(UPDATE) The sun launched a massive solar flare yesterday that’s headed in Earth’s direction – the strongest storm seen in the current weather cycle. The volley of radiation may trigger the northern lights if it collides with our atmosphere, and could cause major issues for power grids, experts suggest.

NASA’s Solar Dynamics Observatory, which tracks the Sun’s activity, captured an image of the event at 11:35 a.m. EST (4:35 p.m. BST) on Thursday. It has already caused a temporary, but strong, radio blackout in parts of South America, according to the U.S. Space Weather Prediction Center (SWPC).

The flare is the result of a coronal mass ejection (CME) – a huge expulsion of plasma from the Sun’s outer layer, called the corona. In a blog post, Nasa said that the “significant” flare has been classified as an X1. Flares are ranked by letter, with the biggest labeled as “X-class.”


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The smallest flares are “A-class.” Higher numbers designate more intense flares. Nasa logged an X28 in 2003, though an X1 is still a significant eruption. The flare is expected to hit Earth over the weekend, meaning it could land on Halloween on October 31. Dr. Tamitha Skov, a space weather physicist, said on Twitter:

“A direct hit for Halloween! The solar storm launched during the X-flare today is indeed Earth-directed! “NASA predictions confirm impact by early October 31. “Expect aurora to mid-latitudes, as well as GPS reception issues and amateur radio disruptions on Earth’s nightside!” READ MORE