NASA's giant moon rocket is headed back to the hangar for more repairs. The space agency said Sunday it's targeting Tuesday for the four-mile trek, weather permitting. NASA had barely finished a repeat fueling test last week to ensure hydrogen fuel leaks were plugged when another problem cropped up. This time, the rocket's helium system malfunctioned, further delaying astronauts' first trip to the moon in decades. The earliest three Americans and one Canadian assigned to the Artemis II mission can launch is April.