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Episode 52: Forming the Building Blocks of Life

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Scientists study meteorites, fragments of asteroids or comets that fall to Earth. Inside the space rocks, they have found amino acids, the building blocks of life. Amino acids combine to form proteins, which power life on our planet. How did these seeds of life end up in meteorites? Our guest today believes they formed under intense space conditions, particularly in the interstellar cloud. She is part of a team of scientists that re-created the conditions in a chamber using ice, low temperatures and high radiation. Their experiment yielded significant results, a residue containing the same ingredients for life found in meteorites.

Listen now as SwRI Astrochemist Dr. Danna Qasim explains how the building blocks of life may have formed in space, the role of the interstellar cloud and what the process tells us about life on Earth and the possibility of life elsewhere.

Visit Space Science to learn more about SwRI’s space research.


TRANSCRIPT

Below is a transcript of the episode, modified for clarity.

Lisa Peña (LP): A team of scientists recreated conditions in space in a chamber. They formed the building blocks of life in their chamber, an organic residue that showed a link between space conditions and the ingredients for life on Earth. We are exploring this cosmic discovery next on this episode of Technology Today.

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We live with technology, science, engineering, and the results of innovative research every day. Now let's understand it better. You're listening to the Technology Today podcast, presented by Southwest Research Institute. From deep sea to deep space, we develop solutions to benefit humankind. Transcript and photos for this episode and all episodes are available at podcast.swri.org. Share the podcast and hit that Subscribe button on your favorite podcast platform.

Hello, and welcome to Technology Today. I'm Lisa Peña. Today, we are talking to SwRI space scientist Dr. Danna Qasim. She and a team of researchers are working to understand how key building blocks of life may have become encapsulated in solar system objects, like asteroids. Part of their research involved recreating space conditions in a chamber. During their experiment, they made an organic residue composed of the building blocks of life, and they learned more about how conditions in space play a vital role in forming the material.

Interstellar organic residue

To determine to what extent amino acids formed from asteroid conditions and to what extent they were inherited from the interstellar molecular cloud, Qasim and her team simulated the formation of amines and amino acids as it would occur in the interstellar molecular cloud, forming this organic residue. She then processed the residue under asteroid relevant conditions, also known as aqueous alteration.

Dr. Danna Qasim (DQ): Hi, Lisa. Thank you for having me.

LP: OK, so there's a lot to understand here. So we want to start with a quick biology lesson. What are the building blocks of life?

DQ: The building blocks of life in the way that I describe it are essentially molecules that are fundamental to either creating or sustaining life. So for example, the muscles in our body, we eat protein to gain muscle, and protein is made up of amino acids. And amino acids are made up of amines, and so these amines and amino acids, which eventually make up protein, which then help us gain muscle, that's what we would consider examples of the building blocks of life because they're fundamental to sustaining life.

LP: Our focus today will be on those amines and amino acids. So where are amines and amino acids found on Earth? I would guess everywhere, but I'll let you tell us.

DQ: Yeah, so they're essentially everywhere out in nature. Notably, there are so there's a lot of different types of amino acids, but there are only 20 amino acids that are used in biology, used in nature. And so those amino acids are in our bodies and in our pets, everywhere out here on Earth. They're not rare here on Earth.

LP: Why do we want to know how the building blocks of life, these amines, these amino acids, originated? Why do we want to find them in space?

DQ: That's a good question, and I get that question a lot. And I'm sure a lot of my colleagues also get that question from the general public, which is like, why should people fund this research? Why should people even care about these molecules that are found in deep space and/or found here? And where do they come from?

And my take on it is, why not understand this? Why would we not want to figure out how they originated? I think of it as, if our ancestors never left their respective countries to explore the globe to explore the Americas, I truly believe that our civilization would not be as advanced as it is today. And that's how I feel about the necessity of exploring the cosmos and understanding, where did these building blocks of life we're finding certain building blocks of life that we have on Earth way out in deep space, and there could be a connection on how life would have been on Earth and these molecules that are found in deep space.
 
