The Omega Speedmaster Professional reference 3578.51, released in 2003, is the first “Snoopy” Speedmaster. It is a 42 mm stainless steel manual-wind chronograph using calibre 1861, with a sapphire crystal and a solid caseback engraved with the silver Snoopy design and a message from the Apollo 13 story. I could not confirm every detail of the caseback text from a single source.

It commemorates the Silver Snoopy Award that NASA gave Omega after the Apollo 13 mission in 1970 and was the first Speedmaster to carry the Snoopy design. The Snoopy name now covers several later models, including the 2015 and 2020 versions with the cartoon on the dial.

Collectors regard the 3578.51 as the original Snoopy and prices have risen strongly. It is no longer produced, although Omega’s Snoopy line continues with modern references.