Soyuz TM-23

Launch & orbit data: Designation  23798 / 96011A Launch date - time  21 Feb 1996 - 12:34:05 UT Launch site  Baikonur, LC1 Launch vehicle  Soyuz 11A511U(# 651) OKB name - S/Nº  Soyuz 7K-STM (11F732) s/nº 72 Mass (kg)  7.150 Flight Crew  Onufriyenko, Yuri (CDR) Usachyov, Yuri (FE) Call Sign  Skif-1 & Skif-2 (Roman-age tribe) Earth orbit on :    - Perigee / Apogee  375 / 390 km    - Inclination  51.7°    - Period  92.2 min

Docking & landing data: Docking date - time  23 Feb 1996 - 14:20:35 UT Target spacecraft/port  Mir/Kvant Undocking date - time  02 Sep 1996 - 04:20:00 UT Deorbit burn date - time  02 Sep 1996 - 06:47:20 UT Landing date - time  02 Sep 1996 - 07:41:40 UT Landing location  107 km SW of Arkalyk (50° 17' N, 70° 50' E) Flight Duration (d:hr:min)  194:19:08 Nbr orbits   Landing crew  Onufrienko, Usachev, André-Deshays  (crew TM-23 & TM-24)

Launch Crew (EO-21):

Backup Crew

Mir over New Zealand - Credit: NASA.

French Cassiopeiae Mission Logo - Credit: NASA.

Mission details:

• Launch of the EO-21 crew, Yuri Ivanovich Onufrienko and Yuri Vladimirovich Usachyov (callsign Skif-1 and Skif-2) took place on Feb 21, 1996. At 1300 UTC Soyuz TM-23 was in a 200 x 233 km x 51.6 deg orbit.
• Soyuz TM-23 docked with Mir at 14:20:35 on Feb 23. The new crew of Yuriy Onufrienko and Yuriy Usachyov are working aboard the station. The Mir complex is in a 390 x 398 km x 51.6 deg orbit.
• both cosmonauts performed six EVA′s on 15.03.1996 (5h 51m), 20.05.1996 (5h 20m), 24.05.1996 (5h 43m), 30.05.1996 (4h 20m), 06.06.1996 (3h 34m) and 13.06.1996 (5h 42m) carrying out following work: installation of the telescopic boom, the MSCA solar array, the multi-spectral scanner, exchanging materials samples and deploying of a radar antenna; protein crystal growth experiments; more experiments in materials science using high temperture melting oven "Optizon"; module "Priroda" arrived on 26.04.1996; supplies arrived with cargo spacecraft Progress M-31; crew was visited by crew of STS-76; since that time (24.03.1996) U.S. astronaut Shannon Lucid completed resident crew.
• Soyuz TM-23 undocked from Mir on September 02 at 04:20 GMT, and made a small seperation burn at 04:24:40 GMT. Deorbit was at 06:47:20 GMT . The three modules separated at 07:14:36 and the parachute deployed at 07:26 GMT. The landing was at 07:41:40 GMT, 100 km SW of Akmola in Kazakstan with Yuri Onufrienko, Yuriy Usachyov and Claudie Andre-Deshays. This concluded the French ′Cassiopee′ mission.

Astrophilately covers:

Launch cancel Baikonur and special mission cancel, send registrated and signed by the crew. Special Kazakstan stamps instead of Russian.

Cosmic Mail: Cover with new red Mir boardcancel, docking date boardcancel: 230296 and undocking date boardcancel: 020996, signed by the complete crew TM-23 and STS-76.