Are Jeff Bezos and Richard Branson (among others) astronauts? Does any flying to space makes a human an astronaut, also when they are dead weight? Assuming that the definition of space (Kármán line or 50 miles) is irrelevant.
tl;dr Branson and Bezos may or may not be awarded astronaut wings by the United States Government, if they submit an application to the Federal Aviation Administration and it is approved. But, they can call themselves what they like.
"Astronaut" is a word and anyone can use it to mean anything they like. This question invites argument about definitions, which by definition is pointless unless it is narrowly defined.
The criteria for being awarded astronaut wings from the United States Government are not fuzzy - but they have changed over time. If you choose to restrict usage of the word "astronaut" to mean "a person who has been awarded astronaut wings from the United States Government" these are the current criteria for being an astronaut:
To earn an astronaut badge, a U.S. Air Force or U.S. Navy and Marine Corps officer must complete all required training and participate in a space flight more than 50 miles (80 kilometers) above the Earth.
The U.S. Army has awarded the badge to officers that have orbited the Earth.
(Note that Army astronaut wings were only created in 1983).
NASA astronaut wings are "issued in two grades, silver and gold, with the silver pin awarded to candidates who have successfully completed astronaut training and the gold pin to astronauts who have flown in space." Note silver = astronaut candidate training complete, gold = astronaut. NASA payload specialists received yet a third version of the badge, not astronaut wings at all.
From Mike Mullane's (highly-recommended) memoir Riding Rockets about his first flight
Hank gave us a countdown. "Here it comes...forty-eight...forty-nine...fifty miles. Congratulations, rookies. You're officially astronauts."
The current NASA astronaut website says
The term "astronaut" derives from the Greek words meaning "space sailor," and refers to all who have been launched as crew members aboard NASA spacecraft bound for orbit and beyond.
- The FAA has issued astronaut wings in the past to fliers who submit an application that was judged to meet their criteria. Note that between Branson and Bezos's flights, they tightened said criteria to require demonstration of "activities during flight that were essential to public safety, or contributed to human space flight safety." Thanks to Jörg W Mittag for explaining this to me via comments and providing a link to the criteria.
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