NASA on Thursday will ignite the engines on a rocket that Boeing built to eventually launch Artemis missions to the moon after a previous test in January was cut short. NASA plans to conduct the engine test during a two-hour window that starts at 3 p.m. EDT (1900 GMT) at its Stennis Space Center in Mississippi. The hot-fire test of the core stage of the Space Launch System (SLS) rocket will simulate a launch by firing the engines while anchored to a tower. NASA aims to return U.S. astronauts to the moon by 2024 but the SLS program is three years behind schedule and nearly $3 billion over budget. The last astronaut to walk on the moon was Eugene Cernan in December 1972. NASA previously tested all four engines of its behemoth core stage in January, but the test lasted for about a minute—well short of the roughly four minutes …