Russian cosmonaut Sergei Krikalev spent in orbit for a total of 803 days, which is a world record. At the same time it can be considered the owner of another record - the longest travel time among the inhabitants of our planet. According to the theory of relativity, the greater the speed at which the object moves, the more time for it slows down. Calculated that because of space flight, Krikalev at 1/48 of a second younger than if he had remained all the time in the world. In other words, the astronaut returned from orbit at a time point at 1/48 of a second later, the expected values under normal conditions.