A NASA intern has discovered a new type of aurora in 3-year-old video footage of the Arctic sky. With the help of NASA scientists and a satellite, Jennifer Briggs, a physics student at Pepperdine University, connected the unusual aurora to a sudden retreat in Earth's magnetic field. It's the first time scientists have seen an aurora caused solely by a compression of Earth's magnetic field. Usually, auroras dance across the sky when a lot of high-energy particles from the sun, called solar wind, flood over Earth. But in this case, the sun didn't show any unusual or heightened activity.