GOHEUNG, South Korea—South Korea’s first domestically built space rocket blasted off on Thursday, but failed to fully place a dummy satellite into orbit, delivering mixed results for a test launch that represents a major leap for the country’s ambitious space plans. The three-stage KSLV-II Nuri rocket, emblazoned with the national flag, rose on a column of flame from its launch pad at Naro Space Center at 5 p.m. (0800 GMT). The Nuri, or “world,” rocket is designed to put 1.5-tonne payloads into orbit 370 to 500 miles above Earth as part of a broader space effort that envisages the launch of satellites for surveillance, navigation, and communications, and even lunar probes. President Moon Jae-in, who watched the launch from the space center, said the rocket completed its flight sequences but failed to place the test payload into orbit. “Unfortunately, we did not fully reach our goal,” he said in a …