Experiencing the Great American Solar Eclipse

They came in droves to witness the moon blocking the sun.

On Aug. 21 at MIT's campus in Cambridge, Massachusetts; at the MIT Wallace Observatory; and in eastern Idaho, members of the MIT community, and the public at large, gathered to watch what was hailed by many as the Great American Solar Eclipse — a solar eclipse that could be seeen across North America.

The MIT Department of Earth, Atmospheric and Planetary Sciences (EAPS) hosted the main event on campus, at the Kresge Oval. Armed with solar glasses and viewing devices ranging from a pair of specially filtered telescopes to paper plates, colanders, and pinhole cameras, organizers enthusiastically greeted several thousand attendees who showed up to view the partial eclipse. Megan Jordan, EAPS academic administrator, said that the 300 pairs of solar glasses on hand were shared by attendees, whose presence far exceeded the expected turnout. The event, organized by senior lecturer Amanda Bosh and others in EAPS, was well staffed with volunteers, postdocs, and students, as well as individuals in the observe@MIT stargazing group.

In Westford, Massachusetts, the MIT Wallace Astrophysical Observatory and MIT Haystack Observatory co-hosted another lively eclipse party for nearly 200 people on the Wallace grounds — the largest public event ever at the observatory. Despite months of hype and excitement, the partial eclipse did not disappoint here, either. Families gathered on the lawn from as far away as Virgina to see what looked like a bite taken out of the sun. Cool temperatures and a dimmed sky during the height of the obscurement were clearly noticable, even though the moon covered just over 60 percent of the sun's surface. 

Several families built and transported carboard viewers larger than the children using them to safely watch the sun. MIT Wallace site manager Tim Brothers set up a telescope filtered for safe viewing, and the line of people waiting to look through it at the eclipse stretched through the grounds during the entire eclipse party. Brothers also set up a live feed from another telescope, this one equipped with an H-alpha filter that narrows the visible spectrum to view details in the sun's chromosphere layer, as well as a live data feed from the ionospheric radar experiment at MIT Haystack next door. 

Further afield, some 50 MIT alumni and family members traveled together with EAPS Professor Rick Binzel to Rexburg, Idaho, to experience the solar eclipse within the region of totality — a narrow band across the U.S. where the moon completely blocked out the sun. The location was chosen based on extensive research by Binzel to determine a spot most likely to have favorable weather and clear skies. The MIT group got up early to avoid expected traffic and spent the eclipse on Brigham Young University's Idaho campus. The group, carrying MIT flags and a variety of safe viewing devices, enjoyed the spectacle after hearing expert lectures from Binzel on the science of the eclipse.

Preparations are already underway for the next total solar eclipse across the United States in 2024, for which the path of totality will stretch from Texas to Maine.

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President Reif to Class of 2021: “We are very lucky to have you!”

MIT greeted the incoming Class of 2021 with its annual Convocation in front of Kresge Auditorium, treating them and their parents to personal stories of what it was like to first arrive at MIT, as told by President L. Rafael Reif and three highly accomplished faculty members.

Reif described his own fears when he arrived at this campus, having grown up in Venezuela, not knowing anyone in the area. He worried, among other things, about whether he was good enough to succeed here, whether his English was good enough, and what it would be like to experience snow for the first time. But those fears were quickly erased: “Very soon, MIT became my academic home,” he said, “and this community became my extended family. I hope that you will come to feel that way, too.”

Those initial fears vanished, he said, when “I found that what mattered at MIT was not where you come from or who you know, but what you contribute: good ideas, new perspectives, hard work, and creativity.” MIT, he said, “was the first place where I could stop feeling self-conscious, particularly about what interested me.”

Those initial worries were echoed by three faculty members who described their own experiences upon arriving here. Kristala Prather, the Arthur D. Little Professor of Chemical Engineering, who earned her bachelor’s degree at MIT, recalled thinking when she arrived on campus and heard of the amazing accomplishments of her fellow students, “how the heck did they let me in?” And, she added, she felt the same way 14 years later when she received her appointment to the MIT faculty.

