Gemini 10 Lapel Pin
Gemini 10 was the eighth crewed Earth-orbiting spacecraft of the Gemini series, carrying astronauts John Young and Michael Collins. Its primary purpose was to conduct rendezvous and docking tests with the Agena target vehicle. The mission plan included a rendezvous with the Gemini 8 Agena target, two extravehicular activity (EVA) excursions, and the performance of 15 scientific, technological, and medical experiments. The scientific experiments were related to (1) zodiacal light, synoptic terrain, and synoptic weather photography, (2) micrometeorite collections, (3) UV astronomical camera, (4) ion wake measurements, and (5) meteoroid erosion.
Gemini 10 was launched on 18 July from Complex 19 at 5:20:26 p.m. EST (22:20:26.648 UT) and inserted into a 159.9 x 268.9 km orbit. At orbit insertion Gemini 10 was about 1600 km behind the Gemini Agena Target Vehicle 10 (GATV-10) which had been launched into a near circular orbit about 100 minutes earlier. Rendezvous with GATV-10 was achieved on the 4th revolution at 10:43 p.m. and at 11:13:03 p.m. docking was achieved. A large out-of-plane error in the initial orbit required the Gemini to use 60% of its fuel for the rendezvous, over twice the planned amount. As a result most of the mission plan was revised. To conserve fuel, Gemini 10 remained docked to GATV-10 for the next 39 hours and used the GATV propulsion system for maneuvers. The planned docking practice runs were cancelled.