| M-Cubed | October 28, 2011 | University of Michigan | Delta II |
| M-Cubed-2 | December 6, 2013 | University of Michigan | Atlas V 501 |
| M6P | April 1, 2019 | Kongsberg NanoAvionics | Polar Satellite Launch Vehicle-QL |
| MABES | August 12, 1986 | National Space Development Agency | H-I |
Magellan | May 4, 1989 | Jet Propulsion Laboratory | Space Shuttle |
Magion 1 | October 24, 1978 | — | Kosmos-3M |
Magion 2 | September 28, 1989 | — | Tsyklon-3 |
Magion 3 | December 18, 1991 | — | Tsyklon-3 |
Magion 4 | August 2, 1995 | — | Molniya-M |
Magion 5 | August 29, 1996 | — | Molniya-M |
| MAGNARO | October 12, 2022 | Nagoya University | Epsilon |
| MAGNARO-II Tigris | April 23, 2026 | Nagoya University | Electron |
| Magnetic Storm Satellite (MSS) | January 1, 2000 | — | — |
| Magnetospheric Multiscale 1 | March 13, 2015 | National Aeronautics and Space Administration | Atlas V 421 |
| Magnetospheric Multiscale 2 | March 13, 2015 | National Aeronautics and Space Administration | Atlas V 421 |
| Magnetospheric Multiscale 3 | March 13, 2015 | National Aeronautics and Space Administration | Atlas V 421 |
| Magnetospheric Multiscale 4 | March 13, 2015 | National Aeronautics and Space Administration | Atlas V 421 |
| Magnum | August 3, 1965 | United States Air Force | Atlas SLV-3 Agena-D |
| MAGPIE | 2029 | ispace EUROPE S.A. | — |
MagSat | October 30, 1979 | — | Scout G-1 |
| Mahda | January 28, 2024 | — | Simorgh |
| Malligyong-1 #1 | May 30, 2023 | National Aerospace Development Administration | Chŏllima-1 |
| Malligyong-1 #2 | August 23, 2023 | National Aerospace Development Administration | Chŏllima-1 |
| Malligyong-1 #3 | November 21, 2023 | National Aerospace Development Administration | Chŏllima-1 |
| Malligyong-1-1 #1 | May 27, 2024 | National Aerospace Development Administration | North Korean kerolox space launch vehicle |
| Mandrake 2 Able | June 30, 2021 | — | Falcon 9 |
| Mandrake 2 Baker | June 30, 2021 | — | Falcon 9 |
| MANTIS | November 11, 2023 | — | Falcon 9 |
| MaqSat-B | October 30, 1997 | Arianespace | Ariane 5G |
| MaqSat-H | October 30, 1997 | Arianespace | Ariane 5G |
MarCO-A | May 5, 2018 | Jet Propulsion Laboratory | Atlas V 401 |
MarCO-B | May 5, 2018 | Jet Propulsion Laboratory | Atlas V 401 |
| MARECS 1 | December 20, 1981 | European Space Agency | Ariane 1 |
| MARECS 2 | November 10, 1984 | European Space Agency | Ariane 3 |
| MARECS B | September 10, 1982 | European Space Agency | Ariane 1 |
Mariner 1 | July 22, 1962 | Jet Propulsion Laboratory | Atlas-Agena B |
Mariner 10 | November 3, 1973 | Jet Propulsion Laboratory | Atlas SLV-3D Centaur-D1A |
Mariner 2 | August 27, 1962 | Jet Propulsion Laboratory | Atlas-Agena B |
Mariner 3 | November 5, 1964 | National Aeronautics and Space Administration | Atlas-Agena D |
Mariner 4 | November 28, 1964 | Jet Propulsion Laboratory | Atlas-Agena D |
Mariner 5 | June 14, 1967 | Jet Propulsion Laboratory | Atlas SLV-3 Agena-D |
Mariner 6 | February 25, 1969 | Jet Propulsion Laboratory | Atlas-Centaur |
Mariner 7 | March 27, 1969 | Jet Propulsion Laboratory | Atlas-Centaur |
Mariner 8 | May 9, 1971 | Jet Propulsion Laboratory | Atlas-Centaur |
