For centuries, nobody knew just what the aurora borealis — a.k.a. the northern lights — really was.
Last year, a consortium of scientists used NASA satellites to monitor conditions 70,000 kilometers above the earth and found that the green lights are really pent-up electric currents racing across the ionosphere. (They’re caused by massive eruptions of magnetic energy set off when charged particles from the sun collide with our atmosphere.)
Unfortunately, the phenomenon’s visible only from the North Pole — and that makes these time-lapse videos of recent auroras all the more fantastic: We can finally appreciate their surreal beauty without freezing our butts off.
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