Auroras filled much of the world\u2019s skies for several nights in mid-May as a historic geomagnetic storm<\/a> coursed 100 kilometers above our heads. Being able to see auroras so deep into the tropics was possibly a once-in-a-lifetime experience, but there will almost certainly be more strong geomagnetic storms later this year, giving hope to aurora watchers around the world that more dazzling lights are possible in the near future.<\/p>\n This is because we\u2019re quickly approaching solar maximum, the peak of our star\u2019s predictable 11-year cycle of activity. Solar flares and coronal mass ejections, or CMEs, are more common during and just after solar maximum, and it\u2019s these that are responsible for vivid auroras.<\/p>\n The great aurora show on May 10, 2024, was the result of three CMEs that surged out of the sun\u2019s outer atmosphere and headed toward Earth. A CME is a collection of magnetized plasma ejected from the sun\u2019s exceptionally hot outer atmospheric layer, the corona, as a result of a disruption in the sun\u2019s magnetic field<\/a>.<\/p>\n On May 10, each successive CME moved a little faster than the one before it, allowing all three bursts of charged particles to merge before washing over Earth\u2019s atmosphere. The combined energy of three CMEs hitting our planet at once unleashed an aurora show for the ages.<\/p>\n![\"Image](\"https:\/\/media.wired.com\/photos\/665112aedd315f78857e18bb\/master\/w_1600%2Cc_limit\/_NASA-SOHO_1.jpg\")