After the successful launch of Vostok 5 on 14 June, Tereshkova began final preparations for her own flight. On the morning of 16 June 1963, Tereshkova and her backup Solovyova were both dressed in spacesuits and taken to the launch pad by bus. Following the tradition set by Gagarin, Tereshkova also urinated on the bus tire, becoming the first woman to do so. After completing her communication and life support checks, she was sealed inside the Vostok. After a two-hour countdown, Vostok 6 launched faultlessly, and Tereshkova became the first woman in space; she remains the only woman to fly to space solo, and the youngest at 26 years of age. Her call sign in this flight was "Chaika" (), later commemorated as the name of an asteroid, 1671 Chaika. After her launch, she radioed down: