you? Oh, absolutely. I mean, this is a groundbreaking, an asteroid breaking first.

That's a joke from you. That's good. Thank you. Thank you. I try. But this is going to be a very exciting thing to watch. It's on Tuesday. I think that they're starting the televised broadcast around 2 p.m. And then I think they're expecting to be able to actually scoop up the sample at about 6 p.m. East Coast time. Sophie, you're always bringing us exciting stuff to talk about. Thank you for taking time to be with us today. Hopefully we'll be watching. Thank you. I'm definitely going to watch. Sophie Bushwick, Technology Editor for Scientific American. We're going to take a break. And when we come back, how do you find a super massive object that knowing,

can see. Nobel Prize winning astronomer Andrea Gess weighs in on Science Friday from WNYC Studios. This is Science Friday, I'm I Refleto. If we could view it from the outside, the Milky Way would look like many other galaxies,

a beautiful spiral of shining stars and glowing dust and gas. But what's at the very center? If your answer is a super massive black coal, the mass of four million suns, well, you You've probably heard something about the work of UCLA astronomer Andrea Gess,

whose research, more than 20 years ago, helped pinpoint the existence of an invisible, compact object at the heart of our Milky Way. The astronomers call that likely black hole Sagittarius A-Star. After we learned there's a hole in the center of the sea of stars, we wondered how it could help us understand the evolution of our galaxy and our universe. Turns out, Sagittarius A-Star can even help us test Einstein's general theory of relativity. But don't take my word for it. Dr. Andrea Gess, who shares the 2020 Nobel Prize in Physics for this work, is here with me today.

Congratulations, Dr. Gazz. Thanks so much, Ira. Take us back to the 1990s. Why was this question about what's at the center of the Milky Way such a hotly contested one? Because there was a suggestion that, incredibly massive, or what we call supermassive black holes, might reside at the center of the galaxies. So this builds on the concept of black holes, much smaller black holes, which theorists had long suggested existed as the end state of how massive stars end their lives. And we had plenty

of observational evidence. But what was mounting was unusual activity at the center of galaxies. And so while it wasn't predicted theoretically, there was mounting observational evidence that there might be a much more massive cousin to what we call ordinary mass black holes. And so you had to go out and find a way of collecting evidence for that, Ben, right? That's right. And in fact, the idea of these supermassive black holes came from a small set of galaxies in the zoology of galaxies, known as active galactic nuclei. And these are galaxies that have very, a lot of activities coming from their centers. But about 50 years ago, it was suggested that maybe all galaxies harbor supermassive black holes and that most galaxies have black holes that you could say are on a diet because you can't see a black hole directly. So what you do see is the light

that's associated with mass falling in towards the event horizon. And if you're going to ask this bigger question of whether or not all galaxies harbor supermassive black holes or really more fundamentally do these supermassive black holes exist, our galaxy is the best place to look, simply because it's the center of our galaxy is the closest center of a galaxy we'll ever have to look at. The next closest galaxy is a hundred times further away. And you thought maybe we can find a way to watch the orbits of stars around where this black hole should. be and get some confirmation, correct? That's right.

So the question is, how do you prove that there's a supermassive black hole at the center of the galaxy and the challenge is to get direct confirmation? And so what we did is to look at how the black hole might influence things around it. So stars orbit the center of the galaxy for the very same reason that planets orbit the sun. It's the gravitational influence of whatever is inside. So what you do learn from orbits is how much mass. is inside the orbit of the star that you've measured.

So to show that there's a lot of mass inside a small volume, the key is to find the stars that are as close to the heart of the galaxy as possible. And that's what led me to want to work at Keck Observatory. So Keck is the largest telescope in the world. It's co-owned by the University of California and Caltech. And it's located out in Hawaii. And if you have a large telescope in principle, you can get very detailed picture, which should allow you to see the stars at the heart of the galaxy.

But the challenge is the blurring effects of the Earth's atmosphere, which make images fuzzy rather than sharp. So I've spent the last 20 years of my career or even more than that working on techniques that overcome the blurring effects of the Earth's atmosphere. So you can get these very sharp images and then track and measure how these stars move. So these stars motions give us the ultimate proof of the supermassive black hole. Do you feel vindicated after 20 years of looking for all this data? Oh, I do. In fact, I do all the more because, in fact, my very first proposal to use the telescope was turned down because people didn't think our technology would work.

