Human Spaceflights

International Flight No. 20

Gemini 10


hi res version (174 KB)

hi res version (1,00 MB)

Launch, orbit and landing data

Launch date:  18.07.1966
Launch time:  22:20 UTC
Launch site:  Cape Canaveral
Launch pad:  LC-19
Altitude:  159,9 - 764 km
Inclination:  28.85°
Landing date:  21.07.1966
Landing time:  21:07 UTC
Landing site:  26° 44,7' N, 71° 57' W

walkout photo

hi res version (553 KB)

alternate crew photo

alternate crew photo


No.   Surname Given names Position Flight No. Duration Orbits
1  Young  John Watts  Command Pilot 2 2d 22h 46m  43 
2  Collins  Michael  PLT 1 2d 22h 46m  43 

Crew seating arrangement

1  Young
2  Collins

Backup Crew

No.   Surname Given names Position
1  Bean  Alan LaVern  Command Pilot
2  Williams  Clifton Curtis "CC"  PLT

hi res version (424 KB)


Launch from Cape Canaveral; landing 850 km east of Florida in the Atlantic Ocean.

The main objectives of this mission were to dock with the Agena target vehicle GATV-10 and to dock with the Agena Target Vehicle from the Gemini 8 mission (GATV-8). After docking with GATV-10 in low orbit, John Young and Michael Collins should use it to climb to a high orbit to meet with the dead, drifting Agena left over from the aborted Gemini 8 flight - thus executing the program's first double rendezvous. With no electricity on board the second Agena the rendezvous was accomplished with eyes only - no radar. In addition Michael Collins was scheduled to perform a spacewalk. The mission patch was drawn by Barbara Young (John Young's wife at the time).

The docking with the unmanned Agena target vehicle GATV-10 was successful, even it was need more fuel than planned. Michael Collins learned that he was unable to use the sextant for navigation as it did not seem to work as expected. At first he mistook airglow as the real horizon when trying to make some fixes on stars. Then the image didn't seem right. He tried another instrument that they had on board but this was not practical to use as it had a very small field of view. They fortunately had a backup in the form of the computers on the ground. To save fuel, planned more docking and redocking maneuvers were not performed. During the docking the GATV-10 primary propulsion system was used to raise the dual spacecraft apogee to 764 km (a new record). The first burn of the Agena engine they made was 80 seconds long and put them in a 294 by 764 kilometers orbit. This was the highest a person had ever been (until the next mission when Gemini 11 went to over 1,000 kilometers (620 mi)). This burn was quite a ride for the crew. Because the Gemini and Agena docked nose to nose, the forces experienced were "eyeballs out" as opposed to "eyeballs in" for a launch from Earth.

Two EVAs were performed by Michael Collins. The first was a standup-EVA on July 19, 1966 (0h 38m) and Michael Collins began photographing stellar UV radiation around the Southern Milky Way.

After more 44 hours the Gemini spacecraft separated from the GATV-10. The Gemini used its own thrusters to complete the second rendezvous some three hours later with the GATV-8 target vehicle. After a couple more correction burns they were station keeping 3 meters away from the Agena.

Then the second EVA on July 20, 1966 (0h 49m) was performed by Michael Collins. First he retrieved a micro meteorite experiment mounted on the Gemini 10 spacecraft, but he lost it, when it floated out of the cabin during the EVA. He then walked from the Gemini spacecraft to the Agena target vehicle to retrieve the second micrometeorite package left in space all those months. While doing this he lost grip in space walk from Gemini to Agena, tumbled head over heels at end of umbilical around Gemini. Michael Collins needed a second attempt using the hand-held gun to turn back to the Agena, save the package and retrieved it. Returning into the capsule was difficult, because Michael Collins had gotten himself tangled in the umbilical. During this EVA he lost his camera.

There were 10 other experiments that the crew performed during the mission. Three were interested in radiation. MSC-3 was the Tri-Axis Magnetometer which measured levels in the South Atlantic Anomaly. There was also MSC-6, a beta spectrometer, measured potential radiation doses for Apollo missions, and MSC-7, a bremsstrahlung spectrometer which detected radiation flux as a function of energy when the spacecraft passed through the South Atlantic Anomaly. More experiments were about the Zodiacal light, about the ion and electron wake of the spacecraft and a navigation experiment.

The reentry was performed without any problems. Gemini 10 landed only 5.6 kilometers away from the intended landing site. The recovery ship was the USS Guadalcanal.

Photos / Drawings


Last update on November 29, 2014.