Tags: Astronaut.
Sergei Konstantinovich Krikalev (Russian: Серге́й Константинович Крикалёв also transliterated as Sergei Krikalyov; born August 27 1958) is a Russian cosmonaut and mechanical engineer. As a prominent rocket scientist he is a veteran of six space flights and has spent more time in space than any other human: a total of 803 days 9 hours and 39 minutes. He retired from spaceflight since 2007 and is currently working as vice president of Space Corporation Energia.
