U of M researchers lead NASA’s first solar flare observation campaign

Understanding solar flares can help us react in real time to avoid power grid and communications disruptions

MINNEAPOLIS / ST. PAUL (04/18/2024) - For the first time, a team of University of Minnesota Twin Cities researchers launched a sounding rocket to study solar flares in real time. The rocket, named Focusing Optics X-ray Solar Imager (FOXSI-4), is equipped with an X-ray telescope that gathers precise measurements of this solar phenomenon.

A solar flare is a bright burst of light from the sun that can be seen across the entire electromagnetic spectrum. Solar flares and their accompanying plasma ejections can cause geomagnetic storms that can have impacts on power grids and communication satellites on Earth. Understanding how these solar flares happen can help us better react in real time to avoid disruptions.

In NASA’s first solar flare observation campaign, the researchers are studying the earliest signature of solar flares. A major challenge is that researchers only had five minutes to collect the data after the FOXSI-4 rocket was launched from the Poker Flat Research Range in Alaska. This kind of effort had never been tried before during a solar flare.

Physics and Astronomy Associate Professor Lindsay Glesener explains the importance of NASA’s first-ever solar flare observation campaign.

Sounding rockets typically launch from the White Sands Missile Range in New Mexico, but the solar flare campaign required a more flexible launch schedule than that missile range can allow. In Alaska, FOXSI-4 was ready on the launch pad for two weeks, waiting for the perfect opportunity to capture a solar flare.

Once the sounding rocket was launched, they looked at low energy X-rays from National Oceanic and Atmospheric Association (NOAA)’s GOES Satellite. They were able to study live solar flare data at the launch facility to pick the perfect moment to launch their sounding rocket. 

“Hard X-rays are closely linked to the energy release that powers solar flares. There are a lot of questions that go along with this,” said Lindsay Glesener, a University of Minnesota associate professor in the College of Science and Engineering’s School of Physics and Astronomy and lead on this project. “We know that the energy is stored in the magnetic field of the Sun’s corona prior to the event, but we don’t know how the event is kicked off or the details of what happens to the energy after it is released.” 

The energy release happens very early on in a solar flare, so researchers needed to observe the X-rays as close to the start of the solar flare as possible. The goal of this project is to collect meaningful data in that five-minute time period to expand this research to build solar dedicated spacecraft instruments that would observe the Sun for longer periods of time.

“We are conducting this research now because we are in a period of relatively high solar activity, the solar maximum, which means there are a large number of solar flares happening on the Sun,” Glesener said.

FOSXI research team standing in front of sounding rocket in Alaska.
Several University of Minnesota researchers were part of the international team of scientists who launched sounding rockets to study solar flares on the Poker Flat Research Range in Alaska. Credit: Lindsay Glesener

A successful launch of FOXSI-4 was completed on April 17, 2024. The team observed a M1.8 flare. According to NASA, solar flares are classified by their strength. The smallest ones are B-class, followed by C, M, and X, the largest. X-ray data was successfully collected, right after the peak of the solar flare. Watch a video of the sounding rocket launch on the Poker Flat Research Range in Alaska Facebook Page.

Image of sounding rocket launching in Alaska.
FOXSI-4 launched at 2:13 p.m. local Alaska time at the Poker Flat Research Range in Fairbanks, Alaska, on April 17, 2024. The rocket reached altitudes up to 168 miles and was able to successfully observe the solar flare. Credit: NASA/Lee Wingfield

FOXSI became the first solar-dedicated instrument to observe hard X-rays with focusing optics in 2012. The three previous successful FOXSI sounding rocket launches were aimed at studying the Sun when there was no activity happening. FOXSI-4 is equipped with new technology including high-resolution hard X-ray mirrors to better isolate the many regions of magnetic energy release during flares.

In addition to Glesener, the launch team included University of Minnesota ​​researcher Thanasi Pantazides, postdoctoral student Kris Cooper, and Ph.D. students Yixian Zhang and Marianne Peterson.

This project is a collaboration between the University of Minnesota, the Space Sciences Laboratory at University of California-Berkeley, NASA Goddard Space Flight Center, NASA Marshall Space Flight Center, University of Tokyo IPMU, Nagoya University, Fachhochschule Nordwestschweiz (FHNW), National Astronomical Observatory of Japan (NAOJ), the Japanese Aerospace Exploration Agency, and Johns Hopkins University Applied Physical Laboratory.

Read more about the project on the FOXSI Sounding Rocket research page.