module for the International Space Station. After Zvezda, there was a hiatus in reusable projects until Buran. The Buran orbital vehicle program was developed in response to the U.S. Space Shuttle program, which raised considerable concerns among the Soviet military and especially Defense Minister Dmitry Ustinov. An authoritative chronicler of the Soviet and later Russian space programs, the academic Boris Chertok, recounts how the program came into being. According to Chertok, after the U.S. developed its Space Shuttle program, the Soviet military became suspicious that it could be used for military purposes, due to its enormous payload, several times that of previous U.S. launch vehicles. Officially, the Buran orbital vehicle was designed for the delivery to orbit and return to Earth of spacecraft, cosmonauts, and supplies. Both Chertok and Gleb Lozino-Lozinskiy (General Designer and General Director of NPO Molniya) suggest that from the beginning, the program was military in nature; however, the exact military capabilities, or intended capabilities, of the Buran program remain classified. Like its American counterpart, the Buran orbital vehicle, when in transit from its landing sites back to the launch complex, was transported on the back of a large jet aeroplane – the Antonov An-225 Mriya transport aircraft, which was designed in part for this task and was the largest aircraft in the world to fly multiple times. Before the Mriya was ready (after the Buran had flown), the Myasishchev VM-T Atlant, a variant on the Soviet Myasishchev M-4 Molot (Hammer) bomber (NATO code: Bison), fulfilled the same role. History of the Buran program Program development The development of the Buran began in the early 1970s as a response to the U.S. Space Shuttle program. Soviet officials were concerned about a perceived military threat posed by the U.S. Space Shuttle. In their opinion, the Shuttle's 30-ton payload-to-orbit capacity and, more significantly, its 15-ton payload return capacity, were a clear indication that one of its main objectives would be to place massive experimental laser weapons into orbit that could destroy enemy missiles from a distance of several thousands of kilometres. Their reasoning was that such weapons could only be effectively tested in actual space conditions and that to cut their development time and save costs it would be necessary to regularly bring them back to Earth for modifications and fine-tuning. Soviet officials were also concerned that the U.S. Space Shuttle could make a sudden dive into the atmosphere