Telescope view of ices in interstellar clouds ESA/Webb, NASA, CSA, STScI, M. K. McClure, F. Sun, Z. Smith, the Ice Age ERS team, N. Bartmann (ESA/Webb) and M. Zamani (ESA/Webb)

An international team, including SwRI Astrochemist Dr. Danna Qasim, used the James Webb Space Telescope to achieve the darkest and deepest view of ices in this interstellar cloud known as the Chameleon I molecular cloud.

And so what's quite interesting, particularly in my research, is that, when we look for these building blocks of life, these amino acids, if they're found in an asteroid-- and asteroids are in our solar system that could mean that, OK, maybe the building blocks of life, the seeds of life, are just in our solar system and our solar system is quite unique. But if we find these building blocks of life, these amino acids, way deep in interstellar space in this giant interstellar molecular cloud, which is like the grandmother that's where a bunch of solar systems came from, then that could indicate that, oh, there's actually this frozen starter kit to life that has been distributed to potentially to other solar systems and not just ours.

And so there could actually be an indication that life may exist not just in our solar system but in other solar systems and in other planets. And I think that, exploring this, will definitely not just to itch our curiosity but to really advance our civilization as a whole.

LP: So I like the way you explain that, first of all, calling this material the seeds of life. So you're seeing the seeds of life in asteroids, and that could explain how life sparked on Earth. But another thing you said, this frozen starter kit to life could have expanded to other areas, other solar systems, other parts of space. And so I think that's really interesting that your big question is, well, if these components sparked a life on Earth, could these components also spark life elsewhere?

DQ: My heart, really, and my passion is to my expertise is really in understanding the chemistry in the interstellar cloud, which is that frozen has that frozen starter kit to life, and what I find so unique about studying interstellar chemistry is that it is really where everything came from, where our star came from, where the solar systems came from, where the planets came from. And so whatever is found there is giving us indication that, OK, those ingredients may maybe spread out elsewhere as well, and we might not be alone.

LP: So let's get into that. Let's talk more about asteroids and the interstellar cloud. OK, first of all, what role do asteroids play in the formation of these building blocks of life?

DQ: Meteorites, a lot of meteorites, so meteorites are, essentially, these dust particles that fall to the Earth from space, and they land somewhere on Earth. And people collect them, and they analyze what's in the meteorites.

And they find these building blocks of life. And a lot of these meteorites come from asteroids, and they also come from comets. But there's a lot of studies on a strong link between meteorites and asteroids. And so essentially the asteroids essentially shed the building blocks of life onto Earth every year.
 
Dr. Danna Qasim

SwRI Astrochemist Dr. Danna Qasim, along with a research team from NASA Goddard Space Flight Center in Greenbelt, Md., posits that interstellar cloud conditions may have played a significant role in the presence of key building blocks of life in the solar system.

LP: OK, so we have these asteroids in space. They are encapsulating these building blocks of life. We learn about that because, once this debris falls to Earth in the form of a meteorite, scientists are able to analyze it and find these amines and amino acids there. But your team is also taking this a step further.

So we know that these building blocks of life are in the asteroids, but your team is really looking closely at the interstellar is it cloud, singular, or interstellar clouds, plural? That's what you're really focusing on, so tell us about the interstellar cloud. What is it?

DQ: Yeah, so the interstellar cloud is this giant cloud of dust, and gas, and ice. It's located basically way past-- so the interstellar medium is located way past our solar system, and we once we all came from this interstellar cloud. So this cloud, years back, people thought, OK, there's nothing in this cloud.

But there's actually a lot of rich chemistry there, and what happens is that, eventually, this cloud will collapse under its own gravity. And this cloud will give birth to a star, to multiple stars, and then these stars will, eventually, have dust accreting around it. And then that dust kind of, simplistically, will just come together.

And then you start forming the planets and solar systems. And you have comets, and you have asteroids. And so this interstellar cloud is the grandmother of it all in that it's where everything, essentially, that we have here comes from.

LP: So is it the space between the planets and the asteroids? Is it in between the stars? Is it like what we think of as empty space in space, the blackness?

DQ: Exactly. Yeah, so interstellar, so inter is in between, and stellar is stars. So it's literally the dust, gas, and ice in between the stars.

