Astron (wristwatch)

Seiko Quartz-Astron 35SQ

Type	Quartz
Display	Analogue
Introduced	1969

The Astron wristwatch, formally known as the Seiko Quartz-Astron 35SQ, was the world's first "quartz clock" wristwatch, i.e., one based on a quartz crystal oscillator. It is now registered on the List of IEEE Milestones as a key advance in electrical engineering.

The Astron was unveiled in Tokyo on December 25, 1969, after ten years of research and development at Suwa Seikosha (currently named Seiko Epson), a manufacturing company of Seiko Group. Within one week 100 gold watches had been sold, at a retail price of 450,000 yen (US$1,250) each (at the time, equivalent to the price of a medium-sized car). Essential elements included a quartz crystal oscillator (8,192 cyles/second), a hybrid integrated circuit, and a miniature stepping motor to turn its hands. The Astron was accurate to ±5 seconds per month, or one minute per year.

References and footnotes

• "IEEE History Center: Electronic Quartz Wristwatch, 1969". IEEE. http://www.ieeeghn.org/wiki/index.php/Milestones:Electronic_Quartz_Wristwatch%2C_1969. 
• "Seiko Quartz Astron 35SQ". Seiko Epson. http://global.epson.com/company/milestone_products/05_35sq.html. 
• "The Watch That Changed Horological History". Seiko Epson. http://global.epson.com/newsroom/epson_story/pdf/EpsonStory02E.pdf.