Mariner 9 | May 30, 1971 | Jet Propulsion Laboratory | Atlas SLV-3C Centaur-D |
| Marisat 1 | February 19, 1976 | — | Delta 2000 |
| Marisat 2 | June 10, 1976 | — | Delta 2000 |
| Marisat 3 | October 14, 1976 | — | Delta 2000 |
| Maritime Monitoring and Messaging Micro-Satellite | June 22, 2016 | Canadian Space Agency | Polar Satellite Launch Vehicle-XL |
| Maroc-TUBSAT | December 10, 2001 | — | Zenit-2 |
Mars 1 | November 1, 1962 | — | Molniya |
Mars 1969A | March 27, 1969 | — | Proton-K |
Mars 1M | October 10, 1960 | — | — |
Mars 1M No.1 | October 10, 1960 | — | Molniya |
Mars 1M No.2 | October 14, 1960 | — | Molniya |
| Mars 2 | May 19, 1971 | Soviet Union | Proton-K |
| Mars 2 Lander | May 19, 1971 | — | Proton-K |
Mars 2020 | July 30, 2020 | National Aeronautics and Space Administration | Atlas V 541 |
Mars 2M No.522 | April 2, 1969 | — | Proton-K |
| Mars 2MV-3 No.1 | November 4, 1962 | — | Molniya |
| Mars 2MV-4 No.1 | October 24, 1962 | — | Molniya |
| Mars 3 | May 28, 1971 | Soviet space program | Proton-K |
| Mars 3 Lander | May 28, 1971 | — | — |
Mars 4 | July 21, 1973 | NPO Lavochkin | Proton-K |
Mars 5 | July 25, 1973 | NPO Lavochkin | Proton-K |
Mars 6 | August 5, 1973 | — | Proton-K |
| Mars 6 Flyby Bus | August 5, 1973 | — | Proton-K |
Mars 7 | August 9, 1973 | — | Proton-K |
| Mars 94 (Cancelled) | September 21, 1994 | — | — |
Mars 96 | November 16, 1996 | Roscosmos State Corporation | Proton-K |
| Mars 96 Penetrator | November 16, 1996 | — | Proton-K |
| Mars 96 Surface Station | November 16, 1996 | — | Proton-K |
Mars Climate Orbiter | December 11, 1998 | National Aeronautics and Space Administration, Jet Propulsion Laboratory | Delta II |
Mars Express | June 2, 2003 | European Space Agency | Soyuz-FG |
Mars Global Surveyor | November 7, 1996 | National Aeronautics and Space Administration | Delta II |
Mars Hope | July 19, 2020 | Mohammed bin Rashid Space Centre | H-IIA |
Mars Observer | September 25, 1992 | Jet Propulsion Laboratory | Commercial Titan III |
Mars Orbiter Mission | November 5, 2013 | Indian Space Research Organisation | Polar Satellite Launch Vehicle-XL |
Mars Pathfinder | December 4, 1996 | National Aeronautics and Space Administration, Jet Propulsion Laboratory | Delta II |
Mars Polar Lander | January 3, 1999 | Jet Propulsion Laboratory, National Aeronautics and Space Administration | Delta II |
Mars Reconnaissance Orbiter | August 12, 2005 | Jet Propulsion Laboratory | Atlas V 401 |
Mars Science Laboratory | November 26, 2011 | National Aeronautics and Space Administration | Atlas V 541 |
| Mars Surveyor 2001 Rover | April 5, 2001 | — | Delta II |
| Mars7FlybyBus | August 9, 1973 | — | Proton-K |
| MARScom | December 10, 2006 | United States Naval Academy | Space Shuttle |
Martian Moons eXploration | October 19, 2026 | Japan Aerospace Exploration Agency | H3 Launch Vehicle |
| MaSat-1 | February 13, 2012 | Budapest University of Technology and Economics | Vega |
| MASCOT | December 3, 2014 | — | H-IIA |
| MATS | November 4, 2022 | OHB Sweden | Electron |
MAVEN | November 18, 2013 | Lockheed Martin Space | Atlas V 401 |
| Max Valier Sat | June 23, 2017 | — | Polar Satellite Launch Vehicle-XL |
