Security Researchers at Symatec Corp published a hack into satellite operators, defense contractors and telecommunications companies in the United States and southeast Asia. The hacking campaign called Thrip was launched from computers in China and appeared to be driven by national espionage goals, such as the interception of military and civilian communications. Thrip was active from 2013 on and then vanished for about a year until the last campaign started a year ago. It was unclear how Thrip gained entry to the latest systems. In the past, it depended on trick emails that had infected attachments or malicious links. This time, it did not infect most user computers, instead moving among servers, making detection harder. In this case, the hackers infected computers that controlled the satellites, so that they could have changed the positions of the orbiting devices and disrupted data traffic, Symantec said.