Greece saw a power failure over the weekend that caused Athens' main flight radar to go down, causing flight delays for more than an hour—and it was all thanks to a balloon. The "aluminized" helium balloon first caused a 13-minute power outage, and the radar shut down 40 minutes later due to an electrical failure, reports the Telegraph, citing local reports. Officials confirmed the problem, but said no flights were in danger. (More power outage stories.)