image: The SwRI-led team processed data from telescopes on WB-57 jets during the Chasing the Eclipse Project 1 in 2017 to help reveal key details about infrared emissions from the Sun’s corona. These wavelengths have only rarely been measured previously and may help us understand how the solar atmosphere reaches temperatures hundreds of times hotter than the solar surface.
Credit: Southwest Research Institute/NASA/Daniel B. Seaton
SAN ANTONIO — March 27, 2024 —Southwest Research Institute is leading two groundbreaking experiments — on the ground and in the air — to collect astronomical data from the total solar eclipse that will shadow a large swath of the United States on April 8, 2024. SwRI’s Dr. Amir Caspi leads the Citizen Continental-America Telescopic Eclipse (CATE) 2024 experiment, a broad scientific outreach initiative funded by the National Science Foundation (NSF) and NASA, that will engage community participants to make a continuous 60-minute high-resolution movie during the April 8 solar eclipse. Caspi also leads an investigation that will use NASA’s WB-57F research aircraft to chase the eclipse shadow.
“Total solar eclipses are unique opportunities for scientists to study the hot atmosphere above the Sun’s visible surface,” said Caspi, principal investigator of both projects. “The faint light from the corona is usually overpowered by the intense brightness of the Sun itself. Total solar eclipses allow scientists to view the complex and dynamic outer atmosphere in ways that aren’t possible or practical by any other means, opening new windows into our understanding of the solar corona.”
CATE 2024 will use a network of 35 teams of community participants, or “citizen scientists,” representing local communities along the eclipse path, deploying a “bucket brigade” of small telescopes — from the Texas-Mexico border to Maine — following the eclipse’s shadow path. This next-generation project builds on the experience of the first Citizen CATE experiment in 2017, led by Matt Penn of the National Solar Observatory, which used 68 stations to observe the August 2017 total solar eclipse that crossed the continental United States. CATE 2024 expands the scientific objectives by measuring polarized light and engages with new teams across this year’s eclipse path.
Additionally, for the second time, Caspi leads a project to observe an eclipse with NASA’s WB-57F research aircraft. In 2017, he led the first solar observations using these aircraft, outfitted with telescopes mounted in the aircraft nose cone. In 2024, Caspi’s team will deploy a new suite of sensitive, high-speed, visible-light and infrared imagers, built by NASA’s Langley Research Center, to observe the corona during the eclipse at 50,000 feet. These high-altitude observations both provide measurements that can’t be made from the ground and avoid any weather-related risks. The WB-57F aircraft will also carry two other experiments, from the University of Hawaii and Virginia Tech, and Caspi serves as the mission scientist, coordinating between NASA and the experiment leads.
“Both projects will require an enormous effort and precise timing to get the data we need,” Caspi said. “I am honored to be part of such exceptionally talented and professional teams, and grateful for everyone’s dedication and hard work.”
Looking at complex motion in the solar corona, at new wavelengths and with new polarization measurements, will help scientists understand why it is so hot. The corona is millions of degrees Celsius, hundreds of times hotter than the visible surface below, which is a longstanding scientific mystery. The corona is also one of the major sources of eruptions that cause geomagnetic storms at Earth. These phenomena damage satellites, cause power grid blackouts and disrupt communication and GPS signals, so it’s important to better understand them.
“The airborne platforms guarantee perfect observing conditions, above any weather and more than 90 percent of Earth’s atmosphere, which can affect image quality,” said SwRI co-investigator Dr. Dan Seaton, who serves as the science lead for both projects. “Combining the airborne mobile data with the CATE 2024 hour-long string of observations will provide a more complete picture of the Sun’s mysterious corona.”
The SwRI-led airborne team includes scientists from the National Center for Atmospheric Research High Altitude Observatory, NASA Langley Research Center, and Predictive Sciences Inc., with collaborators at the Smithsonian Astrophysical Observatory. The SwRI-led CATE 2024 project, funded by NSF and NASA, includes scientists from the National Center for Atmospheric Research, the National Solar Observatory, the University of Colorado, and the Space Science Institute, with collaborators at New Mexico State University and the Livelihoods Knowledge Exchange Network, community leaders at Rice University, Indiana University Bloomington, and the University of Maine, and over 100 community participants in 35 communities along the eclipse path.
Interested parties can find more information about both projects on the group’s website: https://eclipse.boulder.swri.edu.