How many letters does the top answer for “wrote the space merchants” have?

The most common answer is kornbluth (9 letters).

Crossword clue: wrote the space merchants

2 answers found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

kornbluth 9 letters wd-fact-v3

pohl 4 letters wd-fact-v3

author of the space merchants 50% similar → kornbluth, pohl

wrote 2001: a space odyssey 50% similar → clarke, kubrick

wrote the space trilogy 50% similar → lewis