NASA has begun filling its moon rocket gas tank for humanity’s first lunar trip in more than half a century. The 32-story rocket is due to blast off with four astronauts Wednesday evening from Florida’s Kennedy Space Center. First, the launch team has to load it with more than 700,000 gallons of fuel. Tensions were high Wednesday morning as hydrogen fuel started flowing into the rocket. Dangerous hydrogen leaks erupted during a countdown test earlier this year, forcing a lengthy flight delay. Three Americans and one Canadian make up the Artemis II crew. England’s King Charles III wishes them the best.