Gemini 6A and Gemini 7 (1965): The First Space Rendezvous

The rendezvous of Gemini 6A and Gemini 7 on 15 December 1965 was the first time two crewed spacecraft deliberately met in orbit. Flying about 300 kilometres above the Earth, the two American capsules came within roughly 30 centimetres of each other and flew in formation for hours. The mission proved that spacecraft could find and approach each other, a technique on which the Apollo Moon landings depended.

Why rendezvous mattered

NASA’s plan for reaching the Moon, chosen in 1962, was lunar orbit rendezvous. A lunar module would land on the Moon, then lift off and meet the command module waiting in lunar orbit. If the two craft could not find each other, the astronauts would be stranded. Project Gemini, flown between Mercury and Apollo, was designed to practise this and other skills, including long-duration flight and spacewalks.

Rendezvous is harder than it sounds. In orbit, firing an engine to speed up raises a spacecraft into a higher orbit, where it actually travels more slowly around the Earth. Pilots had to learn to use orbital mechanics, radar and onboard computers rather than simply steering towards their target.

Earlier Soviet “group flights”, such as Vostok 5 and Vostok 6 in 1963, had placed two capsules in nearby orbits, but they could not change orbit and passed several kilometres apart. Gemini spacecraft had thrusters that allowed true manoeuvring.

A mission rescued from failure

The original Gemini 6, crewed by Walter “Wally” Schirra and Thomas Stafford, was to rendezvous and dock with an uncrewed Agena target rocket. On 25 October 1965 the Agena exploded minutes after launch, and the crewed launch was cancelled.

Engineers proposed a bold alternative: use Gemini 7, already scheduled as a 14-day endurance flight, as the target. Gemini 7, with Frank Borman and Jim Lovell aboard, was launched on 4 December 1965. The renamed Gemini 6A was meant to follow eight days later.

On 12 December the Titan II rocket’s engines ignited and then shut down after about a second, when an electrical plug fell out too early. By the rules, Schirra could have pulled the ejection handle, but he judged that the rocket had not left the pad and stayed put, saving the spacecraft and the mission. Technicians later also found a plastic dust cover left in an engine component.

The rendezvous

Gemini 6A finally lifted off from Cape Kennedy on 15 December 1965. Over its first four orbits Schirra fired a series of manoeuvres guided by radar and the onboard computer, gradually catching up with Gemini 7. Less than six hours after launch the two spacecraft were flying side by side.

For roughly five hours the crews flew in formation, taking turns to manoeuvre around each other at distances from about 30 centimetres to around 90 metres. They could see each other’s faces through the windows, and Schirra and Stafford, both graduates of the US Naval Academy, held up a sign reading “Beat Army” for Borman, a West Point graduate. The astronauts took many photographs, including the image of Gemini 7 above the Earth used to illustrate this article.

Jingle Bells in orbit

On 16 December, before re-entry, Stafford reported an unidentified object in a polar orbit with a pilot in a red suit, an obvious joke about Santa Claus. Schirra then played “Jingle Bells” on a small harmonica while Stafford rang a set of bells. The harmonica and bells, now in the Smithsonian, are often described as the first musical instruments played in space.

Gemini 6A splashed down in the Atlantic later that day after just over 25 hours in flight. Gemini 7 stayed up until 18 December, completing nearly 14 days, a record that showed humans could survive as long as a trip to the Moon and back would require.

Consequences

Gemini 6A showed that the rendezvous technique worked. The next step came on 16 March 1966, when Neil Armstrong and David Scott on Gemini 8 made the first docking in space with an Agena target. Later Gemini flights practised different rendezvous methods, and in 1969 the lunar module and command module of Apollo 11 met successfully in lunar orbit after the first Moon landing.

Timeline

• 1965, 25 October: The Agena target explodes and the first Gemini 6 launch is cancelled.
• 1965, 4 December: Gemini 7 is launched with Borman and Lovell.
• 1965, 12 December: Gemini 6A’s engines shut down on the pad; the crew does not eject.
• 1965, 15 December: Gemini 6A is launched and completes the first crewed rendezvous.
• 1965, 16 December: Gemini 6A splashes down after the “Jingle Bells” broadcast.
• 1965, 18 December: Gemini 7 returns after nearly 14 days in space.
• 1966, 16 March: Gemini 8 makes the first docking in orbit.

Why it matters

The meeting of Gemini 6A and Gemini 7 turned a theory of orbital mechanics into a proven skill. Every later docking, from Apollo to the space stations of today, builds on the techniques first demonstrated in December 1965.