Fig. 1: Distribution of age at selection and first flight for NASA astronauts (green and blue), and age at first flight for commercial spaceflight participants (orange).
From: A demographic comparison of NASA astronauts and commercial spaceflight participants
NASA astronauts are selected within a relatively narrow age range (26‒47 yr), then, after a minimum training period, complete their first flight between 2 and 19 years later. Commercial astronauts have had a much wider age range (18‒90 yr) and typically have only months between being announced as a spaceflight participant and going to space.
