M&PS: Meteoritics and Planetary Science
MACS: Modular Attitude Control System
MADCS: modular attitude determination and control system
MadOb: Madras Observatory Observations
MadOO: Madras Observatory Astronomical Observations
MAE: Mechanical and Aerospace Engineering
MAEP: Minimum Autoland Entry Point
MAGIC: Major Atmospheric Gamma-ray Imaging Cherenkov Telescope
MAGSAT: magnetometer satellite
MAL: Mobile Airlock
MAN: Microwave Aerospace Navigation
MAPS: Measurement of Air Pollution from Satellites
MARS: Manned Astronautical Research Station
MAS: Medium-Altitude Sensor
MASDC: Military Aircraft Storage and Disposition Center
MASSPO: Manned Spaceflight Support Project Office
MBAC: Marshall Booster Assembly Contractor
MCA: Maximum Crossing Altitude
MCT: Maximum Climb Thrust
MDR: Medium Data Rate
MDRS: Mars Desert Research Station
MECSLSI: Mission Equipment Cargo Shuttle Launch Site
MeeRe: Kenneth Mees Observatory Reprints
MelAR: Melbourne Observatory Annual Report
MelOO: Melbourne Observatory Observations
MEM: Mars Excursion Module
MEM: Meteoroid Exposure Module
MEO: Mid Earth Orbit
MEP: Main Engine Propellant
MERSAT: Meteorology and Earth Observation Satellite
MESELSI: Mission Extension Shuttle Equipment Launch Site
MESELSI: Mission Extension Support Equipment Launch Site
MESSOC: Model Evaluation of Space Station Operations Cost
MEV: Mars Excursion Vehicle
MFA: Manned Flight Awareness
MFC: Manual Flight Control
MFC: Multiple-Flight Computer
MFC: Multiple-Flight Controller
MFCS: Manual Flight Control System
MFF: MDM Flight Forward