NEW YORK: NASA scrubbed the test flight on Monday of its giant Moon rocket because of a temperature issue with one of the four RS-25 engines. Alternative dates for launch of the Artemis 1 mission, an uncrewed flight around the Moon as part of an ambitious program to eventually go to Mars, are September 2 and September 5. NASA’s most powerful rocket yet was set to blast off Monday on a mission to take humans back to the Moon, but fueling the spacecraft gave the US space agency trouble hours before the launch. Fifty years after astronauts last set foot on the moon during the Apollo 17 mission, the Artemis space program was set to get underway with the launch of the uncrewed 322-foot (98-meter) Space Launch System (SLS) rocket at 8:33 am (12:33 GMT) from the Kennedy Space Center in Florida. Tens of thousands of people — including US Vice President Kamala Harris — were expected to gather along the beach to watch the launch, which has been decades in the making.