The first manned space flight of a US astronaut (John Glenn) took place on February 20, 1962, under the name “Project Mercury”. Glenn circled the Earth 3 times in an orbit before he returned after 4 hours and 55 minutes flight time. The US Post had a stamp prepared in secrecy for the event. While Glenn was still in space, the stamp commenced to be sold in larger postal offices.

Before Glenn was back to Earth all 120 million copies of the stamp were sold. The speed of the sale was also attributable to the fact that rumors had spread relating to the usual inscription “U.S. Postage” missing on the stamp. Therefore it was assumed the stamp was a misprint and would be withdrawn.

The US Post however commented that the inscription was not mandatory on US stamps and there was nothing out of the ordinary. Additional editions of the stamp resulted in a total of 289.240.000 stamps sold.