Bulgarian astronaut program
After discussions in 1964, the Bulgarian cosmonaut program began in 1977 when members of the Bulgarian People's Air Force were trained for space tasks. Georgi Ivanov flew in 1979 on Soyuz 33, which suffered engine failure in orbit. This resulted in a cancellation of the planned docking with Salyut 6 and a high-G re-entry after a little more than one day in space. In 1988 Aleksandr Aleksandrov flew on Soyuz TM-5 to the Mir Space Station, spending ten days in space.
- "Bulgaria in space". Sofia Globe. Retrieved 12 December 2017.
- "Bulgaria First Cosmonaut and Near Disaster of Soyuz 33". Blazing Bulgaria. Retrieved 12 December 2017.