Ko Arimatsu, an astronomer at Kyoto University in Japan, received an intriguing email a couple of weeks ago: An amateur astronomer in his country had spotted a bright flash in Jupiter’s atmosphere.

Arimatsu, who runs an observation program to study the outer solar system using backyard astronomy equipment, put out a call for more information. Six more reports of the Aug. 28 flash — which, according to Arimatsu, is one of the brightest ever recorded on the giant gas planet — came in from Japanese skywatchers.

Flashes like these are caused by asteroids or comets from the edges of our solar system that impact Jupiter’s atmosphere. "Direct observation of these bodies is virtually impossible, even with advanced telescopes,” Arimatsu wrote in an email. But Jupiter’s gravity lures in these objects, which eventually slam into the planet, "making it a unique and invaluable tool for studying them directly,” he said.