SEOUL - South Korean space officials suspended a crucial rocket launch Thursday, after a technical problem halted the countdown just 17 minutes before the scheduled blast-off. “It is impossible to resume the launch sequence today,” Deputy Science Minister Cho Yul-Rae told reporters at the Naro Space Center on the south coast. Cho declined to speculate on the duration of the delay, but officials said the rocket would have to be removed from the launch pad, suggesting it would be at least several days before a new attempt can be made. It was to have been South Korea’s third attempt to put a satellite in orbit and gain entry to an elite global space club that includes Asian powers China, India and Japan.