Maya-1 | June 29, 2018 | University of the Philippines Diliman | Falcon 9 Full Thrust |
| Maya-2 | February 20, 2021 | University of the Philippines Diliman | Antares |
| Maya-3 | August 29, 2021 | University of the Philippines Diliman | Falcon 9 Block 5 |
| Maya-4 | August 29, 2021 | University of the Philippines Diliman | Falcon 9 Block 5 |
| Maya-5 | June 5, 2023 | University of the Philippines Diliman | Falcon 9 Block 5 |
| Maya-6 | June 5, 2023 | University of the Philippines Diliman | Falcon 9 Block 5 |
| Mayak | July 14, 2017 | — | Soyuz-2.1a |
| Mayflower | December 8, 2010 | — | Falcon 9 |
| Mazaalai (satellite) | June 3, 2017 | — | Falcon 9 |
| MDS-1 | February 4, 2002 | — | H-IIA |
| MEASAT-1 | January 12, 1996 | MEASAT Satellite Systems | Ariane 44L |
| MEASAT-2 | November 13, 1996 | MEASAT Satellite Systems | Ariane 44L |
| MEASAT-3 | December 11, 2006 | MEASAT Satellite Systems | Proton-M |
| MEASAT-3a | June 21, 2009 | MEASAT Satellite Systems | Zenit-3SLB |
| MEASAT-3b | September 11, 2014 | MEASAT Satellite Systems | Ariane 5 ECA |
| MEASAT-3d | June 22, 2022 | MEASAT Satellite Systems | Ariane 5 ECA |
Megha-Tropiques | October 12, 2011 | Indian Space Research Organisation | Polar Satellite Launch Vehicle-CA |
| Megsat | September 26, 2000 | — | Dnepr |
| MegSat | April 28, 1999 | — | Kosmos-3M |
Mengtian experiment module | October 31, 2022 | China National Space Administration | Long March 5B |
Menut | January 3, 2023 | Institute of Space Studies of Catalonia | Falcon 9 Block 5 |
| Merah Putih 2 | February 20, 2024 | Telkomsat | Falcon 9 Block 5 |
Mercury Magnetospheric Orbiter | October 20, 2018 | Sagamihara Campus | Ariane 5 ECA |
Mercury Planetary Orbiter | October 20, 2018 | European Space Operations Centre | Ariane 5 ECA |
Mercury-Atlas 6 | February 20, 1962 | National Aeronautics and Space Administration | SM-65D Atlas |
Mercury-Atlas 7 | May 24, 1962 | National Aeronautics and Space Administration | SM-65D Atlas |
Mercury-Atlas 8 | October 3, 1962 | National Aeronautics and Space Administration | SM-65D Atlas |
Mercury-Atlas 9 | May 15, 1963 | National Aeronautics and Space Administration | SM-65D Atlas |
Mercury-Redstone 3 | May 5, 1961 | National Aeronautics and Space Administration | Mercury-Redstone Launch Vehicle |
Mercury-Redstone 4 | July 21, 1961 | National Aeronautics and Space Administration | Mercury-Redstone Launch Vehicle |
| Meridian 1 | December 24, 2006 | Russian Space Forces | Soyuz-2.1a |
| Meridian 2 | May 21, 2009 | Russian Space Forces | Soyuz-2.1a |
| Meridian 3 | November 2, 2010 | Russian Space Forces | Soyuz-2.1a |
| Meridian 4 | May 4, 2011 | Russian Space Forces | Soyuz-2.1a |
| Meridian 5 | December 23, 2011 | — | Soyuz-2.1b |
| Meridian 6 | November 14, 2012 | — | Soyuz-2.1a |
| Meridian 7 | October 30, 2014 | — | Soyuz-2.1a |
| Meridian-M 10 | March 22, 2022 | — | Soyuz-2.1a |
| Meridian-M 11 | April 3, 2026 | — | Soyuz-2.1a |
| Meridian-M 8 | July 30, 2019 | — | Soyuz-2.1a |
| Meridian-M 9 | February 20, 2020 | — | Soyuz-2.1a |
| MEROPE | July 26, 2006 | — | Dnepr |
| MESAT1 | July 4, 2024 | — | — |
MESSENGER | August 3, 2004 | Applied Physics Laboratory, National Aeronautics and Space Administration | Delta II |
