ASU students learn from the dead at Teotihuacan


November 22, 2017

Teotihuacan was once the largest and most influential city in the ancient new world. Yet its social structure seems to be more egalitarian than those in its fellow ancient cities.

“Most ancient societies had an elite class that lived in big houses and had big fancy tombs. Then you got the commoners living in little houses and their burials were very simple with no gravestones,” said Michael E. Smith, a professor in the School of Human Evolution and Social Change at Arizona State University. “You don’t seem to have that distinction at Teotihuacan.” Intern, Noah Livingston, looking at the Teo Mapping Project and pointing with a piece of obsidian Intern Noah Livingston looks at the Teo Mapping Project, pointing with a piece of obsidian. Download Full Image

Mesoamerican expert and archaeologist Smith is the director of the Teotihuacan Research Laboratory, an ASU-managed facility for on-site archaeological fieldwork to further understand ancient urban life. Smith is leading the lab’s new project, “Burials and Society at Teotihuacan.”

“At Teotihuacan, the standard residence was 10 times as big as an Aztec peasant house,” Smith said. “There’s something strange about the level of inequality being lower, and there seems to be a lot of prosperity. So maybe the burials will provide another perspective on this because we don’t have a good handle on how society was organized at Teotihuacan.”

A team of undergraduate students will be creating a database of the burials and offerings from the city, which has never been done before. They will analyze patterns of wealth, status and gender within the burials.

“I’ve always worked pretty heavily with undergrads,” Smith said. “I like working with undergrads because they’re just figuring out that they can do something beyond just learning knowledge from a book or from a class. I think the kinds of experiences and skills they’re getting are valuable in lots of ways.”

A picture of the Teotihuacan Mapping Project, a huge collection of maps of Teotihuacan and the structures

A picture of the Teotihuacan Mapping Project, a collection of maps of Teotihuacan and the structures

The students' potential discoveries can contribute to studies of our modern world, such as alternative governmental systems, how cities rise and fall, and the ways social practices change over time.

“No one has really looked at burials systematically, and we can learn a lot of things from the data of what was excavated,” Smith said. “It’s a source of information that hasn’t really been exploited.”

Emily Edmonds, an undergraduate student studying anthropology in the School of Human Evolution and Social Change, is one of the students working on the research project. She processes the documentation side of the project by reading the materials that have been written on the burials already and using them to help guide the group’s data analysis.

“The project is probably going to go in a couple of different directions as we figure what, exactly, we are looking for,” Edmonds said. “Just doing some of this data analysis, I’m noticing we should be looking for certain things, or we need to fix a variable within it, and I think it’ll be really exciting when we get our own data.”

Another undergraduate working on the documentation portion of the project is Noah Livingston. As an anthropology student, he is grateful for the skills he is learning within the lab because he knows will help him in his future career.

“I’ve already gained a lot from this project,” Livingston said. “I find our research and Teotihuacan itself tremendously fascinating. I also enjoy being able to apply what I’ve been learning in my classes to a real archeological project. I get to gain experience in working on long-term research, from design onward.”

The project will continue into the spring semester with the undergraduate students compiling a comprehensive catalog of residential burials and their associated offerings at Teotihuacan.

“It’s sort of an experiment,” Smith said. “A project that is, in large part, run by undergraduates. I think the experience of doing research is really helpful because you’re not just learning something and remembering something; you have to figure out how things work and how to evaluate things, and it just has lots of aspects of learning an experience.”

Rachel Bunning

Communications program coordinator, School of Historical, Philosophical and Religious Studies

The carbon catcher: Q&A with ASU's Klaus Lackner

ASU professor on what it will take to make air-capture technology take off


November 22, 2017

Klaus Lackner is concerned. And he thinks you should be, too.

The concern of the Arizona State University professor and founding director of the Center for Negative Carbon Emissions is simple: There’s too much carbon dioxide in the atmosphere. The proposed solutions, like capping carbon emissions, tend to focus on slowing the rate at which we pump out carbon dioxide. Lackner has another idea. Klaus Lackner in his lab with carbon-absorbing material ASU Professor Klaus Lackner, founding director of the Center for Negative Carbon Emissions, says there are technical hurdles with carbon air capture but that the bigger challenge is getting past people's objections that it can't be done. Download Full Image

He has developed technology that captures carbon dioxide from the air at rates much faster than trees and plants. What’s more, this technology could be mass produced and deployed worldwide.

On the heels of his ASU KEDtalk presentation, Lackner talked with Knowledge Enterprise Development writer Kelsey Wharton about the inspiration for his elegant technology, the challenges to advancing it on a large-scale and how everyone can help make it happen.

Question: Did you have a eureka moment in developing carbon air capture, or was it a slower evolution of ideas? 

Answer: Both. The eureka moment happened when I looked at devices that were passing air in order to run wind turbines. It struck me that if they instead scrubbed CO2, they would have a much larger impact on the carbon footprint than they had from making energy. Energy allows you to reduce the CO2 footprint because you displace fossil energy. Scrubbing it out allows you to remove CO2 that already came out, so you also reduce the footprint.

This made me ask the question, "How much CO2 is actually in the air compared to how much energy is in the air as wind energy?" And I found there's far more CO2.