To those in the incoming class who might feel the same way, she said, “I want to be sure you know, you are here on purpose. … You are ready to take on this place!”

“MIT is a unique crucible, where you will be faced with challenges you didn’t quite expect, at an important time of your life,” she said. “My advice here is quite simple: Embrace failure! If you haven’t already, you’ll soon realize that failures frequently, and I might say usually, allow you to learn far more than your successes.” Failure, she said, “lets you know that your knowledge lacked depth, or your understanding was incomplete, or maybe your expectations were a little unrealistic. Filling in those gaps adds to your knowledge base, and how you go about recovering from those failures will teach you lifelong lessons.”

Prather added that students should seek experiences outside their academic specialties. “You have to have balance, something that allows you to get away from the rigors of academics and enjoy life. … So my advice to you is to have fun, explore, try new things, go new places, meet new people, hang out with friends, just have fun … but not too much fun.”

Martin Culpepper, a professor of mechanical engineering and MIT’s “Maker Czar,” regaled the students with his own experiences of early failure and having fun, such as the time he took apart his dad’s carburetor and found that there were quite a few parts left over when he put it back together and it didn’t work, or when he flooded the basement of his home while trying to fix the washing machine. He learned important lessons from that, he said, such as “what an insurance deductible is, compared to my allowance.”

But these experiences, he explained, really did end up paving his path to MIT. And once he got here, “every day here as a student I got challenged, every day I got to see amazing things that people were doing in their research, and every day here as a student I got to work with my mind and my hands.”

Culpepper added that “over the course of the next few years, you’re going to have tough days.” He gave the example from his first semester, when a professor found out he couldn’t afford to go home for Thanksgiving, and invited him to spend it with his own family. He ended up having a wonderful experience there, having a great meal, driving bulldozers, and talking at length about differential equations. It was a day that could have been really sad for him, he said, but ended up being a fantastic experience.

Sara Seager, the Class of ’41 Professor, a professor of planetary science and of physics, and a leading expert on planets outside the solar system, talked about seeing the total solar eclipse a week ago. She described how that event related to the kind of research she has been carrying out for many years, to detect planets around other stars by observing the dimming of light when a planet passes in from of its star — a kind of miniature eclipse. Seager is a leader of the team that designed TESS, a new NASA mission that will soon observe many nearby stars to watch for such eclipses — called transits — in order to learn much more about the characteristics of those distant planets.

She described how she posed a challenge to a class in the Department of Aeronautics and Astronautics to develop a system to control the accurancy of pointing for tiny satellites called cubesats so that they could be steady enough to carry out such observations. The students rose to the challenge, and after some further development, this system was launched two weeks ago by NASA to the International Space Station, where it will soon be deployed into space. That whole experience, she said, “captured the MIT spirit: This bold idea that no matter how crazy, if it’s backed up by physics, it’s worth developing.” Where others might dismiss an idea as crazy, at MIT the attitude is “‘Yes, let’s give it a try,’” she said.

As Reif summarized to the incoming freshman class, “Every one of you has what it takes to succeed here. … And I hope you will join us in facing the challenge of building a better MIT, and building a better world. Humanity is facing no shortage of serious challenges: climate, energy, disease, poverty. And MIT is a magnificent human machine for inventing the future. But MIT invents the future thanks to its students.”

Reif concluded by thanking the incoming students for the choice they made: “We are very lucky to have you. All of you had other options, and I am delighted and grateful that you chose MIT. You will receive a great education here, and all of us together will make a better world.”

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Inspiring the next generation of engineers

The halls of MIT were abuzz with 30 children and teenagers eager to be civil and environmental engineers for a day.

All relatives, friends or neighbors of members of the Department of Civil and Environmental Engineering (CEE), the young additions to the community were on campus for the second annual CEE Kids Camp, a day filled with science, technology, engineering, and mathematics (STEM) activities that showcased research topics throughout the department.

