|Mission type||Mir expedition|
|Mission duration||193.8 days (Onufrienko, Usachyov) (launch to landing)|
|Began||21 February 1996|
|Ended||2 September 1996|
|Arrived aboard||Soyuz TM-23
Space Shuttle Atlantis
|Departed aboard||Soyuz TM-23
Space Shuttle Atlantis
|Crew size||2 (February-March)
Shannon Lucid* (from March)
* - Transferred to EO-22
Mir EO-21 was a long-duration mission aboard the Russian Space station Mir, which occurred between February and September 1996. The crew consisted of two Russian cosmonauts, Commander Yuri Onufrienko and Yury Usachov, as well as American astronaut Shannon Lucid. Lucid arrived at the station about a month into the expedition, and left about a week following its conclusion; NASA refers to her mission as NASA-2. She was the second American to have a long-duration stay aboard Mir, the first being Norman Thagard, as a crew member of Mir EO-18; he stayed on the station for 111 days. Some sources refer to her mission as Mir NASA-1, claiming that she was the first American to have a long-duration stay aboard Mir.
|Commander||Yuri Onufrienko||First||21 February 1996
|2 September 1996
|Flight Engineer||Yury Usachov||Second|
|Flight Engineer||Shannon Lucid||Fifth||22 March 1996
|26 September 1996
|188 days||Aboard the station
for some of Mir EO-22
Crew handover and Mir Cassiopee
On 19 August 1996, the Soyuz TM-24 spacecraft docked with Mir's front port. It brought to the station two of the next long-duration crew, Valery Korzun and Aleksandr Kaleri. The following expedition, Mir EO-22, would be commanded by Korzun. Also aboard Soyuz TM-24 was French astronaut Claudie Haigneré (then called Claudie Andre-Deshays), who's mission is known as Mir Cassiopee.
- "Mir EO-21". Encyclopedia Astronautica. Retrieved 11 December 2010.
- "STS-76". Encyclopedia Astronautica. Retrieved 11 December 2010.
- "STS-79". Encyclopedia Astronautica. Retrieved 11 December 2010.
- "NASA-2". NASA.
- Marsha Freeman (July 2000). Challenges of human space exploration. Springer. p. 260. ISBN 1-85233-201-8.
- "Mir NASA-1". Encyclopedia Astronautica.
- "Mir Cassiopee". Encyclopedia Astronautica.
- "International cooperation in space manned programs realization". Yuri Gagarin Cosmonauts Training Center. Retrieved 11 December 2010.