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March 10, 20252 min readEarth May Soon Get Early Solar Flare WarningsFlickering loops in the suns corona may appear before dangerous solar activityBy Chris Simms edited by Sarah Lewin FrasierAnalyzing huge loops in the suns corona (its atmosphere) can predict potentially dangerous solar flares. DETLEV VAN RAVENSWAAY/Science SourceSolar flares are bursts of radiation from the suns surface, sometimes followed by a bubble of magnetized plasma particles called a coronal mass ejection (CME). If they happen to spray out in Earths direction, CMEs can cause geomagnetic storms that damage power systems on the ground or spacecraft in orbit. And solar flare radiation itself can disrupt communication networks and satellite operations.Unfortunately, solar scientists cannot reliably predict when the sun will belch out a flare. After one is observed, every minute counts in the ensuing scramble to adjust power grids or move satellites before they get damaged.Now researchers have used data from NASAs Solar Dynamics Observatory to show that distinctive flickering in the huge loops of roiling plasma that arch up out of the suns atmosphere, called the corona, seems to signal that a large flare could soon occur. This link could help researchers brace for the flare and look out for signs that an incoming CME could hit Earth within a couple of days.On supporting science journalismIf you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.Emily Mason, a heliophysicist at San Diego-based research firm Predictive Science, and her colleagues observed coronal loops in magnetically active regions where 50 strong solar flares occurred. They found that the loops ultraviolet light output varied erratically a few hours before a flare, the team told a recent meeting of the American Astronomical Society in Maryland. It gives us one to two hours warning, with 60 to 80 percent accuracy, that a flare is coming, Mason says.If we want to be able to predict solar storms earlier, then we have to predict when the flare will happen, says Mathew Owens, a space physicist at the University of Reading in England. Small gains there are valuable.Crucially, the researchers used a near-real-time data stream with just an hours lag rather than working with data that have been processed to improve quality, which can take weeks. Mason and her team observed flares on the suns outer edges from our perspective, or limbs, because that is where their light can best be seen from Earth. Flares on the suns eastern limb will head away from Earth as the sun rotates, but those on the western limb may hit the planets atmosphere, Mason says.For now our viewpoint means we cant easily see loops emanating from elsewhere on the sun. But the European Space Agency is planning to launch a spacecraft called Vigil in 2031 that should give us a side-on perspective. Being able to see the sun from more different angles is the single most important thing that we can do to improve our predictions, Mason says. She hopes predicting big flares can help keep astronauts and electrical systems safe.