“We started CEE Kids Camp last year to show friends and relatives of our community what it means to work in CEE and to inspire the next generation of STEM students,” said Markus Buehler, head of CEE and the McAfee Professor of Engineering. “All of the children were excited to attend the event and to share what they created throughout the day. The camp was a unique opportunity to sample the diverse research areas in CEE for young children to show them what it means to be a civil and environmental engineer.”

The one-day camp was held on Aug. 15, beginning with an orientation breakfast, where the group received schedules, camp shirts, bags, and CEE water bottles. The kids also learned about the environmental impact of disposable water bottles and the importance of using reusable ones — information that became trivia question material later in the day.

Led by volunteers from across the department, the camp consisted of seven stations featuring kid-friendly activities that exposed participants to a number of research areas, including fluid mechanics, concrete sustainability, earthquake-resistant structures, and bioinspired materials.

“All of the activities and presentations were created with kids of all ages in mind; you could tell that a lot of thought went into making sure that everything was at a level everyone could understand,” said Kathy Briana, the lead organizer of the camp and a CEE staff member. “It was a busy day hosting so many kids and teenagers, but it was a lot of fun.”  

The participants were broken into smaller groups and took turns rotating between stations, which were hosted by faculty members, lecturers, students, and department affiliates. The tasks had varying levels of difficulty, but volunteers were on hand to guide each child through the activities.

Assistant Professor Tal Cohen, who specializes in nonlinear solid mechanics and material instabilities, hosted a session that invited children to build their own structures using a magnetic modeling kit. Participants were challenged to figure out how to build a structurally-sound model, and then to build bridges connecting their structure to their neighbor’s creation.

“I was expecting them to be much more creative than adults are, and it was very obvious that they were thinking of all kinds of solutions that we probably wouldn’t have even attempted,” Cohen said. “Some of them managed to have buildings with moving objects, some of them built forts, and some managed to build the bridge.”

Admir Masic, the Esther and Harold E. Edgerton Career Development Professor, and graduate student Hyun Chae “Chad” Loh led a demonstration about bioinspired materials, explaining how learning about biological materials and their designs can be hugely beneficial for the creation of new, high-performance, and more sustainable building materials. During his hands-on presentation, Masic allowed the kids to touch corals, shells, giant squid sucker rings, and silk cocoons, and to use an optical microscope to explore the intricate details of various natural samples, including a deep sea sponge. There was stiff competition to use the microscope, but each member of the group later got to wear 3-D glasses to get another look at the materials’ structures on the nanoscale. They also asked Masic questions about his work.

Outside, Marie-Julie Dalbe, a postdoc in Professor Ruben Juanes’ group, and undergraduate exchange student Hannah Galbraith-Olive used bubbles to explain the basics of fluid mechanics. Dalbe and her peers study multiphase flow, which is essentially studying the interactions between bubbles of two different fluids like water and oil, so simplifying their research into soap bubbles was a natural activity for kids, she explained.

Using a homemade bubble solution of soap and glycerin, Dalbe and Galbraith-Olive helped the campers explore what bubbles are, why they pop, and how bubbles can bounce. The participants experimented with blowing bubbles using cut plastic pipettes, mixed and tested their own solutions, and used bubble makers made of wood and rope to run through DuPont Court and create giant bubbles in their wake.

“The idea was to show them how to strengthen bubbles, like how to make them bigger and last longer. My vision was to help the kids figure out why bubbles pop, but they always said: ‘Because we pop them,’ ” Dalbe said with a laugh. “The goal was to explain how bubbles pop naturally, and how we could change that with different solutions and conditions.”

During other sessions, the camp attendees had the opportunity to create their own souvenirs. Graduate student Linda Seymour, postdoc Diego López Barreiro, and computer-aided design operator Steve Rudolph helped the participants mix their own rapid-setting cement and design coasters in petri dishes to take home. While waiting for the cement to set, the participants engaged in one of three sub-activities: a laboratory scavenger hunt, activity questionnaires, or coloring sheets, selected based on the age of the group.

