Shan Jiang, associate professor of mechanical engineering at the University of Mississippi, teaches students in his Summer Undergraduate Research Group. Jiang is one of three professors chosen this year for the National Science Foundation EPSCoR Research fellowship, in which he will help NASA develop 3D printing materials for construction on the moon. Photo by Kevin Bain/Ole Miss Digital Imaging Services
Research to span space construction materials, statistics to predict the future, stellar extreme physics
By Clara Turnage
For the first time, three University of Mississippi researchers have been awarded National Science Foundation EPSCoR Research fellowships in the same year.
Shan Jiang, associate professor of mechanical engineering; Nicholas McDonald, assistant professor of physics; and Hailin Sang, professor of mathematics, were awarded the Established Program to Stimulate Competitive Research RII fellowships.
“These fellowships can create career-spanning collaborations between experts that foster innovative science,” said John Higginbotham, UM vice chancellor for research and economic development. “The awards demonstrate the promise NSF sees in the future careers of these outstanding researchers.”
These grants fund extended visits by the fellows to jump-start research collaborations at some of the nation’s premier research facilities. Fellows also have the opportunity to bring a student along for the development experience.
The university’s awardees will use their grants to study some of the most extreme physics in the universe, advance 3D printing construction materials for the moon and Mars, and create spatial statistical models that can predict the future.
3D Printing on the Moon
Through complex computer simulations, Jiang will work with researchers at the NASA Marshall Space Flight Center to use surface matter found on the moon and Mars and simulants of that matter to create 3D-printable construction materials.
NASA – among many other space agencies and private businesses – wants to develop a base on the moon, but hauling construction machinery and materials from Earth is not feasible, Jiang said.
Instead, he and other researchers are working on ways to use soil found on the moon’s surface to create landing pads, blast shields and habitats for astronauts via large-scale 3D printing technology.
Jiang’s job will be to use simulations and complex machine learning algorithms to predict the mechanical behavior of these materials and determine which combination of binders and surface materials – known as regolith – will withstand extreme space climates.
“The temperature swings on the moon or on Mars are really, really large,” Jiang said. “We don’t know how these construction materials will react in such extreme environments.
“So, what I can do is use my computer model to predict different scenarios and give them the optimal procedure.”
Construction on the moon must withstand temperatures of up to 250 degrees during the day and as low as -208 at night, but also must hold up against intense pressure and heat from rocket launching and landing. A blast shield – the wall around a launch or landing pad – is built to block bullet-like projectiles a spaceship can kick up.
“For all of these structures, 3D printing is more convenient and it can directly use the material synthesized and processed on the moon surface,” he said. “The technology can actually help us print more complex structures than the traditional manufacturing method.
“Once we have the formula, I can do the modeling and testing of the materials to find a solution.”
Statistics of the Future
Sang will partner with researchers at Michigan State University to study long memory linear random fields, which is a mathematical model that can help researchers understand patterns in data such as weather changes or stock prices. Each of the data sets includes some random factors with dependent structure, which has historically made them difficult to estimate and predict.
By studying these complex models, Sang hopes to develop better, more accurate estimations and predictions that account for the random factors and the dependent structure.
“For example, you may consider the chance of high or low temperature, right?” Sang said. “You want to study it so you can make a prediction for the future.”
While any city may have a high or low temperature for a day of the year, numerous factors, including hurricanes, cold fronts and warm fronts, can throw off predictions. Accounting for the random factor can help researchers make better predictions with more accuracy, he said.
This type of statistical model could help businesses predict when sales for different items would be highest, which can help optimize which items are stocked when. The model can be applied broadly to environmental studies—such as predicting air pollution dispersion across cities—financial markets and even public health.
Sang and his students plan to develop four research papers for publication throughout the two-year grant, giving Ole Miss students opportunities to create tangible work in mathematics.
“It’s an opportunity for students to have a big vision in this field and pursue it,” Sang said. “We plan to not only work on our project, but to attend activities in their department, seminars, talks, and even workshops. It’s going to be a benefit for them, and for me, too.”
Bright Lights, Extreme Physics
One of the brightest and most persistent sources of light in the universe will be the subject of study for MacDonald and his graduate student. Blazars are streams of high-energy particles and radiation that shoot out of super-massive black holes, and they create light beams that are observable from Earth.
Blazars are unpredictable objects. Some are active for minutes, months, or years. But they also present a unique opportunity to study black hole behavior and high-energy physics.
“We are dealing with—without exaggeration—some of the most extreme physics in the universe,” MacDonald said. “A blazar presents us with an opportunity to look down the throat of a black hole engine, and that’s quite literally what we’re doing.”
Physics behaves differently near black holes and around blazars. Particles and time itself get wrapped up in a gravitational maelstrom. It’s in this realm of extreme physics that scientific discoveries are waiting, MacDonald said.
“The reason blazar research matters is because we are working the very limit of physics, and so I think studying phenomena that occur at this limit gives us the potential to learn more about nature on a fundamental level,” he said.
“If we’re going to learn something new about how physics works, I have a deep suspicion that it will come from observing extreme environments in the universe. And that’s certainly the case inside a blazar jet, which is like a cosmic particle accelerator.”
MacDonald and astronomy graduate student Kaitlyn Thurmond, of Kiln, will collaborate with the Boston University Blazar Group and will conduct blazar observations using the Perkins Observatory in Flagstaff, Arizona.
“For me, this is what it’s all about,” he said. “Getting students to the telescope and offering them a hands-on opportunity to help take actual observations. That’s a big part of what we’re trying to do: connect students from Mississippi to this whole scientific world that’s out there waiting for them.”
This material is based on work supported by the National Science Foundation grant nos. 2428880, 2429027 and 2429473.
