The heavily taped foam cooler found dangling from trees along a Castro Valley, California, road Monday evening had all the hallmarks of a dangerous device — including a ring of electrical wiring and a strange humming noise, reported The East Bay Times.
It even bore a note labeling it “dangerous,” reported the publication.
The Alameda County Sheriff’s Office bomb squad, called to the scene at 5:20 p.m. Monday to investigate, blew it up, authorities reported on Twitter. But it wasn’t a bomb.
“Once I pulled it out of the tree, I saw that it was a weather balloon and then I realized all my buddies were going to give me a hard time,” Sgt. Michael Norton of the bomb squad told KGO.
Digital Access for only $0.99
For the most comprehensive local coverage, subscribe today.
The box contained a device used to monitor the ozone layer, called an ozonesonde, launched by San Jose State University students as a science experiment, according to the station.
The device transmits its findings, then when the weather balloon pops, a parachute lands the equipment safely on the ground so it can be recovered, Sen Chiao, director of the Center for Applied Atmospheric Research and Education at the university, told The East Bay Times.
The device, which costs around $1,000, had been labeled “not dangerous,” but part of the tag had fallen off in flight, the publication reported.
“I think that we’re going to put the labeling more clearly on it and very official looking to emphasize this is gathering weather data and it’s not dangerous,” said Alison Bridger of San Jose State University, according to KGO.
It’s not the first time police have blown up scientific equipment gone awry.
In May, police in Prosser, Washington, blew up a high school student’s science fair project that attempted to model an oceanic vent after it was found in a parking lot, reported KTMF. The teen had taken the project out of a vehicle after it began to leak following the fair and forgot about it.
In 2012, a bomb squad detonated a cooler found in an Oregon State University parking lot in Corvallis before discovering it contained oceanographic equipment that had been stolen from the university three days earlier, reported KATU.