Question: What are the military ranks of Tucker, Watts, and Halsey? It's stated that Sharpe & Davis are Colonels, and Lev is a Colonel in the Russian military. Gruber is referred to as Sergeant, but so far, the ranks of the last 3 weren't mentioned.
Answer: They're introduced as "Nasa Pilot Watts" and "Nasa Pilot Tucker", they're likely civilians. There are civilian Astronauts in the Space program. There's even wings for a civilian pilot.
Question: Why is Colonel Sharp so intent on following the President's order to remote detonate the nuke? He knows the mission won't be successful unless they drill the hole first. Does he really think being court martialed for defying an executive order will be worse than an extinction-level event?
Answer: Given his choices, what he views as certain failure of the drilling or trying to detonate the bomb on the surface, he decides to follow orders rather than wait for the drilling to fail.
Chosen answer: It is not mentioned in the movie. However, we can assume that Tucker and Watts are mid-grade officers. They would be below the commanding colonels, but above ensigns because of their flight status. Likely they are lieutenants or captains.
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