LP: OK, there you go. Interstellar, yes, that is it's all right there. All we had to do is look a little closer at it. Yes, OK, so initially, it was thought that the significance of the interstellar cloud occurred once it collapsed on itself, but you are finding that that's not quite true. So how have conditions in these clouds contributed to the formation of the building blocks of life?

DQ: So in particular with my experiments, we found that the we looked at different types we created different types of amino acids. So we created them under interstellar-space conditions, and then we process them under asteroid-relevant conditions. And what we found was that, if you process them under asteroid-relevant conditions, it didn't matter what type of conditions we were processing them under.

The interstellar the distribution of these building blocks of life formed from interstellar cloud conditions. They didn't change. They were resilient. So essentially, what I'm trying to say is that these interstellar cloud conditions may dictate the distribution of these building blocks of life that are found in asteroids and then, therefore, found in meteorites. So these conditions may be quite influential to the building blocks that we'll be measuring from meteorites and sample return materials.

LP: OK, so when you talk about recreating this process or processing these building blocks of life under interstellar cloud conditions, what does that mean? Are we talking about a certain temperature or force? Or what do interstellar cloud conditions feel like?

DQ: Right, so it's cold. It's not cozy essentially. What we do is so there's telescopes that have collected data on what type of ices are found in interstellar clouds, including the very beautiful James Webb Space Telescope. And so what we know is that there's a lot of water. There's a lot of carbon dioxide. There's methanol and ammonia. So we took those ices. We cooled them to 10 Kelvin. And I have to do the conversion to Celsius or Fahrenheit. It's very cold. It's almost at absolute zero.

And we then bombard them with very high energy protons to simulate cosmic rays that are all over our universe, striking. There's tons of radiation in space, and so we basically irradiate these ices. And what happens is, when you irradiate these ices, they go from being an ice, like this beautiful ice, to this like gunky-like residue, origin-of-life residue. And you can actually see it with your naked eye. It looks like an oily, yellow-orangey film. And so that's how we simulate the interstellar cloud condition in the laboratory, all inside a vacuum chamber.

LP: So when you start with this ice, are there any amines or amino acids in the ice, or it isn't until it's processed through these conditions that the means and amino acids pop up?

DQ: Right, the amines and amino acids, they pop up later. So we start out with very simple ices, so I'm starting out with like water, H2O, what we drink every day, carbon dioxide, which is what we breathe out every day, just very, very simple molecules. And it's quite amazing to just start with these very, very simple components. And you just put a little bit of well, this is not a little bit, but you irradiate them. And you form amines. You form amino acids. You form really big molecules that it's just even difficult to detect with our own technology. You form polymers. Yeah, you form a lot of very interesting components.

LP: Describe this chamber to us because it seems crazy almost that you can recreate these space-like conditions here on Earth in, essentially, a room. How strong is this chamber? What is it like? What's it built what is it made out of?

DQ: Yeah, so this it's an all metal vacuum chamber, so it's shiny. [LAUGHS] It can be shiny. Yeah, it's a metal chamber, and you put together ConFlat flanges. I'm basically I don't know. I guess I feel sometimes like I'm a plumber in the lab. I'm just building things and putting components together.

LP: Did you build this chamber?

DQ: I did not build this particular chamber. This chamber was built way back before I was born, I believe. But I have built chambers, and I'm building one right now at SwRI with a team of engineers. And so the chamber itself is we want to get rid of all the stuff that's in air so we pump it down. So we use a turbo molecular pump, and this turbo molecular pump is essentially, the blades are so fine that it literally kicks out molecules and atoms out of the vacuum chamber. And so you have a very, very, very low pressure, and in that case, you're able to just really study the ice chemistry and not the ice chemistry with all these air contaminants.

LP: So the purpose is you're showing what might be happening in space how, these building blocks of life form in asteroids. So the chamber and the conditions in the chamber represent the interstellar cloud.

DQ: So we form an interstellar ice in the vacuum chamber at the temperatures of an interstellar cloud, and we irradiate the interstellar ice analog in the vacuum chamber. And then when we're done, we pull out this it goes from an ice to a residue, that whole thing is simulating what would happen in an interstellar cloud.

