Former EPA scientists who responded to emergencies are now in the private sector. What does that mean for future crises?

Hidden Guests” explores how the emerging field of microchimerism is upending medicine, genetics, and our sense of self.

Longstanding regulatory and testing gaps have historically been filled by third-party groups with questionable methods.

Things were not going well for Eugene Cernan, who was outside his ship on a spacewalk — just the second time an American astronaut had ever made such a trip. The vagaries of microgravity and Newton’s ...