NASA began fueling the Artemis 1 moon rocket, NASA’s first Space Launch System (SLS), early Saturday to launch an unmanned Orion spacecraft to the Moon from Pad 39B here at the Kennedy Space Center at 2:17 p.m. EDT (1817 GMT). But a persistent liquid hydrogen fuel leak detected has slowed launch preparations. NASA has a two-hour window for the mission to launch, with a promising weather forecast of between 60% and 80% “go,” the agency said. You can watch it live online. The hydrogen leak was first detected at 7:15 am. EDT (1115 GMT) as NASA began filling the massive SLS rocket with the 730,000 gallons of liquid hydrogen and liquid oxygen propellant required for launch. The leak is located at the connection point of an 8-inch hydrogen fuel line near the engine bay at the base of the 32-story rocket. Engineers first tried to heat the connector and cool it with cold fuel to stop the leak, then tried to blow it with helium to solve it. Both attempts failed, with NASA again trying this first heat and cool method to stop the leak. A smooth refueling process for Artemis 1 could take up to four hours, but there isn’t much room in the schedule for delays, NASA said. It was during the refueling (or “tank” as NASA calls it) process that launch controllers hit a snag during the agency’s first launch attempt on Monday (August 29). NASA aborted this launch attempt when it could not confirm that one of the SLS core stage’s four main RS-25 engines was at the proper temperature of minus 420 degrees Fahrenheit for launch. The agency eventually determined that a bad sensor caused the problem and implemented solutions for Saturday’s launch attempt. On Saturday, NASA planned to start the main engine cooling process earlier to give the SLS rocket’s engines more time to reach their target temperature. But this process has been delayed due to the fuel leak. NASA’s Artemis 1 mission is the first test flight for NASA’s Artemis program to return astronauts to the Moon by 2025. The mission is a 37-day trip around the moon to verify that the Orion spacecraft and SLS rocket are safe for the astronauts. The mission will also deploy 10 Artemis cubes en route to the moon and conduct a series of experiments to measure the astronauts’ experience in the Orion spacecraft. Artemis 1 is scheduled to return to Earth on October 11 with a dive in the Pacific Ocean off the coast of California. If all goes well, NASA aims to launch a crew around the Moon on the Artemis 2 mission in 2024, followed by the Artemis 3 lunar landing in 2025. Editor’s note: This story, originally published at 7 a.m. ET, has been updated to include details about the fuel leak NASA is working to stop on the SLS rocket. Follow us Live updates on the Artemis 1 mission page for the latest news on the Artemis 1 mission. Visit Space.com for live webcasting. Email Tariq Malik at [email protected] or follow him @Donald Trump. Follow us @Spacedotcom, Facebook and Instagram.
