Solar flares—sudden bursts of electromagnetic radiation from the Sun—can emit dangerous levels of energy strong enough to reach Earth’s atmosphere. Predicting a solar flare, however, is not as easy as predicting a sunny day.
A research team co-led by heliophysicist Emily Mason of Predictive Sciences Inc. identify the type of solar activity in the Sun’s atmosphere that may precede and thus indicate a future solar flare. Their research, detailed in a December 6 study published in Astronomical Journal Letters and launched on January 15 during the 245th meeting of the American Astronomical Society, it has a significant impact on the effort to keep astronauts and space assets safe.
Indeed, predicting solar flares is critical to protecting both people and technology from the Sun’s volatile outbursts. Solar flares can disrupt satellite communications, GPS systems, and power grids on Earth, while exposing astronauts and spacecraft to dangerous levels of radiation. Therefore a reliable warning system may be a welcome tool to reduce the risks of space weather.
Using NASA’s Solar Dynamics Observatory, Mason and his colleagues analyzed the flickering of coronal loops—arch-like structures in the Sun’s outer atmosphere, known as the corona—that lead to 50-magnitude solar flares. Coronal loops exist in the same magnetic fields of the Sun that also cause solar flares, according to a NASA statement. The researchers observed that the brightness of the coronal loops in excess ultraviolet light was significantly different in the hours preceding the large opening near the coronal loops than in the non-exposed regions.
“We found that some extreme ultraviolet light above the active regions dims inappropriately a few hours before a solar flare,” Mason explained in a statement. “The results are very important for understanding combustion and may improve our ability to predict hazardous weather in the atmosphere.”
Researchers suggest that looking at variations in ultraviolet light in the coronal loops can predict upcoming solar flares two to six hours in advance with 60 to 80 percent accuracy, which—if proven true—is more accurate than previously attempted forecasting methods.
“The Sun’s corona is a dynamic environment, and each solar flare is like a snowflake — every flare is different,” said Kara Kniezewski of the Air Force Institute of Technology, who also led the study. “We find that searching for periods of ‘chaos’ in coronal loop emissions, rather than specific trends, provides a more consistent metric.”
Vadim Uritsky of NASA’s Goddard Space Flight Center, who also participated in the study, envisions creating a “well-tested and, ideally, simple. [solar flare] the index is ready to jump from research to practice.” The researchers also suggest that the stronger the flare, the earlier the flickering peaks, but admit that more analysis is needed to confirm this point.
Scientists have been trying to predict solar flares for decades. If recent research proves to be true, the blinking coronal loops may serve as a flashing warning signal to humans and technology in a dangerous way.