WASHINGTON — Blue Origin has traced the explosion of its New Glenn rocket during a static-fire test in May to a valve in the rocket’s BE-4 engine, an issue that could also affect United Launch Alliance’s Vulcan Centaur. “The anomaly originated at the main oxygen valve on one of the BE-4 engines, which was later confirmed by hardware recovery and inspections,” he said. “Extensive component-level and engine hotfire tests have been conducted to understand the failure mode better and inform mitigations.” Because the problem is with the BE-4 engine, it may also be an issue for United Launch Alliance, whose Vulcan rocket uses the engine in its first stage. Limp did not provide a schedule update when he discussed the BE-4 investigation.