In this historical photo from the U.S. space agency, the Johnson Space Center's 1984 "roof" concept for a space station.
The "roof" was covered with solar array cells, that were to generate about 120 kilowatts of electricity. Within the V-shaped beams there would be five modules for living, laboratory space, and external areas for instruments and other facilities.
[Far Out Space Station Concepts by NASA (Gallery )]
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