Seymour discussed the history of cement and her research into sustainable concrete mixtures. She also told the group about her recent research trip to Italy, and let the participants look at a piece of ancient Roman concrete.  

“It was a really great experience to share what we do and to get kids excited about engineering,” Seymour said. “I think it also really helped me as a researcher to think about how I’m presenting what I’m doing and being able to tailor my research to a diverse audience.”

The groups were also able to use the department’s advanced manufacturing equipment to create their own puzzles. The session, led by members the Laboratory for Atomistic and Molecular Mechanics (LAMM) including research scientists Zhao Qin and Francisco Martin-Martinez, graduate student Isabelle Su, and visiting scholar Flavia Libonati, invited the children to select images that would become the basis of a puzzle. The researchers then brought the students into the lab to see the laser cutter in action as it translated the images onto plastic and cut the material into puzzles for the participants to take home.  

As engineers for the day, the groups were also tasked with building, testing and improving a variety of tools and designs. Doug Shattuck, a LAMM research affiliate and teacher at nearby Concord Middle School, and Najia Lloyd, a student member of the MIT-Concord Middle School Research Team, set up four stations for the camp participants to show their creativity and to try to build functional and well-designed devices. Among the tasks were building a marshmallow catapult with tongue depressors; using a magnet, battery, and wire to make a spinning motor; using a spool and pencil to create a racing dragster; and making a flying paper vortex. Shattuck established his personal benchmarks before the camp began, but his records were quickly beaten, and the kids were challenged with beating the records again and again throughout the day.

Shattuck found that the marshmallow catapult was the most popular activity. “I think the kids who were interested could get their minds into it more; it was a little bit easier to understand, and they could make it as simple or complicated as they wanted,” he said. “On the other hand, everybody could do it. And if they really wanted to, they could eat the marshmallows — as long as they didn’t hit the floor.”

The camp participants also learned how structures respond to earthquakes, and the importance of creating and understanding properly-engineered structures. CEE lecturer Gordana Herning explained to the group how earthquakes occur, showed the students how earthquakes are recorded in online databases, and showed the extent of the damage that they cause around the world.

Next, Herning challenged the children to build their own structures using string, pipe cleaners, and K’Nex building sets, and to consider what needed to be included in the designs to make the structures more resilient. The final task was to test the structures against an earthquake simulation using a shake table. Some structures were able to withstand the movement, but others ended up warped by the simulated disaster. At the end of the session, Herning identified potential areas for improvement in each creation and showed how critical the right designs can be for durability.

CEE Kids Camp wrapped up with an ice cream sundae bar and plastic water bottle trivia, where attendees competed to answer questions about the use of disposable water bottles, showed off their creations, and indulged in sweet treats.  

“The kids were really impressive in all of the stations, and it was great to see them engaging with our researchers here at MIT throughout the day,” Buehler said. “Each year CEE Kids Camp improves, and it wouldn’t be possible without the help of our community members who volunteered time and energy towards making the event such a great success. We’re already looking forward to hosting the camp again next summer.”

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Strength of global stratospheric circulation measured for first time

When commercial airplanes break through the clouds to reach cruising altitude, they have typically arrived in the stratosphere, the second layer of Earth’s atmosphere. The air up there is dry and clear, and much calmer than the turbulent atmosphere we experience on the ground.

And yet, for all its seeming tranquility, the stratosphere can be a powerful conveyor belt, pulling air up from the Earth’s equatorial region and pushing it back down toward the poles in a continuously circulating pattern. The strength of this circulation can significantly impact the amount of water vapor, chemicals, and ozone transported around the planet.

Now scientists in MIT’s Department of Earth, Atmospheric and Planetary Sciences (EAPS) have for the first time determined the strength of the stratosphere’s circulation, based on observations of key chemicals traveling within this atmospheric layer.

