Launches
ON RECORD16MISSIONS
15 of them succeeded. The earliest was in 1961 and the latest in 2026.
ARCHIVE // DAY OF YEAR
April 21 in spaceflight
16 launches flew on April 21, the earliest of them in 1961, and 15 of them succeeded. Wikipedia lists 2 spaceflight and astronomy events on April 21. Pick another date to see what happened on it.
Recorded events
IN THE RECORD2ENTRIES
Spaceflight and astronomy entries from Wikipedia for this date, oldest first, starting in 1964.
Pictures from this date
NONE0IMAGES
There's no Astronomy Picture of the Day we can show for this date.
What happened on April 21
1964
A Transit-5bn satellite fails to reach orbit after launch; as it re-enters the atmosphere, 2.1 pounds (0.95 kg) of radioactive plutonium in its SNAP RTG power source is widely dispersed.
Transit (satellite navigation system) ↗1972
Astronauts John Young and Charles Duke fly Apollo 16's Apollo Lunar Module to the Moon's surface, the fifth NASA Apollo Program crewed lunar landing.
John Young (astronaut) ↗
Launches on April 21Archive read 2026-11-05. Anything after that isn't listed here.
16 launches
ONLINE
- 2026Falcon 9 Block 5 | GPS III SV10SpXSUCCESS
- 2025Falcon 9 Block 5 | Dragon CRS-2 SpX-32SpXSUCCESS
- 2022Falcon 9 Block 5 | Starlink Group 4-14SpXSUCCESS
- 2013Antares 110 | Cygnus Mass SimulatorOSCSUCCESS
- 1999Dnepr | UOSAT-OSCAR-36ISCKSUCCESS
- 1997Pegasus XL | Minisat & Celestis Space Burial #1OSCSUCCESS
- 1995Ariane 40 | ERS-2ASASUCCESS
- 1993Molniya-M | Molniya-3 57LPRSCSUCCESS
- 1987Soyuz-U2 | Progress 29CCCPSUCCESS
- 1982Soyuz U | Zenit-6U 56CCCPSUCCESS
- 1982Kosmos-3M | Taifun-2 12CCCPSUCCESS
- 1981Tsiklon-2 | US-A 18CCCPSUCCESS
- 1972Kosmos 11K63 | DS-P1-Yu 53CCCPSUCCESS
- 1968Molniya-M | Molniya-1 8CCCPSUCCESS
- 1964Thor DM-21 Ablestar | Transit-5BN 3USAFFAILURE
- 1961Trailblazer 1 | Trailblazer 1gNASASUCCESS
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- VIEW
LISTING
Cosmos, by Carl Sagan
Sagan's tour of the universe and how we came to understand it. It keeps the science in.
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LISTING
Pale Blue Dot, by Carl Sagan
Sagan's case for people leaving Earth one day, and an honest look at how hard that would be.
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LISTING
Project Hail Mary, by Andy Weir
A science-fiction novel from the author of The Martian, built around solving one engineering problem after another.
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Sources and licences
Event text and thumbnails come from Wikipedia and are used under CC BY-SA 4.0. Images come only from Wikimedia Commons, which doesn't accept non-free content. Each thumbnail links to its file page, which lists its licence and author.
Launch records are from The Space Devs’ Launch Library 2. Pictures are NASA’s Astronomy Picture of the Day. Many of them belong to the photographer or a partner agency, so we only show the ones credited to NASA alone.