11 October 2005: Russian Cosmonaut Krikalev becomes the Absolute Record Holder in Accumulated Space Flight Time

Ten years ago, on October 11th 2005 at 01:10:00 (UTC), the manned transport space vehicle “Soyuz TM - 6” landed in the north of Kazakhstan. Hours before, the eleventh expedition to the International Space Station (ISS) undocked and returned to Earth with the three crew members on board. Amongst them was the Russian pilot-cosmonaut Sergei K. Krikalev (Сергей Константинович Крикалёв), who completed his sixth orbital space flight mission over the period from 1988 to 2005. By ending this journey, the total cumulative time he spent in space summed up to 803 days, 9 hours, 39 minutes and 9 seconds and set the Absolute World Record in the category “Accumulated Space Flight Time”. In other words and to give a better idea of the dimension of this truly exceptional achievement: Krikalev spent 2 years, 10 weeks, 2 days, 22 hours, 1 minute and 9 seconds in space, including eight Extravehicular Activities (EVAs or space walks).

From Engineering and Aerobatics to Cosmonautics

Since he was a little boy, the Russian showed interest in air sports. After he graduated from secondary school, his choice was either to become a military pilot and study engineering on the side or to study engineering and learn all he could about flying. Young Krikalev chose the second option, to study engineering and to join an Aero Club. He competed in aerobatic competitions, winning a national championship and a place on the Soviet national team. Already after four years of testing spaceflight equipment, developing spaceflight procedures and working in-flight control positions, in 1985 he was selected as a cosmonaut.

Over the timeframe of 17 years, the Russian went on six different missions. With the last one he exceeded the record of 748 days held of Sergei Avdeyev by 7.5%. ICARE President Anu Ojha OBE stated: “On April 12th 1961, Yuri Gagarin became the first human to orbit the Earth – and since then less than 560 other people have (to date) qualified as astronauts or cosmonauts by flying above the 100km “Karman Line” altitude used by FAI to signify the boundary between aeronautical and astronautical achievements.” According to Mr. Nicolas Bérend from the French Aerospace Lab ONERA, who functioned as ICARE Technical Expert to review the record claim, this number of space flights was reached by only seven other spacemen, including also one of the five longest spaceflights in history with his second mission aboard the Orbital Station MIR (microgravity research laboratory from 1986 – 2001).

“It is a beyond impressive spaceflight record, Mr. Krikalev has had the privilege of contributing to key events in the history of astronautics”,Mr. Bérend added, “he lead a new era of international cooperation in space at the same time as ISS itself.” In fact, Krikalev was inducted into the International Space Hall of Fame at the New Mexico Museum of Space History in 1993 and was quoted with: “The further you travel, the more you feel part of a big group of people. Traveling outside of Earth, I get this feeling of being part of mankind; it is an international adventure.” He retired from spaceflight in 2007 and today the 57-year old is a prominent rocket scientist and vice president of Rocket and Space Corporation Energia, a Russian manufacturer of spacecraft and space station components.

Time traveler by 0.02 seconds

A captivating detail about this record is the effect of time dilation during his flights. He has actually lived for 0.02 seconds less than everyone else on Earth, this means, he has travelled 0.02 seconds into his own future! The calculation relies on Albert Einstein's theories of relativity, which state that the passage of time is relative and diverse for two objects moving at different speeds (special relativity) or experiencing different levels of gravity as they are slightly further away from the center of the planet (general relativity). The effect of their speed relative to the Earth – special relativity - will be to “slow down” an astronaut’s clock relative to a clock on Earth, whilst the effect of their increased gravitational distance from Earth – general relativity - would be to “speed up” their clock relative to a clock on Earth. Both of these competing effects must be measured and combined to give the overall effect for any spacecraft – and for an astronaut aboard the ISS at an altitude of 400km, it’s the special relativity effect that dominates, slowing down their internal clocks compared to clocks on Earth. Over the 803 days of his missions, the cumulative time difference between Krikalev’s internal space clock and a clock on Earth totals around 0.02 seconds. He is a genuine time-traveller!