| Meteor 1-10 | December 29, 1971 | — | Vostok-2M |
| Meteor 1-2 | October 6, 1969 | — | Vostok-2M |
| Meteor 1-3 | March 17, 1970 | — | Vostok-2M |
Meteor-1 1 | March 26, 1969 | — | Vostok-2M |
Meteor-3M No.1 | December 10, 2001 | Roscosmos State Corporation | Zenit-2 |
Meteor-M No.1 | September 17, 2009 | Roscosmos State Corporation | Soyuz-2.1b |
Meteor-M No.2-1 | November 28, 2017 | — | Soyuz-2.1b |
Meteor-M No.2-1 | July 8, 2014 | — | Soyuz-2.1b |
| Meteor-M No.2-2 | July 5, 2019 | — | Soyuz-2.1b |
Meteoroid Technology Satellite | August 13, 1972 | National Aeronautics and Space Administration | Scout D-1 |
Meteosat 1 | November 23, 1977 | European Space Agency | Delta 2000 |
Meteosat 10 | July 5, 2012 | EUMETSAT | Ariane 5 ECA |
Meteosat 11 | July 15, 2015 | EUMETSAT | Ariane 5 ECA |
Meteosat 12 | December 13, 2022 | EUMETSAT | Ariane 5 ECA+ |
Meteosat 13 | July 1, 2025 | EUMETSAT | Falcon 9 Block 5 |
Meteosat 14 | August 27, 2026 | EUMETSAT | Ariane 62 |
Meteosat 2 | June 19, 1981 | European Space Agency | Ariane 1 |
Meteosat 3 | June 15, 1988 | European Space Agency | Ariane 44LP |
Meteosat 4 | March 6, 1989 | European Space Agency | Ariane 44LP |
Meteosat 5 | March 2, 1991 | EUMETSAT, European Space Agency | Ariane 44LP |
Meteosat 6 | November 20, 1993 | EUMETSAT, European Space Agency | Ariane 44LP |
Meteosat 7 | September 2, 1997 | EUMETSAT | Ariane 44LP |
Meteosat 8 | August 28, 2002 | EUMETSAT | Ariane 5G |
Meteosat 9 | December 21, 2005 | EUMETSAT | Ariane 5GS |
Methane Remote Sensing Lidar Mission | 2028 | German Aerospace Center, CNES | — |
| MethaneSAT | March 4, 2024 | Environmental Defense Fund | Falcon 9 Block 5 |
MetOp-A | October 19, 2006 | EUMETSAT | Soyuz-2.1a |
MetOp-B | September 17, 2012 | EUMETSAT | Soyuz-2.1a |
MetOp-C | November 7, 2018 | EUMETSAT | Soyuz-2.1b |
MetOp-SG-A1 | August 13, 2025 | EUMETSAT | Ariane 62 |
| MEV-1 | October 9, 2019 | SpaceLogistics | Proton-M |
| MEV-2 | August 15, 2020 | SpaceLogistics | Ariane 5 ECA+ |
| MEXSAT-1 | May 16, 2015 | Secretariat of Infrastructure, Communications and Transportation | Proton-M |
| MEXSAT-3 | December 19, 2012 | Secretariat of Infrastructure, Communications and Transportation | Ariane 5 ECA |
| MICE-1 | November 28, 2025 | — | Falcon 9 |
| Michibiki 1 | September 11, 2010 | National Space Policy Secretariat, Japan Aerospace Exploration Agency | H-IIA |
Michibiki 1R | October 26, 2021 | National Space Policy Secretariat | H-IIA |
Michibiki 2 | June 1, 2017 | National Space Policy Secretariat | H-IIA |
Michibiki 3 | August 19, 2017 | National Space Policy Secretariat | H-IIA |
Michibiki 4 | October 9, 2017 | National Space Policy Secretariat | H-IIA |
Michibiki 5 | December 22, 2025 | National Space Policy Secretariat | H3 Launch Vehicle |
Michibiki 6 | February 2, 2025 | National Space Policy Secretariat | H3 Launch Vehicle |
Michibiki 7 | August 10, 2026 | National Space Policy Secretariat | H3 Launch Vehicle |
MicroCarb | July 26, 2025 | CNES | Vega C |
| MicroDragon | January 18, 2019 | — | Epsilon |
| Microsat 1 | July 17, 1991 | Defense Advanced Research Projects Agency | Pegasus |
| Microsat 2 | July 17, 1991 | Defense Advanced Research Projects Agency | Pegasus |
