Put these Project Mercury flights in order by launch date, earliest first.

The story behind it

Mercury flew before NASA had qualified any watch; formal chronograph testing only began in 1964. Schirra's CK2998 on Sigma 7 (October 1962) came from his own collection and was the first Omega in space. The Speedmaster's first flight as a NASA-qualified instrument was Gemini 3 on 23 March 1965, when Grissom and Young wore the ST 105.003. The Moonwatch's space record therefore starts two and a half years before NASA chose it.