The longest manned spaceflight was made by Valeri Vladimirovich Polyakov. He spent a total of 437 consecutive days in space from August 29, 1988, to April 29, 1989.
Valeri Vladimirovich Polyakov, a cosmonaut, was born on April 27, 1942, Tula City, USSR. Prior to being adopted in 1957, he first used the name Valeri Ivanovich Korshunov.
In 1959, he attended Tula Secondary School and then went to First Moscow State Medical University. Polyakov earned his doctorate in the said institution and then specialized in Astronautics Medicine in Moscow at the Institute of Medical and Biological Problems under the Ministry of Public Health. On October 12, 1964, Dr. Boris B. Yegorov, the first physician to fly to space, flew to space, boarded the Voshkod (Sunrise) 1 from Baikonur Space Center situated in Kazakhstan. The event resulted in Polyakov’s decision to specialize in Space Medicine.
On March 22, 1972, Polyakov was selected to be a cosmonaut in Medical Group 3 that would join the Russian team. It was referred to be his training as a physician that could provide medical and surgical assistance while in orbit. Before flying to space, he provided medical support work for the Soyuz spacecraft crew and attended spaceflight training at the Salyut space station.
His first spaceflight happened on August 29, 1988, onboarding the Soyuz TM-6. The Soyuz then connected to the Mir space station. Here Polyakov acted as a research-cosmonaut and studied the impacts of microgravity on humans. He returned to Earth on April 29, 1989, 240 days later aboard the TM-7. In the latter part of the year, he was appointed to be the head of the Institute of Medical and Biological Problems and was tasked to improve the strategies on the executive medical support provided to the Mir space station missions.
It was in Polyakov’s second spaceflight, where he began to shatter records and make a legacy of his own. On January 8, 1994, Polyakov returned to space, spending a total of 437 days, the longest human spaceflight in history in terms of consecutive days, aboard the Mir space station. During his stay, he performed scientific research, conducted experiments, traveled 186,887,000 miles, and completed more than 7,000 orbits around Earth.
On January 9, 1995, on his 366th day in space, Polyakov officially shattered the record for the longest spaceflight duration, previously held by Musa Manarov and Vladimir Titoy six years earlier.
Polyakov returned to Earth on March 22, 1995, aboard the Soyuz TM-20. He opted not to be carried between the capsule and the lawn chair and insisted on walking the short distance upon landing. Polyakov wanted to prove that it can be possible for humans to work on Mars’ surface even after a long transit duration.
After all, he submitted himself for this 437-day flight to know more about the human body’s response when exposed to microgravity environments. The information would be valuable for long missions and expeditions to Mars.
Upon arriving from his second flight outside the Earth, Polyakov also held the record for most cumulative time in space. It was soon shattered by Sergei Avdeyev with 747 cumulative days in space. Gennady Padalka now holds the record with a total of 879 days in space.
All data gathered from Polyakov’s missions were used by scientists and researchers to determine that humans can keep a sound mental state even on long missions just as how a typical human would do on Earth.
Polyakov has earned several awards and academic achievements for his spaceflight, including Hero of the Russian Federation, Hero of the Soviet Union, Order of the Legion of Honor, Order of Parasat, and the Order of Lenin. He was also able to publish various works regarding life sciences, medical intricacies of space missions, and the research he conducted during his long-duration spaceflights.
But, how long can astronauts really stay in weightlessness? First, we know that staying in the space environment for an extended period has negative impacts on the body. Some of the effects of long-term weightlessness may include deterioration of the skeleton, muscle atrophy, decreased production of red blood cells, slowing of cardiovascular functions, eyesight and balance disorders, and alterations in the immune system. But, when it comes to exact duration how long a human can stay in a spaceflight, no one could ever tell. Every new mission provides scientists and researchers new information that allow us to adjust our space protocols and lengthen the period each other time we send people to space.