Omega Speedmaster — Chronograph Wristwatch

The Omega Speedmaster is a family of chronograph wristwatches produced by the Swiss watchmaker Omega SA. Introduced in 1957 as a sports and racing timer, the model expanded upon Omega's earlier twentieth-century chronographs, complementing the company's role as official timekeeper for the Olympic Games. While the broader line includes automatic mechanical and analogue-digital variants, the manual-winding Speedmaster Professional—frequently termed the Moonwatch—became its most renowned model following its adoption by NASA for crewed space exploration.

Early operational space use began unofficially in October 1962, when astronaut Walter Schirra wore his personal reference CK 2998 aboard the Mercury-Atlas 8 mission. Following comprehensive NASA qualification testing across extreme temperatures, vacuum cycling, humidity, vibration, and acceleration, the Speedmaster was formally selected for spaceflight in March 1965. It saw official crewed deployment with Gus Grissom and John Young on Gemini 3, accompanied Ed White during the first American spacewalk on Gemini 4 mounted to his spacesuit sleeve on a long nylon Velcro strap, and became the first watch worn on the Moon during the Apollo 11 mission.

Classic iterations of the Speedmaster feature stainless-steel cases, black dials, domed Hésalite Plexiglas crystals, and a twelve-hour, triple-register chronograph layout. The inaugural 1957 model, reference CK 2915, introduced broad arrow hands and an external brushed stainless-steel tachymeter bezel powered by the manual-winding Calibre 321. Subsequent evolutions adopted black aluminium bezels, alpha and later baton hands, and an asymmetrical case designed to shield the pushers and crown on reference ST 105.012, which also introduced the Professional designation. In 1968 and 1969, Omega transitioned the series from Calibre 321 to Calibre 861.