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Astronomy Object archive with linked event snippets and related articles.

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March 21 in Universe History: Space Missions, Satellites and Exploration

March 21, 2026
1963 On 21 March 1963, transmitters aboard the Soviet Mars 1 probe fell silent. The final radio contact occurred when the craft was about 106 million km from Earth, ending communications during cruise and leaving it to proceed toward its planned Mars flyby without further telemetry, after earlier relays had returned measurements of interplanetary conditions between Earth and Mars.
2001 On 21 March 2001, Space Shuttle Discovery landed at Kennedy after STS-102, completing the first Expedition crew rotation for the International Space Station and returning Expedition 1 to Earth. The mission also delivered and later returned the Leonardo multipurpose logistics module with supplies and racks, advancing early station assembly, joint operations, and orbital logistics procedures.
2020 On 21 March 2020, Arianespace and Starsem successfully delivered 34 OneWeb satellites to low Earth orbit on Soyuz Flight ST28, advancing deployment of the broadband constellation. The launch increased the number of spacecraft available for global connectivity services and continued the program’s early launch cadence.
2024 On 21 March 2024, SpaceX CRS-30 lifted off carrying NASA’s BurstCube CubeSat. After later release from the International Space Station, BurstCube was designed to detect and localize short gamma-ray bursts and send rapid alerts to Earth, enabling follow-up by other observatories and multimessenger campaigns focused on neutron-star mergers.
All names in this article
Alphonsus Arianespace ASI AsiaSat 3S Atlas-Agena AVUM Baikonur BOLT-2 BurstCube Cape Canaveral Cassini CRS-30 Dragon Drew Feustel Europe’s Spaceport Expedition 1 Expedition 55 Expedition 56 Falcon 9 French Guiana High Energy Solar Spectroscopic Imager Imaging Science Subsystem Ingenuity International Launch Services JPL Kennedy L4 Lagrange point Leonardo Marina Vasilevskaya Mars 1 MDIS Mercury MESSENGER Mid-Atlantic Regional Spaceport NASA Planetary Data System National Reconnaissance Office NROL-123 Oleg Artemyev Oleg Novitskiy OneWeb PDS4 Standards Reference Perseverance PRISMA Proton Ranger 9 Ricky Arnold Rocket Lab Electron Saturn Soyuz Flight ST28 Soyuz MS-08 SpaceX SPICE Starsem Terrier-Improved Malemute Titan Tracy Dyson Vega Wallops Wallops Island Asia Europe Russia Air Force Research Laboratory Io Mars Moon Sun International Space Station Space Shuttle Discovery STS-102

March 20 in Universe History: Space Missions, Astronomy and Exploration

March 20, 2026
2015 On March 20, 2015, a total solar eclipse occurred as the Moon’s umbra skimmed Earth at a glancing angle on the March equinox. Totality passed south of Greenland to near the North Pole, crossing the Faroe Islands and Svalbard, while a broad partial eclipse was visible across Europe and beyond.
2024 On March 20, 2024, China launched the Queqiao-2 relay satellite on a Long March-8 rocket from the Wenchang Space Launch Site to provide Earth–Moon communications services, a key step for near-term far-side sample-return operations and longer-term south polar exploration in the Chinese lunar program.

March 20 Major Events in World History

March 20, 2026
1861 A magnitude-6.8 earthquake on 20 March 1861 destroys much of Mendoza, Argentina, killing thousands and reshaping the city; it remains one of Argentina’s deadliest quakes.