I said, “This has got to work.” Because contacting the air is obviously easier than it is for a windmill. The windmill contacts the air in order to remove kinetic energy, and I need to contact the air to remove CO2. To have the same impact, I can be a hundred times smaller than a windmill. That was the “aha” moment.

I found out, though, when I look back, I wrote a paper five years earlier where we talked about the possibility of doing this, but we didn't go deeper into it then.

Q: Sometimes those things need to simmer.

A: Yes, there's a slow part with this, too. I clearly had thought about it before because we wrote a paper where we said, "If you really needed to, we could get the CO2 back out of the atmosphere." Then five years later I wrote a little conference paper where we said, "It's actually an option. We should think about it seriously." That's when I started.

Q: What challenges or failures have you experienced along the way to creating CO2 air-capture technology?

A: There are different kinds. There are the technical ones. There's also a bigger challenge that people said it’s just impossible: "You're wasting your time. This is not working. Forget it." People said it's thermodynamically not possible. No, it’s thermodynamically quite possible, and here's the paper that says so. Now they say, "It's just very difficult."

I sort of relate that [sentiment] to air flight. People were also very sure that it couldn’t be done. I have an analogy there, too, because you could look out of a window — you don't see any right now, but there are birds flying. They clearly are heavier than air and they clearly fly, so yes, it is possible. You look out of this room you see plenty of trees, so it's clearly possible to capture CO2 out of the air; you just have to do it the right way.

The other part, which is still a serious obstacle to this day, is that there are two groups I have to convince. One is the climate skeptics. "Why in the world would you want to solve a problem that doesn't exist?" They're at least consistent, even though it's nonsense that climate change doesn't exist.

Then there's also a strong environmental voice that basically says, "If you do that, then people won't change their lifestyle."

That actually makes it hard to get this type of work funded. It's hard to make this kind of work move forward. As a consequence, when we really need it, it's probably not ready yet. That's where the obstacles are.

Q: Some formidable ones.

A: Some formidable ones, but I think eventually that obstacle will fall by the wayside because physics has a nasty habit, nature has a nasty habit of asserting itself.

The biggest challenge actually is overcoming that which people call a "moral hazard." I think it's fundamentally wrong. We answered this in a Science letter, where I said, "Somebody is about to drown and you throw a life preserver and you're not going to argue that throwing a life preserver may prevent people from learning how to swim."

The other thing I say, we're in a car coming up at a sharp curve and we're going to hit the guard rail. There's no question in my mind that we will. Now the question is, will we roll over or will we just have a nasty scrape in the fender? To argue, "Don't touch the brake!" may not be the right way to think about the problem.

At this point we need to do everything we can. It's also worth keeping in mind, if we overshoot, there will be irreparable damage. I don't think we can avoid that anymore. At this point, the question is having to minimize the irreparable damage.

Take a look inside Klaus Lackner's ASU lab as he explains how his carbon air-capture technology works.

Q: If a person or a foundation came to you today and said, "We're ready to invest $100 million in this," what would you be able to do?

A: I would pull together a team to make this work, to make air capture work in multiple flavors and start creating negative emissions people would buy. I think, for that amount of money, you can do that. I think it would take two or three years to make one or two versions of the technology work, and you then would be at a starting gate to really pull this out.

With this kind of support, you can get the engineers and also the people who can put all the other things around it to turn it into something that works. I am confident that at that level, you could do it.

Q: For people who want to see this technology developed on a large scale but don't have $100 million lying around to invest, what can they do?

A: Ask for a button on the [gas] pump [to buy carbon offsets]. That will drive the technology. That would allow you to buy renewable energy. You should get to the point where you say, "I clean up the CO2 I produce. If I fly somewhere, I'll buy the offset."

By the way, I would make sure it's the real offset, and I would not count saying we improved the efficiency of a power plant, or a coal plant, and therefore we have created a carbon credit.

That's why I think once this becomes real, an important ingredient in the story — and that's the part where the $100 million would go — is to actually truly create a certification mechanism that says, "I can assure you that carbon has indeed been put away, and this is how it has been done." This is fair and square, and it's not a gimmick where we make it look like we've reduced CO2 emissions.

Q: Is there one particular challenge or barrier that is the standing in the way of this becoming a widespread technology?

A: Cost. That's a fundamental problem with new technologies. They always start expensive and then become cheap. In the high‑tech computer side, you get away with it because you have initial applications for which the high price is OK.

I'm thinking now of an old CD‑ROM. The first one I bought, I spent probably $20 on this little disk, but it was worth it because I suddenly could store 600 megabytes of data on a little thing I could leave in my drawer and come back a year later and it would still be there. This was powerful.

Eventually, they came down to $10, then 10 cents. But nobody could really predict that at the beginning, except once you start mass producing, you come running down this curve. But it is important that somebody at the beginning said, "I have no trouble spending $20."

I also think it has to come from the grass roots. I think we have to convince people to clean up after themselves. That's that waste-management story I talked about [in my ASU KEDtalk]. There’s no better way of manifesting that than by saying, "I'm doing it." 

Interview has been condensed and edited. The Center for Negative Carbon Emissions is part of the School of Sustainable Engineering and the Built Environment in the Ira A. Fulton Schools of Engineering.

Kelsey Wharton

Science Writer, Knowledge Enterprise Development