And even if it did, that we wouldn't see stars. And even if we could, we wouldn't. we wouldn't see the move. So as is often the case with science, there's usually a lot of naysayers. So it is amazingly gratifying to have had this work turn out to be so productive. And in a fact, in a way that we could not imagine when we first started this project. In fact, when I first proposed it, I thought it would only be a three-year project. And it turned out to be so much more powerful than I imagine.

imagined, we just kept going with ever more powerful tests of what's at the heart of our galaxy. Now, you share this half of the Nobel Prize with Dr. Reinhard-Genzel of Germany's famous Max Planck Institute. What did you two do differently? In fact, were you sort of competitors at this? Absolutely. We've been competitors for the last two decades. But it's been a really productive competition, these measurements are very hard to make. So there's tremendous value in having two groups that independently demonstrate that what we're finding is real. It's also true that there's nothing like a little competition to keep you motivated and working hard. And the two groups have constantly look carefully, scrutinized each other's work. So the other group is always going to find

your mistakes. And I think the true beauty of having independence is that it allows independence of thinking. These measurements are associated with techniques that have never been used before and approaches to these measurements in terms of the methodologies that also had to be developed. So having the two groups think independently, I think allowed much more creativity. Although, of course, we're constantly learning about each other's work. So while we're independently, we're always publishing our thinking at various points and going to conferences. So there's sort of a scaffolding of understanding and borrowing from the other team. But I have to say there's something that's been so constructive about two teams going at this from different perspectives.

You know, of course, the Nobel Prize has only given out to a maximum of three individuals, But as you say, there are whole teams of people working on these things. Absolutely. So I'm really fortunate to be working with a team of people. There was a team of three in the beginning. And now I have a collaboration that I lead that has about 30 core people. And that's simply because the – Wow. Wow.

So it's like running a little small business. And I'm – That's a lot of pizza, isn't it? Late at night. It's a lot of pizza. And it's just a pleasure because, of course, everybody brings their own expertise or the students bring their own perspective and own questions. And as this project has gone on, it's become richer and richer.

The technology has advanced in a way that's allowed us to actually not only answer the original question that we were trying to get at, but has actually presented us with more questions than answers. For instance, we predict that. that black holes create this very extreme environment around them. They have strong tidal forces. So that means that if you were to fall into the black hole, your feet first, your feet would experience much higher gravity than your head.

So the anticipation of that extreme environment is that you shouldn't have star formation happening near the black hole because star formation requires a pretty gentle environment that should allow the collapse of clouds. And these fragile clouds would be expected to be torn apart. And yet, the dominant part of the population that we can see are young stars. So I like to call this the paradox of youth. How do we get star formation happening near a black hole? Another example of this is we anticipate that there should be lots of old stars surrounding the black hole.

Old stars, by the nature of the fact that they've been around for a very long time, interact with the environment and should sink to be towards the most massive object in the system, means black hole should be surrounded by a population of old stars. And yet there's actually a dearth of the old stars. So there's a question of where are the old stars? And then the last, and perhaps my most favorite, is a population of objects that are being tidily distorted as they make their closest approach to the black hole. So this is rather amazing, given how far away we're looking, that we can actually see the

evolution of these objects as they come towards the black hole. they get stretched apart, and then they become much more compact as they move away. And these objects have to be about a factor of a hundred times bigger than anything we had anticipated at the center of the galaxy. So, you know, what in the world are these objects that are being tidily torn apart? So just three examples. Yeah, it seems like we have so many unanswered questions about black holes. And I want to ask you now that I'm glad I have you here because I've been reading recently

about one of the theories is that black holes left over from the Big Bang could have been the source of the dark matter we have in galaxies now that we don't know what it's made out of. What is your take on that? Well, so there is an interesting question of dark matter. And there's a couple of things you can ask about dark matter leftover from the original process of galaxy formation. Today, we think that the dominant thinking in the field of astrophysics is, that dark matter is probably in the form of elementary particles rather than the big black holes,

but there's still controversy surrounding it, but the dominant thinking is around the particle idea. But it is true that the black hole, the central black hole, should be surrounded by a sea of these dark particles. And in fact, that's one of the other things that we're attempting to investigate is to discover if we can detect the presence of dark matter surrounding the black hole. Because those particles like the old stars should be populace around the black hole. That's fascinating. Let's talk about relativity. Your research looking at the movement of one star around this black hole concluded that Einstein's general theory of relativity, explains it better than Newton.

