Almost a dozen scientists related to nuclear and space defense programs tied to NASA, SpaceX, and Blue Origin are dead or missing in cases as far back as 2022, and they’ve gone largely unnoticed by authorities and the public—until now. The House Oversight Committee formally demanded answers from four federal agencies Monday on the deaths and disappearances of at least 11 American scientists and researchers with ties to NASA, nuclear research, and classified defense programs—several of them direc...