In 1994, a 6.7-magnitude earthquake rumbled through Los Angeles at 4:30 a.m. The shaking woke residents, who discovered the power had gone out citywide.
Some left their houses or peered outside to check on the neighborhood. It was eerily dark — no streetlights and few cars at that late hour.
They looked up at the sky. It was flush with cosmic bodies that had been invisible up to that point — twinkling stars, clustered galaxies, distant planets, even a satellite or two. Then some people became nervous. What was that large silvery cloud that trailed over the city? It looked so sinister they called 911.