GMT means Greenwich Mean Time
replaced by UT in 1928, then UTC in 1960 in
NASA
Similar to GMT
2IC - Second In Command
2M - Micro Miniature
2MASS - Two Micron All-Sky Survey
2STO - Two Stage To Orbit
3-DOF - Three Degree Of Freedom
3AAL - Three Axis Acoustic Levitator
6-DOF - Six Degree Of Freedom
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