| Microsat 3 | July 17, 1991 | Defense Advanced Research Projects Agency | Pegasus |
| Microsat 4 | July 17, 1991 | Defense Advanced Research Projects Agency | Pegasus |
| Microsat 5 | July 17, 1991 | Defense Advanced Research Projects Agency | Pegasus |
| Microsat 6 | July 17, 1991 | Defense Advanced Research Projects Agency | Pegasus |
| Microsat 7 | July 17, 1991 | Defense Advanced Research Projects Agency | Pegasus |
Microsat-1 | August 29, 1996 | Regional University of Cordoba IUA | Molniya-M |
Microsat-R | January 24, 2019 | Defence Research and Development Organisation | Polar Satellite Launch Vehicle-DL |
Microsat-TD | January 12, 2018 | Indian Space Research Organisation | Polar Satellite Launch Vehicle-XL |
| MicroSCOPE | April 25, 2016 | CNES | Soyuz-2.1a |
| Microvariability and Oscillations of Stars | June 30, 2003 | Canadian Space Agency, Microsat Systems Canada Inc. | Rokot |
MIDAS 1 | February 26, 1960 | United States Air Force | Atlas-Agena A |
| MIDAS 10 | June 9, 1966 | — | Atlas SLV-3 Agena-D |
| MIDAS 11 | August 19, 1966 | — | Atlas SLV-3 Agena-D |
| MIDAS 12 | October 5, 1966 | — | Atlas SLV-3 Agena-D |
MIDAS 2 | May 24, 1960 | United States Air Force | Atlas-Agena A |
| MIDAS 3 | July 12, 1961 | United States Air Force | Atlas-Agena B |
| MIDAS 4 | October 21, 1961 | United States Air Force | Atlas-Agena B |
| MIDAS 5 | April 9, 1962 | United States Air Force | Atlas-Agena B |
| MIDAS 7 | May 9, 1963 | United States Air Force | Atlas-Agena B |
| MIDAS 9 | July 19, 1963 | United States Air Force | Atlas-Agena B |
Midcourse Space Experiment | April 24, 1996 | — | Delta II |
MidSTAR-1 | March 9, 2007 | — | Atlas V 401 |
MightySat-1 | December 4, 1998 | Air Force Research Laboratory, Space Test Program | Space Shuttle |
MightySat-2.1 | July 19, 2000 | Space Test Program | Minotaur I |
Mikhailo Lomonosov | April 28, 2016 | Lomonosov Moscow State University | Soyuz-2.1a |
| Milani | October 7, 2024 | European Space Agency | Falcon 9 Block 5 |
| MILStar 1 | February 7, 1994 | — | Titan IV |
| MILStar 2 | November 6, 1995 | — | Titan IV |
| MILStar 3 | April 30, 1999 | — | Titan IV |
| MILStar 5 | January 16, 2002 | — | Titan IV |
| MILStar 6 | April 8, 2003 | — | Titan IV |
| MIMOSA | June 30, 2003 | — | Rokot |
| Minairó | April 15, 2023 | — | Falcon 9 Block 5 |
| Minerva II Rover-1A | December 3, 2014 | — | H-IIA |
| Minerva II Rover-1B | December 3, 2014 | — | H-IIA |
| Minerva II Rover-2 | December 3, 2014 | — | H-IIA |
Miniature X-ray Solar Spectrometer CubeSat (MinXSS) | December 6, 2015 | University of Colorado Boulder | Atlas V 401 |
| Minisat 01 | April 21, 1997 | Instituto Nacional de Técnica Aeroespacial Esteban Terradas | Pegasus |
| Minisatellite Italiano di Technologia Avanzata | July 15, 2000 | Italian Space Agency | Kosmos-3M |
Mir | February 19, 1986 | — | Proton-K |
| MIR-Sat 1 | June 3, 2021 | — | Falcon 9 |
| Miranda | March 9, 1974 | — | Scout D-1 |
| Mission Extension Pod-1 | July 21, 2026 | SpaceLogistics | Falcon 9 Block 5 |
| Mission Extension Pod-2 | July 21, 2026 | SpaceLogistics | Falcon 9 Block 5 |
| Mission Extension Pod-3 | July 21, 2026 | SpaceLogistics | Falcon 9 Block 5 |
