Angelenos will get their chance Friday to witness a rare celestial event when the shadows of three of Jupiter’s largest moons will fall upon Jupiter at the same time. Griffith Observatory will stay open one hour later than normal to allow visitors who are already at the park to watch the triple-shadow transit as Jupiter’s three moons – Io, Europa, and Callisto – will cross the planet’s disk throughout the evening. Three moon shadows will not appear simultaneously on Jupiter again, from Los Angeles, until 2032, according to the Observatory. As if the triple shadow transit weren’t enough, there will...