Answer
Yes, Mirosław Hermaszewski is the only Polish national to have been in space. He flew aboard the Soyuz 30 mission to the Salyut 6 space station in 1978, spending over 8 days in space. During the mission, he conducted various scientific experiments and observations related to Earth resources, astronomy, and materials science. Hermaszewski's spaceflight holds historical significance as a milestone achievement for Poland's space program.