In a paper published today in the journal Nature Geoscience, the team reports that the stratosphere pulls about 7 billion kilograms of air up through the tropics per second, worldwide, at an altitude of about 20 kilometers. The researchers estimate that the average parcel of air can spend about 1.5 years within this layer before circulating back down to lower layers of the atmosphere.

The new estimate can help scientists gauge where and for how long water vapor, ozone, and greenhouse gases remain within the stratosphere. Scientists can also use the team’s method to determine future changes in the stratosphere’s strength — essential information for tracking the recovery of the ozone hole and the progression of global warming.

The paper’s lead authors are Marianna Linz, a former PhD student in EAPS who is now a postdoc at the University of California at Los Angeles; and Alan Plumb, a professor emeritus in EAPS; along with researchers from New York University, Karlsruhe Institute of Technology, the National Center for Atmospheric Research, Cambridge University, and Caltech.

Chemical laps

The circulation of the stratosphere is known to scientists as the meridional overturning, referring to the pattern in which air is pulled up into the stratosphere near the equator and transported along the Earth’s meridians, or longitudinal lines, before being drawn back down at the poles. Scientists have attempted to measure the strength of this overturning circulation, concentrating mainly on the speed at which water vapor rises through the stratosphere near the equator.

“Others have looked at this region of the equator where they think most of the stuff is coming up, and they’ve tried to characterize this using water vapor,” Linz says. “But that’s just looking at this narrow region, and it’s difficult to infer what the rest of the circulation looks like.”

Linz, Plumb, and their colleagues took a more global approach, making use of atmospheric measurements of two atmospheric chemicals, sulfur hexafluoride and nitrous oxide, taken around the world by satellites, weather balloons, and aircraft. They considered these chemicals to be ideal candidates to track, as they have no “stratospheric sinks,” or methods by which the concentration of these gases would change once they reached the stratosphere.

“The thinking is that what goes up must come down,” Linz says.

The scientists compiled measurements of both chemicals between 2007 and 2011, with the idea of estimating how long these chemicals took to enter, then exit, the stratosphere. They culled through the measurements, noting each chemical’s concentrations in given parcels of air throughout the stratosphere

at various locations and altitudes.

In particular, they looked over time to identify parcels of air rising up in the tropics, and later, parcels of air with the same concentration of chemicals, being drawn back down at the poles.

They reasoned that the time lag between the rising and sinking would indicate the time that parcel spent in the stratosphere. A simple calculation, factoring in the total mass of air in the stratosphere, would yield the speed at which that parcel traveled through the stratosphere, which essentially reflects the strength of circulation.

“If you think of a racetrack, and someone doing a lap on that track, you can measure the time they entered the track, and the time they came out of it, and you can calculate their average speed around the track if you know the track distance,” Plumb explains. “So this is like that, in a way.”

The air up there

The team performed these calculations and averaged the results for various altitudes throughout the stratosphere. Their calculations for both chemicals agreed almost perfectly at lower altitudes of around 20 kilometers, yielding a circulation strength of about 7 billion kilograms per second — comparable in magnitude to the strength of the overturning circulation in the ocean. 

“The most important thing to know in terms of impacts on climate change and ozone is what this circulation strength is like at this lower altitude, because that’s what is supplying chemicals to the stratosphere,” Plumb says.

Linz and Plumb compared their estimate with predictions of stratospheric circulation made by several climate models, and found that their estimate agreed with some models but not others. Linz says the team’s new estimate, and the method to calculate the stratosphere’s strength, can help to improve model predictions of warming and ozone development.

“If climate models are getting their stratospheric circulation wrong, they’re probably getting their ozone distributions wrong, which will have definite impacts on what the [predicted] trends are for global warming,” Linz says. “So having this benchmark is really valuable.”

The researchers are working to obtain more measurements, higher in the stratosphere, to better characterize the stratosphere’s strength at higher altitudes as well as within lower layers.

“We have this data and can say what the strength is at this level, but because we don’t have the data higher up, we can’t say nearly as much. So we really do need better observations in the upper stratosphere,” Linz says.