Is that sort of similar to mercury going around the sun? It's related in the sense that Einstein's ideas predict this mixing of space and time. And there are various imprints of that on things that pass through this environment. What was actually being tested at first was the impact of that mixing on how photons or light particles travel from the object or SO2, my thing. favorite star to us. And those photons actually have to lose energy in order to crawl out of the strong gravitational field of the black hole. So that was what was tested initially. And now what we're all going after is what's known as the procession, which is what we saw with mercury going around the sun. And of course, what we're looking for is how does gravity behave

around a supermass of black hole. That's particularly intriguing because black holes in a sense represent the breakdown of our understanding of physics, the fact that we don't know how to make the field of general relativity, which is what Einstein was so famous for, describing gravity,

work together with the field of quantum mechanics, the field of things that are very small. And of course, black holes are both. So what we're looking for, as we probe how gravity operates, around these objects is really a clue for that breakdown, because that's really the way, we're assuming that this is the path forward

to understanding ultimately how gravity can come together with quantum mechanics. I'm Irafledo, and this is Science Friday from WNYC Studios. You mentioned your work at Hawaii's Keck Observatory in Monacoa, which was interrupted by Native Hawaiians protesting, the construction of the 30-meter telescope, at the time you acknowledged that the lost time was irreplaceable to your research, but also that the mountain's culture and spiritual significance needed to be respected. We have talked in the past to Native Hawaiians

who'd like to have more sovereignty in resolving this conflict. Do you see a way forward with this? I do, and I think it's incredibly important. that we have these hard conversations. In a sense, it's almost like the discussion that we had a moment ago about competition. Having two disparate points of view is ultimately the way of finding a more creative solution. So I guess coming from this position of 20 years of competition and seeing that arriving at better science, what I hope ultimately is having a better collaboration between the scientific community and the Native Hawaiians will help us arrive at a solution that's right for all of humanity.

Do you think the public gets this? Do you think they understand what's going on with black holes and your work? I think black holes are fascinating to the public. For some reason, unlike so much of physics, black holes capture people's imagination. I mean, of course, I think it's helped by science fiction, where people play with, you know, all sorts of, you know, concept of space travel. But, I mean, it's one of the things I really like about working in this field is that you can capture that, that hook that people have or that curiosity about black holes. So where do you go from here, you've won the Nobel Prize. What's next on your agenda? Oh, gosh, it's doing science. I mean, in my, for me, it's never doing this. It's not about prize winning, but rather about scientific

exploration. So there's so much more for us to do in terms of understanding gravity and understanding the astrophysical role that black holes play. And then, you know, quite frankly, working through these issues associated with the 30-meter telescope, which, you know, they're complicated, they're thorny, and in some sense you need people with the, I don't know, the scientific stamp of approval that can be viewed as leaders. Well, that's a good place to end it. I hope that all comes to pass, Dr. Gess. Thank you for taking time to be with us today. And congratulations again to you and all your staff.

Thanks so much. Thank you, Aura. Dr. Andrea Gez is a professor of astronomy at the University of California in Los Angeles, where she also directs their Galactic Center research group. When we come back, we'll talk about the marvelous microbes that live on shipwrecks. We want to control the growth of microbes that could cause damage. But we also want to maybe promote the growth of bacteria that can help preserve these wrecks. Stay with us. We'll be right back after this short break. This is Science Friday.

I'm Ira Flato. Let's take a trip, shall we? We're plunging into the Pimlico Sound, a large lagoon off the coast of North Carolina. We're not here to look at fish or plant life. We're here to check out a shipwreck, specifically to learn about the microbes that live on and around this wreck. You see, just like you and I have our own microbiomes, which are different for everyone, shipwrecks have microbiomes too. And scientists study them to better understand what's living on these sunken ships and how to preserve them for future generations. We're looking for a shipwreck known locally as the Pappy's Lane wreck.

Ah, there it is. There it is, along with our guest, Dr. Aaron Field, Assistant Professor of Biology at East Carolina University in Greenville, North Carolina, who is here to tell us all about the marvelous microbes that live on our shipwrecks. Welcome to Science Friday. Thanks for having me. Nice to have you. And just a note, this segment is being recorded with a live Zoom audience.

