This time we should engage with the various critical texts, so just a little bit of information about their authors:
Stefan Kisielewski (1911-1991) was an important Polish writer and thinker who began his adult life as a musician. He was active in Catholic groups, and the article is from a book of articles (published in the Cold War era, as you can sort of tell from the brief bio that begins his piece) intended to give Western readers more information about Polish culture.
Stefan Źółkiewski (1911-1991) was a founder of the Polish Workers' Party, editor for years of one of the Party newspapers, and less present than Kisielewski in the sources I checked to find this information for you.
Mary Roach is an author (of Packing for Mars: The Curious Science of Life in the Void, among other things); this brief and enjoyable piece is meant to give you an idea of the cult of cosmonauts in the Soviet period, which continued to be important even after 1991. (In today's slang riot police are sometimes called "cosmaunauts" (космонавты) because of their big helmets and other protective gear.)
Stanisław Lem you already know; here he is in his critical incarnation.
Fredric Jameson (born 1934) is a hotshot literary critic and theorist who often applies Marxist criticism. This chapter is taken from Archaeologies of the Future: The Desire Called Utopia and Other Science Fictions (2005), a book dedicated to Darko (Suvin), among others.
Carl Freedman is the author of Critical Theory and Science Fiction (2000); this article is an earlier part of that project.