WTTM means WIYN Wisconsin, Indiana University, Yale University, and NOAO National Optical Astronomy Observatories Observatory Tip-Tilt Module in Astronomy
Similar to WTTM
ASCH - Alien Societies Culture And HistoryASLV - Advanced Satellite Launch Vehicle
AST - Apparent Solar Time
ASWG - Astronomical Science Working Group
ASWG - ATST Advanced Technology Solar Telescope Science Working Group
ATM - Apollo Telescope Mount
ATM - Amateur Telescope Maker
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