Mission Robotic Vehicle-1 | July 21, 2026 | SpaceLogistics | Falcon 9 Block 5 |
| Misty 1 | February 28, 1990 | National Reconnaissance Office | Space Shuttle |
| Misty 2 | May 22, 1999 | National Reconnaissance Office | Titan IV |
| Mitsuba | October 12, 2022 | — | Epsilon |
| MK-1TS | December 24, 2004 | — | Tsyklon-3 |
| MKA PN2 | July 8, 2014 | — | Soyuz-2.1b |
| MKA-FKI 1 | July 22, 2012 | — | Soyuz-FG |
| Mobile Broadcasting Satellite | March 13, 2004 | Agility Beyond Space | Atlas IIIA |
| Mohammed VI - A | November 8, 2017 | Royal Centre for Remote Sensing | Vega |
Mohammed VI - B | November 21, 2018 | Royal Centre for Remote Sensing | Vega |
| Molniya 1- 1 | April 23, 1965 | — | Molniya |
| Molniya 1- 2 | October 14, 1965 | — | Molniya |
| Molniya 1-11 | April 11, 1969 | — | Molniya-M |
Molniya 1-3 | April 25, 1966 | — | Molniya |
| Molniya 1-88 | December 14, 1994 | — | — |
| Molniya-1 No.2 | June 4, 1964 | — | Molniya |
| Monitor-E | August 26, 2005 | — | Rokot |
| Mono-Nikko | April 23, 2026 | Di-Nikko Engineering | Electron |
Moon Impact Probe | October 22, 2008 | Indian Space Research Organisation | Polar Satellite Launch Vehicle |
Morelos 1 | June 17, 1985 | — | Space Shuttle |
Morelos 2 | November 27, 1985 | — | Space Shuttle |
| Morelos 3 | October 2, 2015 | Secretariat of Infrastructure, Communications and Transportation | Atlas V 421 |
| MOS-1 | February 19, 1987 | National Space Development Agency | N-II |
| MOS-1b | February 7, 1990 | — | H-I |
| MOVE-II | December 3, 2018 | — | Falcon 9 |
| MOVE-II | December 3, 2018 | Technical University of Munich | Falcon 9 Block 5 |
| Mozhayets-5 | October 27, 2005 | — | Kosmos-3M |
| Mołnia 1-4 | October 20, 1966 | — | Molniya |
| MRC-100 | June 12, 2023 | — | Falcon 9 Block 5 |
| MSAT 1 | April 20, 1996 | — | Ariane 42P |
MSTI-1 | November 21, 1992 | Ballistic Missile Defense Organization | Scout G-1 |
MSTI-2 | May 9, 1994 | United States Air Force | Scout G-1 |
| MSTI-3 | May 17, 1996 | Space Systems Command | Pegasus-H |
MTCUBE | July 5, 2019 | — | Soyuz-2.1b |
MTSat-1 | November 15, 1999 | Ministry of Land, Infrastructure, Transport and Tourism | H-II |
MTSat-1R | February 26, 2005 | Japan Meteorological Agency, Japan Civil Aviation Bureau | H-IIA |
| MTSat-2 | February 18, 2006 | Japan Civil Aviation Bureau, Japan Meteorological Agency | H-IIA |
MUBLCOM | May 18, 1999 | United States Army Communications-Electronics Command | Pegasus-XL |
| Multi Research Payload Vehicle | September 2, 1965 | United States Air Force | Thor-Agena D |
| Multi-Application Survivable Tether | April 17, 2007 | — | Dnepr |
| Multispectral Thermal Imager | March 12, 2000 | National Nuclear Security Administration, Space Test Program | Minotaur-C |
| Munin | November 21, 2000 | — | Delta II |
MUOS 1 | February 24, 2012 | — | Atlas V 551 |
| MUOS 2 | July 19, 2013 | — | Atlas V 551 |
MUOS 3 | January 21, 2015 | — | Atlas V 551 |
| MUOS 4 | September 2, 2015 | — | Atlas V 551 |
MUOS 5 | June 24, 2016 | — | Atlas V 551 |
| Musket Ball | August 7, 1971 | — | Atlas E/F |
| Myojo | February 3, 1994 | National Space Development Agency | H-II |
| Máni | 2029 | University of Copenhagen | — |