First human spaceflight in history
Vostok 1 (, lit. 'East' or 'Orient') was the first spaceflight of the Vostok programme and the first human orbital spaceflight in history. The Vostok 3KA space capsule was launched from Baikonur Cosmodrome on 12 April 1961, with Soviet cosmonaut Yuri Gagarin aboard, making him the first human to reach orbital velocity around the Earth and to complete a full orbit around the Earth.
The orbital spaceflight consisted of a single orbit around Earth which skimmed the upper atmosphere at at its lowest point. The flight took 108 minutes from launch to landing. Gagarin parachuted to the ground separately from his capsule after ejecting at altitude.
Background.
The Space Race between the Soviet Union and the United States, the two Cold War superpowers, began just before the Soviet Union launched the world's first artificial satellite, Sputnik 1, in 1957. Both countries wanted to develop spaceflight technology quickly, particularly by launching the first successful human spaceflight. The Soviet Union secretly pursued the Vostok programme in competition with the United States' Project Mercury. Vostok launched several precursor uncrewed missions between May 1960 and March 1961, to test and develop the Vostok rocket family and space capsule. These missions had varied degrees of success, but the final two—Korabl-Sputnik 4 and Korabl-Sputnik 5—were complete successes, allowing the first crewed flight.
Pilot.
The Vostok 1 capsule was designed to carry a single cosmonaut. Yuri Gagarin was chosen as the prime pilot of Vostok 1, with Gherman Titov and Grigori Nelyubov as backups. These assignments were formally made on April 8, four days before the mission, but Gagarin had been a favourite among the cosmonaut candidates for at least several months.
The final decision of who would fly the mission relied heavily on the opinion of the head of cosmonaut training, Nikolai Kamanin. In an April 5 diary entry, Kamanin wrote that he was still undecided between Gagarin and Titov. "The only thing that keeps me from picking [Titov] is the need to have the stronger person for the one day flight." Kamanin was referring to the second mission, Vostok 2, compared to the relatively short single-orbit mission of Vostok 1. When Gagarin and Titov were informed of the decision during a meeting on April 9, Gagarin was very happy, and Titov was disappointed. On 10 April, this meeting was reenacted in front of television cameras, so there would be official footage of the event. This included an acceptance speech by Gagarin. As an indication of the level of secrecy involved, one of the other cosmonaut candidates, Alexei Leonov, later recalled that he did not know who was chosen for the mission until after the spaceflight had begun.
Preparations.
Unlike later Vostok missions, there were no dedicated tracking ships available to receive signals from the spacecraft. Instead they relied on the network of ground stations, also called Command Points, to communicate with the spacecraft; all of these Command Points were located within the Soviet Union.
Because of weight constraints, there was no backup retrorocket engine. The spacecraft carried 13 days of provisions to allow for survival and natural orbital decay in the event the retrorockets failed. The provisions included food for Gagarin. As focus was made on food that would not form crumbs, Gagarin was provided with liver meat puree and chocolate sauce, packed in metal toothpaste-style tubes.
The letters "СССР" were hand-painted onto Gagarin's helmet by engineer Gherman Lebedev during transfer to the launch site. As it had been less than a year since U-2 pilot Francis Gary Powers was shot down, Lebedev reasoned that without some country identification, there was a small chance the cosmonaut might be mistaken for a spy on landing.
Automatic control.
The entire mission would be controlled by either automatic systems or by ground control. This was because medical staff and spacecraft engineers were unsure how a human might react to weightlessness, and therefore it was decided to lock the pilot's manual controls. In an unusual move, a code to unlock the controls was placed in an onboard envelope, for Gagarin's use in case of emergency.278 Prior to the flight, Kamanin and others told Gagarin the code (1-2-5) anyway.
11 April 1961.
At Baikonur Cosmodrome on the morning of 11 April 1961, the Vostok-K rocket, together with the attached "Vostok 3KA" space capsule, were transported several kilometers to the launch pad, in a horizontal position. Once they arrived at the launch pad, a quick examination of the booster was conducted by technicians to make sure everything was in order. When no visible problems were found, the booster was erected on LC-1. At 10:00 (Moscow Time), Gagarin and Titov were given a final review of the flight plan. They were informed that launch was scheduled to occur the following day, at 09:07 Moscow Time. This time was chosen so that when the capsule started to fly over Africa, which was when the retrorockets would need to fire for reentry, the solar illumination would be ideal for the orientation system's sensors.273
At 18:00, once various physiological readings had been taken, the doctors instructed the cosmonauts not to discuss the upcoming missions. That evening Gagarin and Titov relaxed by listening to music, playing pool, and chatting about their childhoods. At 21:50, both men were offered sleeping pills, to ensure a good night's sleep, but they both declined. Physicians had attached sensors to the cosmonauts, to monitor their condition throughout the night, and they believed that both had slept well. Gagarin's biographers Doran and Bizony say that neither Gagarin nor Titov slept that night. Chief Designer Sergei Korolev did not sleep that night, due to anxiety caused by the imminent spaceflight.273
Gagarin statement before the mission.
