Justina Marsh and Peter Marsh - Zecharia Sitchin (Russian: Заха́рия Си́тчин; July 11, 1920 – October 9, 2010) was an Azerbaijani-born Russian-American author of books proposing an explanation for human origins involving ancient astronauts. Sitchin attributed the creation of the ancient Sumerian culture to the Anunnaki, which he stated was a race of extraterrestrials from a planet beyond Neptune called Nibiru. He asserted that Sumerian mythology suggests that this hypothetical planet of Nibiru is in an elongated, 3,600-year-long elliptical orbit around the sun. Sitchin's books have sold millions of copies worldwide and have been translated into more than 25 languages.

Sitchin's ideas have been rejected by scientists and academics, who dismiss his work as pseudoscience and pseudohistory. His work has been criticized for flawed methodology and mistranslations of ancient texts as well as for incorrect astronomical and scientific claims.