Yay! Thank you, thank you, thank you. Great to see all of you. Science Friday listeners can ask their own questions about shipwreck microbes. Learn more about joining a few. future live recording at ScienceFriady.com slash live stream. Hope you enjoyed our radio theater swim, Dr. Field. Yeah, I'm really excited.

I'm excited to talk about the shipwreck microbes and hear everyone's questions. So you've swam out to this shipwreck before, I imagine. I have, yes. It's a wonderful wreck in North Carolina, as you mentioned, the Pamlico Sound. And so the ship itself is about 50 meters long. It's steel hulled, so it's basically made of steel and iron. iron. And it was originally thought to be a World War II war boat built in the 1940s. It then transitioned to life as a barge. And it ran aground in the 60s and it was abandoned there. So now it is just

the staple in the community in Rhode Anthe. And it's not in very deep water as you can sort of wade out to it, can't you? Correct. So it's a shallow water shipwreck. So you can wait out to it. If you go out there, you will find people kayaking around there. You'll find fish. You'll sign snorkelers. Yeah, it's a good location to go. Let's talk about the microbiome that's on the ship. How do you actually collect microbial samples from a ship? Yeah. So what we did was we went out to the ship itself and we were able to collect a few different sample types. So first, there are what we call shipwreck debris pieces. So these are pieces of the wreck that have already deteriorated and fallen off the intact part. And so we can collect those. And then we can scrape those. And then we can scrape

off the surface gently and collect the microbes that are on that. We were also able to drill pieces from the ship hull itself, both where it's submerged in water but not buried. And we also were able to collect drilled shipwreck pieces below the sediment line where they had just dredged. So we have a few different pieces that we collected as well as sediment samples in the area around the wreck and the water as well. Are the microbes different wherever you drill or scrape? Are they different kinds of microbes? Or are they all the same? Yeah, so that was one of the questions we really wanted to answer

when we were looking at this wreck. So when you think about each shipwreck, everyone is unique. Everyone has its own story. It went down at different times. It was built in different places. It's in its own environment now. But even within one shipwreck site, we can see that there are differences.

So the microbiome would be one example. So the microbes in the sediment nearby versus the water nearby versus the shipwreck itself were all. different. And really cool was if you look at the shipwreck itself, there were different microbes in different places on the wreck. So much like you think about your own microbiome, you have microbes everywhere, but the ones in your gut are different than the ones on your skin. The same thing happens on these shipwrecks. Interesting. So what do you hope to do with this better understanding of what microbes are on the shipwrecks? Shipwrecks are fascinating. And the microbes can both be

helpful and hurt the shipwreck environment. So when we look at microbes associated with these wrecks, some can contribute to what we call bio-corrosion, so they will help deteriorate. So organisms such as iron-oxidizing bacteria or bacteria that eat iron and make rust, that can actually cause deterioration of these wrecks. And we're trying to preserve these historical artifacts. So we want them to be maintained and preserved. So we want to control the growth of microbes that could cause damage. So we would like better early detection methods to know if they're there so that we can better design our mitigation methods for preservation. But we also want to maybe promote the growth of bacteria that can help preserve these wrecks. So there's also microbes that will make a biofilm. They'll

attach and make this kind of protective layer that helps protect the wreck from corrosion by the ocean itself. What could preservation technique look like? I mean, how do you preserve a ship sitting there in shallow water. Yeah, that's a great question, and that's something we're really still working on. I mean, we haven't thought too much about how microbes really contribute to the deterioration. We have not been able to look at that enough. So I work with maritime archaeologists that are really excited about learning how they play this role so that we can design management strategies. Because like you said, it's a huge ship at the bottom of the ocean, so how do we protect it? And so that's something we're working on. We are on Zoom, live Zoom audio, and we have a question

from Ken from Bloomfield Hills, Michigan. Go ahead, Ken. Well, good morning. I was curious as to what depths will you find microbes on shipwrecks. Good question. Yeah, it's a great question, Ken. If we look at water depth, there are microbes just about everywhere. So when a ship goes down, whether it's shallow water like we're looking at in Rodanthe or it's really deep, say in the Gulf of Mexico or somewhere else, there will be microbes there. They are found in the water. They're in the sediment. And when that ship goes down, it becomes a new source of space, a place to live. All these microbes are competing for space and nutrients, so they've just found a new place that they could live. And then they will attach and start building their own community. Is this a new concept about collecting