Before the mission, Gagarin made a statement to the press, addressed to the Soviet Union and to the whole world:
 ;templatestyles src="Template:Blockquote/styles.css" / ;Dear friends, both known and unknown to me, fellow countrymen, men and women of all lands and continents! ;br ;In a few minutes a mighty spaceship will take me into the far-away expanses of the Universe. What can I say to you in these last minutes before the start? I see my whole past life as one wonderful moment. Everything I have experienced and done till now has been in preparation for this moment. You must realise that it is hard to express my feelings now that the test for which we have been training ardently and long is at hand. I don't have to tell you what I felt when it was suggested that I should make this flight, the first in history. Was it joy? No, it was something more than that. Pride? No, it was not just pride. I felt very happy - to be the first in space, to engage in an unprecedented duel with Nature - could one dream of anything greater than that? ;br ;But then I thought of the tremendous responsibility of being the first to accomplish what generations of people had dreamed of, the first to show man the way into space... Can you think of a task more difficult than the one assigned to me. It is not responsibility to a single person, or dozens of people, or even a collective. It is responsibility to all Soviet people, to all mankind, to its present and its future. And if I am nevertheless venturing on this flight, it is because I am a Communist, because I draw strength from unexampled exploits performed by my compatriots, Soviet men and women. I know that I shall muster all my will power the better to do the job. Realising its importance, I will do all I can to carry out the assignment of the Communist Party and the Soviet people. ;br ;Am I happy to be starting on a space flight? Of course I am. In all times and all eras man's greatest joy has been to take part in new discoveries. ;br ;I would like to dedicate this first space flight to the people of communism, a society which our Soviet people are already entering, and which, I am confident, all men on earth will enter. ;br ;It is a matter of minutes now before the start. I say to you good-bye, dear friends, just as people say to each other when setting out on a long journey. I would like very much to embrace you all - people known and unknown to me, close friends and strangers alike. ;br ;See you soon!
In his autobiography, Gagarin recalled that, looking at the spacecraft before start, he was "seized with an unprecedented rise of all mental strength ;... ; some extraordinary words were born that I had never used before in everyday speech." This was not true; according to historian Asif Siddiqi, Gagarin "was essentially forced to utter a stream of banalities prepared by anonymous speechwriters" taped much earlier in Moscow.274
Flight.
At 05:30 Moscow time, on the morning of 12 April 1961, both Gagarin and his backup Titov were woken. They were given breakfast, assisted into their spacesuits, and then were transported to the launch pad. Gagarin entered the "Vostok 1" spacecraft, and at 07:10 local time (04:10 UTC), the radio communication system was turned on. Once Gagarin was in the spacecraft, his picture appeared on television screens in the launch control room from an onboard camera. Launch would not occur for another two hours, and during the time Gagarin chatted with the mission's main CapCom, as well as Chief Designer Sergei Korolev, Nikolai Kamanin, and a few others,274 periodically joking and singing songs. Following a series of tests and checks, about forty minutes after Gagarin entered the spacecraft, its hatch was closed. Gagarin, however, reported that the hatch was not sealed properly, and technicians spent about 15 minutes removing all the screws and sealing the hatch again. According to a 2014 obituary, Vostok's chief designer, Oleg Ivanovsky, personally helped rebolt the hatch. There is some disagreement over whether the hatch was in fact not sealed correctly, as a more recent account stated the indication was false.
During this time Gagarin requested some music to be played over the radio. Korolev was reportedly suffering from chest pains and anxiety, as up to this point the Soviet space launch rate was 50% (12 out of 24 launches had failed). Two Vostoks had failed to reach orbit due to launch vehicle malfunctions and another two malfunctioned in orbit. Korolev was given a pill to calm him down. Gagarin, on the other hand, was described as calm; about half an hour before launch his pulse was recorded at 64 beats per minute.276
Time in orbit.
The automatic orientation system brought Vostok 1 into alignment for retrofire about 1 hour into the flight.
Reentry and landing.
At 07:25 UTC, the spacecraft's automatic systems brought it into the required attitude (orientation) for the retrorocket firing, and shortly afterwards, the liquid-fueled engine fired for about 42 seconds over the west coast of Africa, near Angola, about uprange of the landing point. The orbit's perigee and apogee had been selected to cause reentry due to orbital decay within 13 days (the limit of the life support system function) in the event of retrorocket malfunction. However, the actual orbit differed from the planned and would not have allowed descent until 20 days.
Ten seconds after retrofire, commands were sent to separate the Vostok service module from the reentry module (code name "little ball" ()), but the equipment module unexpectedly remained attached to the reentry module by a bundle of wires. At around 07:35 UTC, the two parts of the spacecraft began reentry and went through strong gyrations as Vostok 1 neared Egypt. At this point the wires broke, the two modules separated, and the descent module settled into the proper reentry attitude. Gagarin telegraphed "Everything is OK" despite continuing gyrations; he later reported that he did not want to "make noise" as he had (correctly) reasoned that the gyrations did not endanger the mission (and were apparently caused by the spherical shape of the reentry module). As Gagarin continued his descent, he remained conscious as he experienced about 8 g during reentry. (Gagarin's own report states "over 10 g".)
At 07:55 UTC, when Vostok 1 was still from the ground, the hatch of the spacecraft was released, and two seconds later Gagarin was ejected. At altitude, the main parachute was deployed from the Vostok spacecraft.
Gagarin's parachute opened almost immediately, and about ten minutes later, at 08:05 UTC, Gagarin