But for the asteroid part, the asteroid is actually really hot. The asteroid is actually it has liquid. The ices essentially melts on the asteroid, and so you actually have liquid, aqueous chemistry, on these asteroids. And so what we did was we took our interstellar residue, gunky residue, and then we immersed it into or we put it into a liquid in water. And that's how we simulated asteroid conditions.

LP: Oh, OK. So the thought is maybe that this residue forms before it ever touches the asteroid, but then once it--

DQ: Exactly.

LP: So it's already formed when it intermingles with the asteroid and the liquids in the asteroid. And then it becomes submerged in the asteroid water, and then that's how it gets encapsulated in there.

DQ: Yep, that's how we don't have direct proof of it, but that's the evidence. The evidence is leading to that, and that's what we're trying to explore and simulate.

LP: OK. All right, so really amazing stuff you're doing in a lab, creating this residue that holds the building blocks of life, and you described it a little bit to us. But if you could, tell us more about this organic residue. I've heard it called the goo of life. Can we call it that? What does it look like? What does it feel like?

DQ: Yes, that's I also call it this gunky goo stuff of life. I did not touch it, but I was nervous. I didn't really want to touch it. But I looked at it, and it's really beautiful. It really makes you feel closer to this type of research, and I think it goes back to the question of, why do we care to understand the origins of these amino acids, these building blocks of life, in deep space?

And when you just look at it, this gunky residue that you formed, and it's like, wow, I just simulated something that this may exist out in deep space, and it looks like the gunk that may be participating in the origin of life here on Earth. So it definitely made me feel like a believer more and that there is really there could be a very strong connection to what's out in deep space and what we have here on Earth.

LP: So that's amazing. So it's a beautiful, gunky residue. [LAUGHS]

DQ: Yes, it's very beautiful.

LP: So we do have a picture of it, so I'll make sure that ends up on our Episode 52 web page for our listeners to see it. But the picture we have, it's in this little tube, or it's in this little-- it's in this little container, and it's just a slight amount. So how much or what does it take to make that little amount? Or how can you make more of it?

DQ: It takes me maybe half a day to make the residue to which you can really look at it. I think that picture particularly had a lot, so if I was super enthusiastic and wanted to stay in the lab for days and days, I could probably make a lot of residue. But I have a life, so. [LAUGHS]

LP: If you had the time of an interstellar cloud, you might have more time.

DQ: Exactly.

LP: All of eternity, you might have more time to make more.

DQ: Yeah.

LP: OK, so I have a weird question next, but I have to ask because we're talking about having this goo in the lab that's essentially has the building blocks of life there. So if left in the right conditions, do you think that this residue could develop further, I don't know, spark a simple life form? Sorry if this is a weird question.

DQ: I love this question. It's very it makes me get creative, which and a different type of creativity that I don't get the opportunity to do so. I would love to explore that, and it's a question that a lot of-- that a certain group of colleagues are exploring that, trying to we are that is really like the golden question, the million dollar, billion dollar question is, what is the link between these gunky residues and actual life?

And I would say that's what we're trying to do when we're pairing when I did this experiment, where I was simulating interstellar conditions and asteroid conditions, that's us making the link between the interstellar cloud to the asteroid. And now we should have more collaborations between like someone myself as an astrochemist, and I would love to collaborate with maybe a biochemist or someone who understands more of, what does it take to actually kick start life?

I just have some of these basic ingredients, but I need to work with a chef. So yeah, I would if anyone's out there listening, I would love to…

LP: Explore further. So is there an ethical component to this? Is there a place where maybe you wouldn't go past? Or do you have any-- does anything give you pause to want to take this further as far as the ethical side of things?

DQ: Yeah, like being another Dr. Frankenstein.

LP: [LAUGHS]

DQ: Yeah, that's what I think of. Yeah, it's also a topic I feel nervous sometimes to talk about, too, because everyone has a different perspective on this situation of ethics. I'm just super excited and curious. I am that nerdy curious scientist that just wants to push the limits, and that's where my brain is.

