The R/V Akademik Mstislav Keldysh (Russian: Академик Мстислав Келдыш) is a 6,240 ton Russian scientific research vessel. It has made over 50 voyages, and is best known as the support vessel of the Mir submersibles. The vessel is owned by the Shirshov Institute of Oceanology of the Russian Academy of Sciences in Moscow, and is homeported in Kaliningrad on the Baltic Sea. Named after the Soviet mathematician Mstislav Keldysh, it usually has 90 people on board (45 crew members, 20 or more pilots, engineers and technicians, 10 to 12 scientists and about 12 passengers). Among its facilities are 17 laboratories and a library.