The sunspot AR2993 erupted with two M1 flares in quick succession, according to spaceweather.com. Solar flares are eruptions of electromagnetic radiation; M-class flares are moderate-sized flares that can disrupt some radio frequencies and sometimes expose astronauts in space to higher-than-usual levels of radiation.
It’s been a busy few weeks for the sun, with multiple active sunspots sending off flares. Solar activity occurs in regular 11-year cycles, which have been recorded since 1775. The sun is currently in Solar Cycle 25 and is in a period of ramping up its activity. Solar Cycle 25 is expected to peak in late 2024 or early 2025, meaning that the frequency of sunspots, solar flares and CMEs are expected to increase.
Some of those flares and CMEs are likely to be more impactful than the middling double-M1s the sun just threw out. Just last week, on April 19 and 20, a different sunspot (AR2992) erupted with a powerful X-class flare. X-flares are 10 times as powerful as M-class flares and can cause radiation storms that disrupt satellites, radio communications and even the power grid on Earth. Luckily, Earth did not bear the full brunt of last week’s X-flare, as the sunspot was not facing directly toward the planet.
Large solar flares and CMEs can also trigger gorgeous auroras farther south from Earth’s poles than is typical. Solar particles from the sun interact with the magnetic fields surrounding Earth, exciting air molecules in the upper atmosphere and causing them to give off photons of light. The result? Shifting curtains of light in greens, blues and pinks.
As the sun continues its unsettled activities, aurora forecasts can be found at the National Oceanic and Atmospheric Administration (NOAA) Space Weather Prediction Center.