And I just I'm not thinking that far because I almost feel like it's never going to happen. I'm never going to make that connection to actual to going from prebiotic to actual biology all in one go. I think I'm more excited of the idea if that were to happen.

LP: Do you get any pushback with the work you're doing?

DQ: I do feel supported, but I do get pushback. I have had articles. I've had emails, where people are not happy that I'm studying this kind of research. Yeah, not everybody's happy, but…

LP: Yeah.

DQ: I appreciate the support that I get.

LP: So let's talk about the first time that you whipped up this organic residue. What was that like? Did you know what you were going to get? Were you surprised?

DQ: Yes, so I wasn't super surprised because people, they've done this before me. Making these residues have been done in the past. The only well, not the only, but a big difference that I had done was I then taken these residues and processed them under asteroid conditions, and that was the unique aspect of this, was taking it from the interstellar cloud to the asteroid.

But going back to looking at this stuff, yeah, I guess I wasn't too surprised on paper. But it's just so like I said, it's beautiful to look at. Looking at it, it gives you a whole different experience. It made me feel much more close to the idea of connecting interstellar-space conditions to actually constructing life here on Earth and elsewhere. So yeah, on paper, it wasn't surprising, but in reality, it felt a bit emotional.

LP: Yeah, it's got to be, probably something that you were looking forward to, and then it came to fruition. So that had to have been a big moment for you. So in addition to creating this residue in the lab, this material that encapsulates the building blocks of life, you are part of an international team that has used the James Webb Space Telescope to study ices that exist in the darkest regions of the interstellar clouds. So why is this significant?

DQ: Yes, so this was a very exciting project. I feel so grateful that I had people who thought of me and thought that I would be a good addition for this James Webb Space Telescope project. So you know who you are, and I'm thinking you on this podcast. The reason that it what makes this particular observation so unique, looking into this dark side of chemistry in these interstellar clouds, is before the James Webb, we could look at these interstellar clouds. And we saw these ices before.

But you needed a very highly sensitive telescope to look deep, way deep, into the cloud. You can think of it as like, if you have this dust cloud that is just it gets thicker and thicker the deeper you go, and so with like if you have a flashlight, you can't see the deepest regions. And the deepest regions are really cool because it's very cold. And there's a lot of ice, and there's a lot of chemical complexity.

But we weren't able to see that before because we just didn't have a telescope that could detect the light that would be coming out from these clouds. And now we do. We have the James Webb. And now we're able to basically look at this whole, new treasure chest of ices, this new inventory of ices that we haven't been able to probe before. And so we have a more complete understanding of the chemical complexities in these interstellar clouds.

LP: And how does that work link back to the other project we've been talking about? You mentioned you're getting a better view of these interstellar ices. Why is that important to understanding the building blocks of life, again?

DQ: Yeah, so there's a number of things some of the things that we saw and some of the things that we didn't see. Those are both two very important things. So one of the things that we saw were not it wasn't full evidence, but we saw very strong case for more complex organics, like ethanol.

So ethanol is the type of alcohol that you would find in beer and wine, for example, so there's alcohol deep in these interstellar clouds. And that's getting closer to that's part of the building blocks of life. And so we're finding these bigger, complex organics in these clouds, indicating that, OK, maybe some of these complex organics have been passed down from the cloud to the asteroid and from the asteroid to planets.

And then there are things that we didn't see. So for example, there's a total amount of sulfur, so sulfur is an element that-- it doesn't smell great. It smells like rotten eggs, but it's important to life. It's considered a biogenic element.

And we only detected 1% of the sulfur that we were expecting. Still, even when we go deep into this cloud, we are still only detecting 1% of the sulfur that we are expecting, so 99% of the sulfur in these interstellar clouds is missing. We don't know where it is, where it's locked up, and so that is really interesting because then that's telling us, OK, we've now like explored all parts of this cloud. And it's not in the ice, so where is it?

LP: So essentially, you're bringing together all these different pieces of this puzzle, and you're trying to see what picture emerges, so really intriguing work. Again, you told us you're an astrochemist. We'd love to learn more about our scientists and our guests here on the podcast, so would you mind sharing a little bit about your background? How did you end up researching this particular area of space science?

