Anything I can do right now or after a certain amount of years of college. Air force?
If thats what you really want, and are dedicated to getting there, then the most accepted path, is...
Finish college with good enough grades, and MCAT's to get picked up by any medical school.
Then Join the Navy HPSP and pray that you match to the Residency in Aerospace Medicine (RAM) essentially board certified flight surgeon, but really a Preventive medicine residency.
Than apply for the space door gunner program...
Lots of chances that you won't make the cut along the way, and many of them are more based on what happens to be open in the Navy at the particular time that your up for orders, more than how much effort you put into it. Another way to put it, is that you can work as hard as you want, and if the stars don't line up, you don't get what you want.
At this point, it bears mentioning, that two of the astronauts on the Columbia when it burned in over Texas were Navy Physicians.
David M. Brown
Captain, U.S. Navy
Mission Specialist
Laurel Blair Salton Clark
Commander (Captain-Select), U.S. Navy
Mission Specialist
Note also, that Brown was 46 and Salton Clark was 41 so don't expect to just jump into the space program early in your career.
Good luck but don't do military medicine unless theres something that you like about it besides space, because your chances of making it into space are fairly low.
i want out