a ship's microbiome? Because I don't remember hearing about this many years ago. Does this mean the location of a wreck impacts what microbes are on it? I mean, just learning all about this seems kind of new? Yeah, it is new. So the maritime archaeologists here at East Carolina University have been studying Rex for, you know, many, many years. And they know that microbes can contribute to some of these processes, but it's never really been evaluated. You know, it's a difficult to sample. But yeah, it's a new area that we're really trying to expand into. When we say microbes or you say microbes, does it mean a lot of different kinds of microbes? I mean bacteria, viruses. What makes up microbiome. Yeah, that's great. Yes, is the short answer to that. And so we have bacteria. We'll have

archaea. We'll have viruses. Basically, when we say microbe, I teach my students, the simplest term really is anything you can't see by the naked eye. So all those organisms that you can't see without a microscope. And so these microbes are coming in contact with other aquatic life that lives in the ocean there, right? Yeah, they absolutely are. And so one of the, One of the things I think is so fascinating about shipwrecked microbes is, you know, a ship will go down, and the microbes will be the first to attach most likely. You know, they have a new home that they can take advantage of. They start building a community, contributing to carbon cycling and nitrogen cycling and aiding the entire biological community in the ocean. And then as they do that, this becomes an artificial reef.

And so now other organisms can come in. We have the fish and turtles and corals and oysters that all come in and make a community. So these wrecks don't just have a historical relevance, but really, they also have a really important ecological role. Interesting. Let's go to Zoom again for a question from listener Abby about different kinds of wrecks. Go ahead, Abby. Hi, Dr. Field.

Have you noticed any differences in microbiomes of wrecks that are easily accessible by people versus those that are not? And if so, what do people introduce to the microbiome of a shipwreck? Great question. Yeah, that is a great question. You know, we haven't had the opportunity to compare the microbes associated with one rec versus another yet. That's something we really want to do more of because it is such a newer, younger field. But I would absolutely expect that the microbes will be different.

If the microbes on one shipwreck are different in different places, I would expect that microbes between different wrecks or different depths would absolutely. be different. So we have microbes that live everywhere, but it doesn't mean that the same microbes live everywhere. And so that's really important thing to keep in mind. Do you think that you are leaving a little bit of your microbiome behind when you go to that shipwreck? Yeah, that's a great question. So we really work hard to wear gloves and protect. It's interesting because we're protecting the wreck from us because we have microbiome and we don't want it to affect our samples. But absolutely. I mean, if you go to a shipwreck and you're scuba diving and you're exploring or you're snorkeling and you touch it and you do things, absolutely, you can introduce a new microbiome to that wreck.

And it's something that, you know, we haven't had a chance to look at, but absolutely. You know, studying the microbes on a shipwreck is not something you see in a catalog of a university when you go to apply to go to school there. What got you interested in studying shipwrecks? Well, the first thing is shipwrecks are just so cool if you have the opportunity. you can't, you know, say no. For me personally, being in North Carolina, we have thousands of shipwrecks across the coast. And so you have that connection to it already. And I have been studying iron oxidizing bacteria for many years now. And these are microbes that live on steel and iron-based sources. So I thought, why wouldn't they be on a steel-hold shipwreck in the ocean? You know, these organisms live

in the ocean as well. So that was one of the things that got me really excited about it. And then I had the opportunity to work with Nathan Richards here at ECU in the Meritama Archaeology program. And he was also very excited to learn about how microbes may be contributing to bio-corrosion or deterioration of these wrecks. So we teamed up and got started. We have a question from your neighborhood. Listener Terry from North Carolina's Outer Banks is waiting with a question. Hi, go ahead, Terry. Hi, thanks for taking my question.

My question is about the salinity because I know the Pamlico is, the salinity is. variable. And I was wondering if that salinity played a big role in the difference in the microbiomes from the wreck to the sediments to the water. That's an excellent question. And absolutely, salinity plays a very large role. It does for microbes in general. Microbs usually have a range that they can live in when it comes to salinity. And you're right, this one fluctuates in the Pamlico sound. And so I would expect that it would affect which microbes are there. We find a mix of microbes that you could find typically in estuaries, but that can adapt and withstand salinity ranges that do fluctuate. I would also, back to the question that was asked earlier, when you think about the

