On May 15, 2024, NASA’s Solar Dynamics Observatory, which continuously monitors the Sun, captured images of two powerful X-class solar flares. The first of these was classified as an X3.4 eruption and peaked at 4:37 am. The second flare, classified as X2.9, peaked at 10:38 ET.

Solar flares are intense bursts of radiation resulting from the release of magnetic energy associated with sunspots. These bursts can be seen across the entire electromagnetic spectrum, from radio waves to gamma rays, and are among the most powerful events in the Solar System. When solar flares target Earth, they can affect our planet in a variety of ways, including disrupting satellite communications, affecting the power grid, and enhancing the aurora borealis (northern and southern lights).

The impact on Earth primarily involves the interaction of solar radiation with the Earth’s magnetic field, which can lead to geomagnetic storms. These storms can disrupt technology and infrastructure and expose astronauts and high-altitude flights to high levels of radiation.

Solar flares are classified according to their intensity at X-ray wavelengths, from class A (weakest) to class X (strongest). The energy output of each class increases tenfold, and a finer scale from 1 to 9 within each class further differentiates the power of the flash. Class X flares are the largest explosions in the Solar System and can cause planet-wide radio blackouts and long-lasting radiation storms.

NASA’s Solar Dynamics Observatory (SDO) is a mission designed to understand the Sun’s impact on Earth and near-Earth space by examining the solar atmosphere at small spatial and temporal scales and at many wavelengths simultaneously. Launched on February 11, 2010, SDO is part of NASA’s Living with a Star (LWS) program.

The observatory is equipped with an array of instruments that provide observations that lead to a more complete understanding of the solar dynamics that drive the variability of the Earth’s environment. One of these tools is the Atmospheric Imaging Assembly (AIA), which produces images of the solar disk at different wavelengths every 12 seconds, providing information about the structure and dynamics of the solar corona. Another important instrument, the Helioseismic and Magnetic Imager (HMI), studies solar variability and characterizes the Sun’s inner layer and various components of magnetic activity.

SDO data is vital to helping scientists understand the Sun’s effects on Earth and space by observing solar flares, coronal mass ejections (CMEs), and other solar events. This information is critical to improving the ability to predict space weather events that could impact the operations of satellites, astronauts, and ground systems.