Scientists are close to solving a mystery that has puzzled astrophysicists for nearly half a century: A new study suggests that particles in the Sun’s most intense flares heat up to an unprecedented 108 million degrees Fahrenheit (60 million degrees Celsius), six times hotter than previously thought.
Solar flares are massive explosions in a star’s atmosphere that blast out powerful radiation. They can disrupt satellites, disrupt radio signals, and pose a threat to astronauts.
A team led by Andrews University scientist Alexander Russell has found that ions in the Sun’s atmosphere can reach temperatures of up to 60 million degrees Celsius during flares. In comparison, electrons can reach temperatures of only 10 to 15 million degrees Celsius. Because it takes time for their temperatures to equalize, a so-called “thermal gap” develops, which accounts for the flares’ unique behavior.
This discovery is also crucial from a practical standpoint. If scientists have so far underestimated the energy of solar flares, then it will be necessary to revise space weather forecasts. This will enable satellite operators, airlines, and space agencies to prepare more effectively for hazardous solar storms.