University of Minnesota
School of Physics & Astronomy

Research Spotlight

Space Physicist to provide exciting research opportunities for students

Linday Glesener and Kendra Bergstedt
Lindsay Glesener (right) and student, Kendra Bergstedt
Richard Anderson

Lindsay Glesener is a faculty member in the School of Physics and Astronomy, studying high energy events in the Sun. Glesener uses x-rays to observe solar flares and coronal mass ejections. These events throw intense amounts of of plasma and radiation into space, causing the Earth’s aurorae and causing high radiation environments in Earth’s orbit, adversely affecting spacecraft. Glesener studies this topic from a fundamental physics perspective, trying to answer remaining questions about how these solar events are energized and the high-energy nature of the Sun.

For example, physicists don’t understand why the Sun’s outermost layer, the corona, is so much hotter than the surface of the Sun, how the particles that are ejected get accelerated in the first place or how energy transfer happens at such a high rate. It’s been theorized that the solar flares are triggered by release of energy from the sun’s magnetic fields, which occasionally become stressed and “reconnect” to a much lower energy level. This dumps huge amounts of energy into the corona, causing particles to move at relativistic speeds. There’s a great deal of energy transferred in this process, up to half the energy released in a solar flare, which is unusually high. There have been some proposed answers to this mystery, such as shock acceleration, turbulence, and contracting magnetic fields. Glesener is trying to help narrow down the search by using high-energy X-ray data from spacecraft that are dedicated for the Sun in orbit around the Earth, as well as spacecraft data at other wavelengths for context, and sometimes ground based telescope data as well. “We have a wealth of data, but there are still a lot of things we don’t understand very well. So we’ve decided we need even better data than what we already have.”

To get better data, Glesener is part of several analysis projects, as well as researching new instrumentation and new technologies. “The end goal of a lot of that instrument development is to try to get a new spacecraft, but you can’t just go to NASA and ask for $200 million. They’re going to ask you a lot of questions about what’s your concept, what proof do you have that everything will work so that we know that everything is tested and tried.” Intermediary testing steps include trying out technology in the lab, and using sounding rockets--relatively small rockets -- that fly a payload into space. Sounding rockets don’t go fast enough or high enough to go into orbit or to escape the Earth’s gravity. A sounding rocket boosts a payload up into space, where it stays for a short while before falling back to Earth, almost in the same spot from which it was launched. With a sounding rocket you get into space for a total observation time of six minutes. “It’s quite exciting and dramatic because you spend a few years building this, and then you fly it and you have six minutes to do your thing. So you really have to make sure everything works.” She says that physicists usually recover the payload in good condition from these test flights, which is another advantage. “You get to take it back to your lab and assess everything, make sure everything’s healthy, do some more calibrations.” Sounding rockets are not just useful for testing. Glesener, says real science can be done, even in six minutes.

Glesener is also involved with designing CubeSats, which are a type of spacecraft that are about the size of a shoebox and weigh only a few kilograms. She has NASA and Air Force funding for this project which is a collaboration between the School and The Department of Aerospace Engineering. These Cubesats will carry instrumentation to study high-energy solar flares. They are typically taken up to the Space Station with supply shipments and launched from the Station’s CubeSat launcher, or else taken as “piggyback” payloads on launches for larger spacecraft. She says that in the past these small craft were only used for student training or to test instrumentation, but scientists are now building and flying CubeSats that stay up a year or more and make useful scientific measurements. “For students this is a really great opportunity. At some point, before they graduate, they will be able to say, ‘I built this payload that went into space.’”