Vostok 2, was a Soviet space mission which carried cosmonaut Gherman Titov into orbit for a full day on which date, Titov's number of orbits and flight time would be surpassed, until by American astronaut Gordon Cooper's Mercury-Atlas 9 spaceflight in May 1963?
August 6, 1961
Vostok 2
Vostok 2 (Russian: Восток-2 , "Orient 2" or "East 2") was a Soviet space mission which carried cosmonaut Gherman Titov into orbit for a full day on August 6, 1961 to study the effects of a more prolonged period of weightlessness on the human body.
 Titov orbited the Earth over 17 times, exceeding the single orbit of Yuri Gagarin on Vostok 1 − as well as the suborbital spaceflights of American astronauts Alan Shepard and Gus Grissom aboard their respective Mercury-Redstone 3 and 4 missions.
 Indeed, Titov's number of orbits and flight time would not be surpassed by an American astronaut until Gordon Cooper's Mercury-Atlas 9 spaceflight in May 1963.
Gordon Cooper
Leroy Gordon "Gordo" Cooper Jr. (March 6, 1927 – October 4, 2004), (Col, USAF), better known as Gordon Cooper, was an American aerospace engineer, test pilot, United States Air Force pilot, and one of the seven original astronauts in Project Mercury, the first manned space program of the United States.
Mercury-Atlas 9
Mercury-Atlas 9 was the final manned space mission of the U.S. Mercury program, launched on May 15, 1963 from Launch Complex 14 at Cape Canaveral, Florida.
 The spacecraft, named Faith 7, completed 22 Earth orbits before splashing down in the Pacific Ocean, piloted by astronaut Gordon Cooper, then an Air Force major.
 The Atlas rocket was No. 130-D, and the Mercury spacecraft was No. 20.
 This mission marks the last time an American was launched alone to conduct an entirely solo orbital mission. Gherman Titov
Gherman Stepanovich Titov (Russian: Герман Степанович Титов ; 11 September 1935 – 20 September 2000) was a Soviet cosmonaut who, on 6 August 1961, became the second human to orbit the Earth, aboard Vostok 2, preceded by Yuri Gagarin on Vostok 1.
 He was the fourth person in space, counting suborbital voyages of US astronauts Alan Shepard and Gus Grissom. Mercury-Atlas 10
Mercury-Atlas 10 (MA-10) was a cancelled early manned space mission, which would have been the last flight in NASA's Mercury program.
 It was planned as a three-day extended mission, to launch in late 1963; the spacecraft, Freedom 7-II, would have been flown by Alan Shepard, a veteran of the suborbital Mercury-Redstone 3 mission in 1961.
 However, it was cancelled after the success of the one-day Mercury-Atlas 9 mission in May 1963, to allow NASA to focus its efforts on the more advanced two-man Gemini program. Titov (crater)
Titov is a relatively small lunar impact crater on the far side of the Moon.
 The most unusual aspect of this crater is that it is located entirely within the Mare Moscoviense, one of the few maria found on the far side of the Moon.
 It lies to the northwest of the crater Komarov, in the northern half of the mare.
 It is named for cosmonaut Gherman Titov, the second person to orbit the Earth. Soyuz TM-4
Soyuz TM-4 was the fourth manned spacecraft to dock with the space station Mir.
 It was launched in December 1987, and carried the first two crew members of the third long duration expedition, Mir EO-3.
 These crew members, Vladimir Titov and Musa Manarov, would stay in space for just under 366 days, setting a new spaceflight record.
 The third astronaut launched by Soyuz TM-4 was Anatoli Levchenko, who returned to Earth about a week later with the remaining crew of Mir EO-2.
 Levchenko was a prospective pilot for the Soviet Space shuttle "Buran".
 The purpose of his mission, named Mir LII-1, was to familiarize him with spaceflight. Titov Main Test and Space Systems Control Centre
The Titov Main Test and Space Systems Control Centre (Russian: Главный испытательный центр испытаний и управления космическими средствами (ГИЦИУ КС) , "Glavny Ispytatelny Tsentr Ispytany i Upravleniya Kosmicheskimi Sredstvami (GITSIU COP)" ) (also referenced as the Titov Space Control Centre and Titov Space Centre) is the main Russian military and commercial satellite control centre.
 It is run by the Russian Space Forces.
 Located roughly 40 km southwest of Moscow in the formerly closed town of Krasnoznamensk, the centre was built in 1957 as part of the Soviet space program, and was known by the name of Golitsyno-2. Mercury-Atlas 8
Mercury-Atlas 8 (MA-8) was the fifth United States manned space mission, part of NASA's Mercury program.
 Astronaut Walter M. Schirra Jr., orbited the Earth six times in the Sigma 7 spacecraft on October 3, 1962, in a nine-hour flight focused mainly on technical evaluation rather than on scientific experimentation.
 This was the longest U.S. manned orbital flight yet achieved in the Space Race, though well behind the several-day record set by the Soviet Vostok 3 earlier in the year.
 It confirmed the Mercury spacecraft's durability ahead of the one-day Mercury-Atlas 9 mission that followed in 1963. Soviet space program
The Soviet space program (Russian: Космическая программа СССР, "Kosmicheskaya programma SSSR") comprised the rocketry and space exploration programs conducted by the former Soviet Union (USSR) from the 1930s until its dissolution in 1991.
 Over its sixty-year history, this primarily classified military program was responsible for a number of pioneering accomplishments in space flight, including the first intercontinental ballistic missile (R-7), first satellite (Sputnik 1), first animal in Earth orbit (the dog Laika on Sputnik 2), first human in space and Earth orbit (cosmonaut Yuri Gagarin on Vostok 1), first woman in space and Earth orbit (cosmonaut Valentina Tereshkova on Vostok 6), first spacewalk (cosmonaut Alexey Leonov on Voskhod 2), first Moon impact ("Luna 2"), first image of the far side of the moon ("Luna 3") and unmanned lunar soft landing ("Luna 9"), first space rover ("Lunokhod 1"), first sample of lunar soil automatically extracted and brought to Earth ("Luna 16"), and first space station (Salyut 1).
 Further notable records included the first interplanetary probes: Venera 1 and Mars 1 to fly by Venus and Mars, respectively, Venera 3 and Mars 2 to impact the respective planet surface, and Venera 7 and Mars 3 to make soft landings on these planets.