This research was supported, in part, by the National Science Foundation.

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Danielle Wood joins Media Lab faculty

Danielle Wood ’05, SM ’08, PhD ’12 is the Media Lab’s newest assistant professor in the Program in Media Arts and Sciences. She will officially start working at the lab on Jan. 16, 2018, to establish a new research group, called Space Enabled. Her mission is to advance justice and development in Earth's complex systems using designs enabled by space.

“Let’s keep striving for the ideal that space really is for the benefit of all humankind,” Wood said at a Media Lab event in March when she took part in a panel discussion about the future of space research. A scholar of societal development with a background that includes satellite design, systems engineering, and technology policy for the U.S. and emerging nations, Wood added that “space research is just a link in a bigger chain, part of a broad system of technology and art and science and design.” Her passion, she said, has been in designing satellite systems that serve societal needs while integrating new technology.

Growing up in Orlando, where she frequently witnessed space shuttle launches, Wood was inspired by how NASA teams came together to achieve such precise and challenging missions. But she also wanted to find opportunities to serve people directly in her career. Ultimately, that combination of interests led her to study aerospace engineering, policy, and international development. As a doctoral student at MIT, Wood traveled to 15 countries over 10 months as part of in-depth research on new satellite programs in Africa and Asia. The study explained how governments can harness international collaboration to foster domestic capability building and national development.

“Danielle ties space, development, and earth sciences together in a unique and impactful, Media Lab-like way,” says Media Lab Director Joi Ito. He adds that she “fits perfectly into our community like the puzzle piece you’ve been looking for forever.”

Research priorities and plans

In setting up the new group, Space Enabled, Wood plans to reduce barriers to applying space technology for societal benefit. Her research pursues a four-fold cycle that includes observation, explanation, co-design, and evaluation of complex systems that deliver public sector services, using methods from engineering and social science. “I am particularly interested in areas such as environment, health care, education, and law enforcement,” Wood explains. “These public service systems foster justice and societal development when they provide equitable access and high-quality service to consumers across the socioeconomic spectrum.” To that end, her group will partner with communities in the U.S. and abroad on long-term projects to implement new designs enabled by capabilities from space, such as satellite-based earth observation.

Wood’s group will include researchers and staff who bring together “multiple, seemingly unrelated interests. Some of the skill sets relevant to the projects I plan to pursue include engineering, design, technology policy, law, social science, geography, earth science, public health, history, art, and data analytics.” The Space Enabled team will not work in isolation: Wood says she expects to collaborate with other research groups at the Media Lab and also contribute to its Space Exploration initiative.   

Currently, Wood serves as the applied sciences manager at NASA’s Goddard Space Flight Center, where she focuses on using earth science findings for societal applications, such as food security and water resource management. Previously, she served as special assistant and advisor to NASA’s deputy administrator, and prior to NASA, she worked at the Aerospace Corporation, Johns Hopkins University, and the United Nations Office of Outer Space Affairs.

MIT roots and inspiration

At MIT, Wood earned a PhD in systems engineering, a master's in aerospace engineering, a master's in technology policy, and a bachelor's in aerospace engineering. At the Media Lab’s “Beyond the Cradle” event in March, Wood said that during her time at the Institute she was inspired by the expansion of space activity around the world and the potential uses of data captured by satellites. “But the question then becomes, how does the average person take advantage of that information? I look forward to co-designing solutions with communities to empower them to use space to make their own lives better. This is important in areas like food security, disaster response, and monitoring the spread of diseases influenced by environmental factors.”

During her time at MIT, Wood was awarded five fellowships, not only from MIT but also from the National Science Foundation, the National Defense Science and Engineering Graduate program, and NASA’s Harriett G. Jenkins Predoctoral Fellowship Program.

Wood’s work has drawn widespread recognition. She has won grants from the Future Space Leaders Foundation (2016) and the National Science Foundation (2013), and she’s received awards from many organizations, including the Global Competitiveness Conference (2015), the International Astronautical Federation (2012) and NASA (2010). Wood has presented her research through many scholarly publications, conferences, and invited talks across Africa, Asia, Europe, Australia, and North America.

Wood says she’s excited to return to MIT with a new perspective shaped by her professional path thus far. “I have worked in government, academia, and the private sector, which gives me an understanding of how each community functions. This experience will help me build strong teams in my future research at the Media Lab.”

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Bradley Olsen: Designing polymers with novel features

Tiny sensors made of antibodies, protein nanospheres that can clean up toxic spills, and gels that could be injected into a wound to initiate healing are just a few of the innovations emerging from Bradley Olsen’s lab at MIT.

Olsen’s research is based on exploring the physical properties of new types of polymers, and taking advantage of those properties to design novel materials that could have many useful applications.

“My group is really interested in two things: designing materials to address important challenges, and understanding the fundamental science that’s necessary for materials design,” says Olsen, an associate professor who recently earned tenure in MIT’s Department of Chemical Engineering.

His lab, which includes 15 to 20 students and postdocs, pursues these approaches mainly in the field of protein-polymer chemistry, a relatively new discipline that involves incorporating proteins into polymer materials. He credits those students with many of the key discoveries that have yielded these novel materials.

“It’s a group effort,” he says. “I think the talent and wisdom of the team far exceeds anything I could do individually.”

Block by block

Growing up in Minneapolis, Olsen became interested in chemistry in high school and applied to MIT in part because he was drawn to the Undergraduate Research Opportunities Program (UROP), which allows undergraduates to conduct research in the labs of MIT faculty.

While majoring in chemical engineering, Olsen spent three years working in the lab of Karen Gleason, the Alexander and I. Michael Kasser Professor of Chemical Engineering. At the time, Gleason was developing early versions of a technique known as initiated chemical vapor deposition, which allows scientists to use gases to form thin polymer coatings on a surface.

As a graduate student at the University of California at Berkeley, Olsen began working on synthesizing a special kind of polymers known as block copolymers. These materials consist of alternating blocks of two different kinds of monomers, which are the building blocks for synthetic polymers such as plastics and rubber.

When these monomers are arranged in blocks, it gives the overall material special properties. For example, the material may contain two monomers that would normally separate into layers, the way oil and water do. If those two chemically dissimilar molecules are bound together in a block copolymer, they can’t form separate layers. Instead, block copolymers assemble themselves into special structures, such as spheres, cylinders, or sheets, that help to minimize the interactions between the two chemically different blocks. Such materials are now commonly used in many products, including elastomers, adhesives, and personal care products.

As a graduate student, Olsen studied how these kinds of polymers could be used to control the nanostructure of semiconducting polymers. Then, as a postdoc at Caltech, he worked on developing injectable hydrogels, which could potentially be used for wound healing and stopping blood flow.

While at Caltech, Olsen received an offer to return to MIT as a faculty member, which he found hard to resist. “MIT certainly has very good students and very good colleagues, and I definitely had some nostalgia for the Boston area,” he says. “It’s fun to be back here.”

Useful materials

At MIT, Olsen has continued to develop block copolymers for a wide range of applications. In one area of research, he is designing materials where one block is a polymer and the other is a protein such as an enzyme or an antibody. These materials could then be formed into extremely sensitive biosensors.

“With this high-density array of proteins, you can potentially increase sensitivity by maybe a factor of 100 or 1,000, or even more,” Olsen says.

Protein-polymer hybrids also could be useful new materials that mimic the properties of nylons or polyurethanes, which are petroleum-derived materials that are found in hard plastics, coatings, insulation, and many other products. These new hybrids could potentially be produced in “biorefineries,” using sustainable sources of renewable biomass and making a positive impact on the environment. 

Another potential application for block copolymers is detoxification, using spherical “nanoreactors” whose surfaces are coated with enzymes that could break down toxic chemicals from an oil spill. Olsen has also continued working on hydrogels, including the development of wound-healing materials, in collaboration with MIT’s Institute for Soldier Nanotechnologies. 

