In 1947, an amateur pilot named Kenneth Arnold claimed he saw nine crescent-shaped objects in the sky flying near Mount Rainier in Washington. He told a newspaper that he saw "saucers skipping on water," but the paper misquoted him, and the term "flying saucer" was born. The following year, the United States Air Force created the designation "Unidentified Flying Object" (UFO), and the rest is spaceship history.

Soon thereafter flying saucers, and their inhabitants, invaded the public’s imagination, as well as that of movie producers and science fiction authors — not to mention a few architects. Flying saucer-inspired buildings afforded reference to popular culture while simultaneously allowing for some great mid-century design elements. And it didn’t stop there; with all things mid-century in vogue again, a new crop of UFO buildings has risen. So in celebration of World UFO Day (yes, there is such a thing) on July 2, here are some stellar examples of spaceship buildings, from mid-century retro to slick and modern.

1. Chemosphere, Los Angeles, 1960

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Photo: Nick Neyland/flickr

Designed by influential American architect John Lautner, the mod octagon house was one declared, "the most modern home built in the world," by Encyclopedia Britannica. Since 2000, the restored Chemosphere has been the L.A. home of Benedikt Taschen of the German publishing house Taschen. 

2. Futuro House, 1960s

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Photo: Jeremy Sternberg/flickr

Designed by Finnish architect Matti Suuronen as a semi-portable ski lodge, fewer than 100 Futuro Houses were built before production was stopped. Public reaction was mixed, and since they were made of primarily reinforced plastic, the 1973 oil crisis made them prohibitively expensive to manufacture. 

3. Toronto City Hall, Toronto, 1965

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Photo: timtom.ch/flickr

Designed by Finnish architect Viljo Revell after winning a design competition with entries from 42 countries, the saucer-like structure in the middle houses the council chamber.

4. Sanzhi Pod City, New Taipei City, Taiwan, 1978

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Photo: vicjuan/flickr

The complex of colorful UFO-shaped houses was planned as a seaside destination for vacationing American military staff posted in Asia, but it was never finished and the project went bankrupt. Despite a petition to save them, they were demolished several years ago to make room for a modern resort.

5. Buzludzha Monument, Central Stara Planina, Bulgaria, 1981

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Photo: KamrenB Photography/flickr

Built by the Bulgarian communist regime to commemorate the socialists secret assembly to form an organized socialist movement in 1891 (because nothing says "go socialism!" like a flying saucer made of concrete). The monument is now abandoned and falling into disrepair.

6. Circus building, Astana, Kazakhstan, 2005

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Photo: unci_narynin/flickr

Home of Astana’s Metropolitan Circus, the whimsical arena is par for the course for the eccentric capital of Kazakhstan; among the other strangely futuristic structures is the Norman Foster-designed Khan Shatyr, a mall that doubles as the world's largest tent.

7. Shanghai Arena, Shanghai, China, 2007

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Photo: stefano meneghetti/flickr

Formerly the Shanghai World Expo Cultural Center designed by architecture firm, ECADI, for the 2010 World Expo, the super-sleek spacecraft-styled building was renamed the Mercedes-Benz Arena following agreement for a 10-year sponsorship by the motor company.

8. Emergencies Control Center, Tbilisi, Georgia, 2012

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Photo: Georgiabout.com

The mod spacecraft serves as the emergency control center to unify fire, rescue, medical emergency and patrolling services. And perhaps emergencies like UFO sightings? Tbilisi is home to a famous one.

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