Investigation will ground rockets for 'a number of months'- SpaceX

CAPE CANAVERAL, Fla. (Reuters) - SpaceX President Gwynne Shotwell said an investigation into Sunday's explosion shortly after launch of one of the company's Falcon 9 rockets will ground the rockets for several months but less than a year. "I imagine a number of months or so," Shotwell said at a news conference. "It's certainly not going to be a year." The rocket was on a mission to resupply the International Space Station. SpaceX founder Elon Musk said on Twitter a preliminary analysis indicated a problem with the rocket's upper-stage engine. (Reporting by Irene Klotz; Editing by Eric Beech and Frances Kerry)