Again, Go to AFI 36-2205 and it spells out all the technical degrees required. No need to speculate.
You need adobe to view the document- Chapter 2 is the Astronaut chapter. Chapter one covers Pilot, Nav and Air Battle Manager applications via AF
The breakdown between Air Force and Navy Astronauts is somewhat even (and there have been several Army Aviators in the program).
Of the current 108 (before the current selection) active astronauts, there are 23 members fromthe Air Force, 1 from the Air Force Reserves, 6 Army officers, 1 Coast Guardsman, 6 Marines, 27 from the Navy, and 3 from the Navy Reserves- and 41 civilians
-link to prior Navy astronauts http://www.history.navy.mil/faqs/faq88-1.htm
- There are some 54 former astronauts as well as 23 current astronauts and one astronaut candidate who also wear Air Force blue.
Here is a decent story about the most recent Board of selection and the training process
" Duane Ross has 37 years of experience at Johnson Space Center in Houston selecting and training astronauts. NASA receives about 3,000 applications every two years when it selects its next class, said the astronaut candidate selection and training manager.
Out of the thousands, 100 will be interviewed and about 10 will be selected. Both civilian and military applicants are considered. "
Ciao, and Hook 'em Horns,
Capt-AWACS, Seven Continents Down, None to Go