DQ: Yeah, I love sharing my background because, every time I tell someone I'm a scientist, the first thing they say is, oh, you're really smart. It feels nice to hear, and I appreciate it. But I also, at the same time, I want to break that idea as well because I always so when I was younger, I really liked space and the cosmos, but school was really challenging for me.

And I didn't have that teacher that was like, oh, that teacher motivated me to be a scientist. No, I would actually get in trouble frequently, not frequently, but I got in trouble. And I didn't have the best grades, and I actually have a diagnosed language disorder. It's hard for me to sometimes follow directions and speech, and I'm much better at teaching myself.

So anyways, I never really considered myself as a smart kid. But I grew up, thinking, oh, well, if you want to be scientist, you have to be very smart because that's what everyone says. But I did have a mentor who was an astrochemist, and that was the first person that gave me that reality that, no, you don't the perspective of your teachers, and your peers, or your parents, your family, it doesn't matter.

If you have the motivation to do this, you can. So that is what basically made me feel confident to be a scientist. And I went to college and studied astronomy and chemistry, and then I went to graduate school. And I enrolled in a Ph.D. program, and I got kicked out. I got kicked out after one year in a Ph.D. program. I was told basically I wasn't qualified, and again, I just didn't listen. And I felt like I was smarter than that, and I felt very accomplished. And I felt that I could if I was just in the right hands with the right people that I could pursue this, and so I did. And I ended up doing really well somewhere else. I went out to the Netherlands. I got my Ph.D. I won a few dissertation awards from my time there, and then did my postdoc NASA Goddard, and got some beautiful articles out of there. And now, here I am at SwRI as a space scientist, so I love sharing that background because it's not what people think of as a scientist.

LP: Yeah, what a great story and I think a great example for students today. I love the lesson there that you shared don't let others define who you are. And it was your motivation, your perseverance, and, I think, your curiosity that kept you moving along.

So thank you so much for sharing that personal story. So where do you think this work will lead? What's next to unlock?

DQ: Yeah, there's so much to unlock, and this is a beautiful era to be in as a scientist because of all these different space missions that are heading out to Jupiter and soon to Uranus. Voyager's out already in interstellar space. There's going to be a lot of data coming in, and personally, I am just really I'm just so stuck in this sulfur issue with the James Webb Space Telescope, and where is all the sulfur in the interstellar cloud? I know it sounds so nerdy and so specific, but I just think sulfur is very important to life. And the fact that 99% of it is missing in the cloud and that has implications for, where is all that sulfur locked up in planets then? When this cloud becomes a solar system and a planet, and how does that sulfur chemistry happen? And so that's what I'm specifically going to investigate at SwRI is this sulfur issue, where did all the missing sulfur go? And I'll be studying that in the laboratory, and then that will help with understanding some of the data from the James Webb Space Telescope.

LP: Where is the sulfur? I feel like we need t-shirts and bumper stickers and make it a whole thing. [LAUGHS]

DQ: Yes.

LP: I have no doubt you're going to find it, Dr. Danna Qasim.

DQ: Thank you.

LP: Let us know when you do. We'll have to have an update. All right, well, truly such extraordinary research and world-changing work you are doing at SwRI. I am so curious to see where your work leads and what you uncover in the future, so thank you for sharing your knowledge and findings with us today, Danna.

DQ: Yes, thank you so much for having me. I really enjoyed this.

And thank you to our listeners for learning along with us today. You can hear all of our Technology Today episodes and see photos and complete transcripts at podcast.swri.org. Remember to share our podcast and subscribe on your favorite podcast platform.

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Ian McKinney and Bryan Ortiz are the podcast audio engineers and editors. I am producer and host, Lisa Peña.

Thanks for listening.

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Using spacecraft data, theoretical analysis, and sophisticated computer models, Institute scientists are investigating a variety of topics in space science, including terrestrial and planetary magnetospheres, planetary geology and atmospheres, the icy moons of Saturn and Jupiter, the origin and properties of the solar wind, the hydrology and radiation environment of Mars, and solar and planetary system formation. 

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