Friday launch opens weekend doubleheader for SpaceX

By Dana Hull
SAN FRANCISCO — The year’s not half over, and Elon Musk’s Space Exploration Technologies Corp. is about to launch more missions than it completed in all of 2016.
SpaceX successfully fired up a Falcon 9 rocket for the eighth time this year on Friday, matching its flight total for all of last year. Its next launch is scheduled only two days later, with the ramped-up cadence putting the company on track to achieve the 20 to 24 total missions it’s targeting for t