deep maybe wrecks versus here, salinity would play a role too. So if salinity and oxygen and other things are fluctuating in this estuary, it will affect which microbes are there and how they function compared to a deep wreck that maybe some of those conditions are more constant. Yeah, let's talk about a deep wreck for a second because I guess if a wreck goes deep enough down into the water, you get into an anaerobic, a lack of oxygen, right? You must find anaerobic bacteria or totally different kinds of bacteria living on those wrecks, I would imagine. Yeah, absolutely. So if we have a more anoxic environment, then we will have the microbes that can grow without oxygen. We also can find that you can have these, what we call micromesias. So we can have microbes that are

living together where maybe we don't measure the oxygen, but somebody is able to produce a little bit that the others can use. But in general, the anaerobic bacteria would be expected in maybe some of those deeper sites, particularly in the sediments. I'm Ira Flato. This is Science Friday from WNYC studios. We're talking with Erin Field, assistant professor of biology at East Carolina University in Greenville, North Carolina. And she loves to go study sunken ship. looking at the microbiomes there. I think it's kind of fascinating. Is this the ship that you're studying, is it in danger? I mean, of being washed away or hurricanes that come through there? Absolutely. So these shipwrecks, you know, they went down for a reason and that environment is

very tumultuous and is always changing. So it has been there since the 60s. So we know it has withstood some storms. But a lot of things are missing still from it, whether it's deteriorated over time. So that's why they don't have an exact identification on the wreck. It's one of the reasons. But yeah, absolutely. With stronger hurricanes coming through and storms, we could see issues with it long term. You know, North Carolina's Outer Banks where this wreck is known as the graveyard of the Atlantic. So I imagine that you have a lot of ships that you could search for or do your research. Absolutely. So that is one advantage to being here in North Carolina. There are thousands of wrecks that have gone down off the coast of North Carolina, which is why it's gotten that name, the graveyard of the Atlantic. It is a very current heavy, constantly changing sediment environment. So it's really dangerous for these wrecks. And the storms that come through, the really strong hurricanes, I've been through pretty much one a year since I moved here. And so that has always been interesting. Now I understand Pappy's Lane is now like an artificial reef where coral and things are growing among the wreck there.

Yeah, it really is an artificial reef. So one of the fun things about going to the site to sample is you're snorkeling around, you're sampling. There are fish everywhere. In fact, sometimes they come up and nibble on you to see if, you know, you taste good while you're there. And I saw so many fish. There's oysters that have started to attach in areas, so we try to avoid that part. there's a great source for them to attach and live. And so, yeah, it's become quite a ecological anchor and kind of hold spot for them. So that's the natural evolution then I would imagine of a shipwreck.

It becomes a wreck. It becomes maybe hazardous to navigation. It decays and then turns into an artificial reef. Yeah, absolutely. And to me, that's one of the coolest things, too, about this wreck is, you know, I think of it as a microbiologist that these ships go down. And they have microbes already on them when they go down, but then they become a new home for all the microbes that live in the sediments, in the water. And then they start this whole new ecological niche and location for fish to come in and the oysters to come in. And it's just a wonderful thing. All right. So tell me what you don't know and what you would like to find out. If I had a blank check right here in my back pocket, I wish I did, and I could give it to you, how would you spend it? What kind of research, what kind of technology

would you need? Yeah. So I honestly, some of the big questions I have are how different or similar are the microbiomes between these wrecks all over? We really have just scratched the surface on that. So if we want to design better strategies for preservation, we really need to understand that more. I also really want to look at can we identify the microbes that are, you know, kind of early indicators for issues for potential deterioration. So I really would like to design some sort of method that can help us with early detection. Just like with us, if we get sick, early detection is key. I think the shipwrecks are exactly the same way. Dr. Field, we have run out of time. Unfortunately, I want to thank you for taking time to be with us today. Thank you for having me.

I had a really great time talking to everybody. It was great. Dr. Aaron Field, Assistant Professor of Biology, East Carolina University in Greenville, North Carolina. And I want to thank all of you out there on our live Zoom audience. If you would like to join a future live SciFriZoom recording, this is how you do it. Join in at ScienceFriady.com slash live stream. One last thing before we go. If you were looking for our book club conversation for this week, you can find it on our podcast feed or visit our website for live stream options.

And as always, we'll put everything you need at ScienceFriiday.com slash book club. Charles Berkowitz is our director. Our producers are Alexa Lim, Christy Taylor, Katie Feather, and Kathleen Davis. And if you missed any part of this program, we'd like to hear it again. Subscribe to our podcasts, or you can ask your smart speakers to play Science Friday. I'm Ira Flato.