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Acronyms
IOV
In-Orbit Validation
IPTA
International Pulsar Timing Array
IRNSS
Indian Region Navigation Satellite System
ISS
International Space Station
IT
Italian National Institute of Metrological Research
ITRF
International Terrestrial Reference Frame
ITRS
International Terrestrial Reference System
ITS
Instantaneous Terrestrial System
ITT
International Telephone and Telegraph Corporation
ITU
International Telecommunication Union
IUGG
International Union of Geodesy and Geophysics
IURS
International Radio Science Association
JATO
Jet-Assisted Takeoff
JAXA
Japan Aerospace Exploration Agency
JPL
Jet Propulsion Laboratory
JPO
Joint Program Office
KIK
Command and Measurement Complex (the acronym in Russian)
LEO
Low Earth Orbit
LGM
Little Green Man
LJ
Little Joe Rockets
LLR
Lunar Laser Ranging
LM
Lunar Module
LMC
Large Magellanic Cloud
LMXB
Low-Mass X-ray Binary
LORAN
Long-Range Navigation
MADAN
Multi-mission Attitude Determination and Autonomous Navigation
MANS
Microcosm Autonomous Navigation System
MEMS
Micro-Electro-Mechanical System
MEO
Medium Earth Orbit
MIT
Massachusetts Institute of Technology
MJD
Modified Julian Day
MLS
Microwave Landing System
MOST
Molonglo Observatory Synthesis Telescope
NACA
National Advisory Committee on Aeronautics
NANOGrav
North American Nanohertz Observatory for Gravitational Waves
NASA
National Astronautics and Space Administration (US)
NAVSTAR
Navigation Satellite Time and Ranging
NCST
Naval Center for Space Technology (US)
NGA
U.S. National Geospatial-Intelligence Agency
NICER
Neutron-star Interior Composition Explorer
NII
Scientific Research Institute (the acronym in Russian)
NIP
Scientific Measurement Stations (the acronym in Russian)
NIST
National Institute of Standards and Technology (US)
NNSS
Navy Navigation Satellite System
NPL
British National Physical Laboratory