Question: What was originally the primary focus of the sci-fi magazine Starlog, which included among its editors Robert Greenberg?

Context paragraphs:
Robert Greenberg (disambiguation): Robert Greenberg is a musician

Model Rocketry (magazine): Model Rocketry was an American hobbyist magazine published from October 1968 to February 1972.  The Editor and Publisher was George J. Flynn and the Managing Editor was Gordon K. Mandell.  Other members of the editorial and business staffs, some of whom held several positions at various times during the years the magazine was published, were Assistant Editors Robert B. Singer (November 1969 to November 1971) and Robert Parks (July 1970 to February 1972); Technical Editor Douglas J. Malewicki (November 1969 to February 1972); Business Managers George J. Caporaso (October 1968 to August 1969), Jerome Apt, III (Jay Apt) (September 1969 to December 1970), Thomas T. Milkie (January to November 1971), and Arthur H. (Trip) Barber (December 1971 to February 1972); Technical Correspondent George J. Caporaso (September 1969 to February 1972); Distribution Managers Thomas T. Milkie (October 1968 to October 1969), Kevin P. Brown (November 1969 to December 1970), and Steven Glines (January 1971 to February 1972); and Art Director Thomas T. Milkie (November and December 1969).  The magazine was published by Model Rocketry, Inc., a closely held corporation owned by founding staff members George J. Flynn, Gordon K. Mandell, George J. Caporaso, and Thomas T. Milkie and members of their families.  Its paid circulation reached 15,000 by 1970.

LA Gear: LA Gear (or L.A. Gear) is an American shoe company based in Los Angeles, California.  Founded by Robert Greenberg in 1979 and currently owned by ACI International.

Eegee's: Eegee's (stylized eegee's) is a chain of 26 restaurants in the greater areas of Tucson, Arizona and Phoenix, Arizona, as well as one in Casa Grande, Arizona.  It specializes in submarine sandwiches (subs) and salads, but it is most famous for its frozen fruit drinks, officially called "eegee's drinks" but colloquially known simply as an "eegee's."  It was founded in 1971 by Edmund Irving and Robert Greenberg, who combined their initials ("E" from Edmund and "G" from Greenberg) to create the name "eegee's."  The company has been highly noted for its social and environmental involvement, such as its tradition of donating time, food, and money to local charities; the collection of donations for local charitable organizations; instituting the community recycling program 'Recycle for People First!' ; and its program for training and employing the mentally disabled.  It is owned and operated by CEO Foods, Inc.

Rowena Green Matthews: Rowena Green Matthews is the G. Robert Greenberg Distinguished University "professor emeritus" at the University of Michigan, Ann Arbor.  Her research focuses on the role of organic cofactors as partners of enzymes catalyzing difficult biochemical reactions, especially folic acid and cobalamin (vitamin B12).  Among other honors, she was elected to the National Academy of Sciences in 2002 and the Institute of Medicine in 2004.

Geoff Nelder: Geoff Nelder is a British freelance editor and author.  He has written both fiction and non-fiction, and his research in the field of air pollution and climate won him a fellowship with the Royal Meteorological Society.  Nelder's fictional work falls in the genres of science fiction, fantasy and thrillers, and he is known for his sci-fi series "ARIA", which won him a "Preditors & Editors Award for best science fiction novel".  Nelder also published the sci-fi magazine "Escape Velocity", which launched in 2009.  Prior to moving to writing as his primary occupation, Nelder has worked as a teacher at Queens Park High School for 26 years.

Guru Dutt: Vasanth Kumar Shivashankar Padukone (9 July 1925 – 10 October 1964), better known as Guru Dutt, was an Indian film director, producer and actor.  He made 1950s and 1960s classics such as "Pyaasa", "Kaagaz Ke Phool", "Sahib Bibi Aur Ghulam" and "Chaudhvin Ka Chand".  In particular, "Pyaasa" and "Kaagaz Ke Phool" are now included among the greatest films of all time, both by Time magazine's "All-TIME" 100 best movies and by the "Sight & Sound" critics' and directors' poll, where Dutt himself is included among the greatest film directors of all time.

Robert Greenberger: Robert "Bob" Greenberger (born July 24, 1958) is an American who is known for his work as an editor for "Comics Scene", "Starlog", and "Weekly World News", as well as holding executive positions at both Marvel Comics and DC Comics.  He is also an elected office holder in his home of Fairfield, Connecticut.

Toni Jerrman: Toni Jerrman (born 1964) is critic and editor of the Finnish sci-fi magazine "Tähtivaeltaja".

Starlog: Starlog was a monthly science fiction magazine that was created in 1976 and focused primarily on Star Trek at its inception.  Kerry O’Quinn and Norman Jacobs were its creators and it was published by Starlog Group, Inc. in August 1976.  "Starlog" was one of the first publications to report on the development of the first "Star Wars" movie, and it followed the development of what was to eventually become "" (1979).

Supporting paragraphs: Robert Greenberger Starlog
Answer: Star Trek