COLUMBUS, Ohio (AP) — As the sons of a legendary astronaut, Matt Carpenter says he and his little brother "were blessed to grow up around some pretty interesting stuff."

That included the extraordinary headgear the boys would wear during youthful afternoons spent pretending to be fighter pilots.

"When we were young, as far back as I can remember, we would play naval aviators on the couch, and either my brother or I would wear the gold Glenn Navy helmet and one of us would wear a helmet that belonged to my father," Carpenter said.

That's Glenn, as in John Glenn, the first American to orbit eart...