Star Trek's Captain Kirk would be called Colonel Kirk in the U.S.'s new Space Force, which was created from a rib of the Air Force which used to be the Army, of course, and so uses proper Army rank names—whereas second lieutenants on the Starship Enterprise are called ensigns, after the naval custom, and in the Navy everything is weird. Which is a matter even now being debated in Congress because they, the Congress, seem to have run out of anything useful to do.
A more pressing matter, however, is what's with the jungle-camo uniforms they wear, those Space Forcers, and what are they not telling us here? Are they planning to invade some heavily-foliaged planet in some alternate tropically-warmed galaxy or are they hiding from Martians who are already here? Also, what about 5G?
Fortunately we have retired (Air Force) general David Deptula, dean of the Mitchell Institute of Aerospace Studies to explain, “space may be the final frontier, but our Space Force will not be cruising alien planets like Captain Kirk."
Actually they'll be just, you know, staying here. Like the Army.