“The things we work on are selected because the type of polymer-protein chemistry has a potential competitive advantage, and we try to apply our designs in that area,” he says.

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Political science debuts on MITx

When he arrived from Princeton University three years ago, political science MIT Professor Evan Lieberman was determined to find new and engaging ways of presenting course content. “I wanted to understand the students here, figure out what materials would interest them, and make a teaching impact,” he says.

One result of his efforts was 17.571 (Engineering Democratic Development in Africa). Offered for the first time in spring 2017, the class gives students the chance to apply engineering thinking to challenges in the practice of democracy in different African nations.

But now Lieberman, the Total Chair on Contemporary Africa, is taking instructional innovation to an entirely new level — and to new audiences. His new course, Democracy and Development: Perspectives from Africa, is the first MIT Political Science class produced exclusively for edX, the multi-university online education platform.

“I’d always been interested in technology, and wondered if there was a way to use the opportunity of a MOOC [massive open online course] to share ideas and to generate broad discussion on the issues important to my research,” Lieberman says.  So in 2015, he eagerly responded to a call for proposals from MITx, the Institute's online learning division, which works with the larger edX program.

His seven-week course, which launches Sept. 26, will introduce students from around the world to the drivers of democratic development in contemporary Africa. Lieberman has tailored his approach to online learners who might lack knowledge of Africa and its political institutions, but who are nevertheless curious about the promise and problems of democratic politics in Africa and elsewhere.

In developing the course, Lieberman says his first thought “was to make sure that lots of African voices get incorporated.”

“I can’t hide the fact that I’m a white American teaching about Africa — hopefully a sensitive one — and I felt it was important that students hear directly from Africans themselves,” he says.

Guided by a syllabus tackling topics such as the legacy of slavery and colonial rule, accountability and service delivery, human rights and the judiciary, and digital tools of democracy, Lieberman set out to interview a range of key players in African nations where democratic political institutions have taken root in the past few decades.

With funding from both MITx and the Center for International Studies, he recorded conversations with more than 50 African academics, politicians, leaders and students, who highlight key ideas and frame case studies intended to spur online discussion.

For instance, one module (the term for an online class) showcases a panel interview with three attorneys from a leading South African law firm. They discuss the legal recourse available to ordinary citizens who are legally entitled to but denied such public goods as land, housing, and education.

“We look at the ways law firms and other public actors use courts to challenge the government when government fails to deliver on constitutionally-mandated rights,” says Lieberman.
 
Each module consists of short video segments, ranging from four to 18 minutes long, which include interview clips and portions of Lieberman’s lectures where he distills key points from the interviews and frames larger questions intended to prompt lively online discussions.

“I’m excited to see what people have to say, whether they think the arguments they hear are plausible,” he says. “I will encourage students to provide examples from their own nations, when they can, and think about how politics can be helpful in leading to positive outcomes for people.”

In addition to these discussions, Lieberman is incorporating quizzes and short writing assignments to ensure that his online audience is digesting not just the video clips, but also the reading assignments. He hopes that such rich content will appeal to learners no matter where they live.

“There are universal concerns about how people come together to make decisions such that everyone feels they are more or less respected and that that the rules of the game are fair,” he says. “The course is about Africa, where there are specific challenges to democratic government, but the questions and ideas that arise are relevant in any political context.”

Given the frequent caricatures of “African strongmen and obedient followers,” he notes that Americans in particular “will be amazed by how thoughtful and sophisticated are the wide range of political actors in Africa, who are innovating in democratic government.”

After nearly 18 months of storyboarding, production, and editing — “the equivalent of preparing for three courses,” he says — it will soon be launch time. At last count, over 700 students from more than 100 countries had enrolled.

Lieberman says he has every hope that this “huge undertaking” will live up to his expectations and become, for a community of online learners, “an immersive experience where they can explore materials in a self-paced way, think hard about important questions, and pursue them after the course is over.”

de MIT News http://ift.tt/2wuGLqC