The pulp era
Astounding Stories began in January 1930. After several changes in name and format (Astounding Science Fiction, Analog Science Fact & Fiction, Analog) it is still published today (though it ceased to be pulp format in 1943). Its most important editor, John W. Campbell, Jr., is credited with turning science fiction away from adventure stories on alien planets and toward well-written, scientifically literate stories with better characterization than in previous pulp science fiction. Isaac Asimov's Foundation Trilogy and Robert A. Heinlein's Future History in the 1940s, Hal Clement's Mission of Gravity in the 1950s, and Frank Herbert's Dune in the 1960s, and many other science fiction classics all first appeared under Campbell's editorship.
By 1955, the pulp era was over, and some pulp magazines changed to digest size. Printed adventure stories with colorful heroes were relegated to the comic books. This same period saw the end of radio adventure drama (in the United States). Later attempts to revive both pulp fiction and radio adventure have met with very limited success, but both enjoy a nostalgic following who collect the old magazines and radio programs. Many characters, most notably The Shadow, were popular both in pulp magazines and on radio.
Most pulp science fiction consisted of adventure stories transplanted, without much thought, to alien planets. Pulp science fiction is known for clichés such as stereotypical female characters, unrealistic gadgetry, and fantastic monsters of various kinds. However, many classic stories were first published in pulp magazines. For example, in the year 1939, all of the following renowned authors sold their first professional science fiction story to magazines specializing in pulp science fiction: Isaac Asimov, Robert A. Heinlein, Arthur C. Clarke, Alfred Bester, Fritz Leiber, A. E. van Vogt and Theodore Sturgeon. These were among the most important science fiction writers of the pulp era, and all are still read today.