1986 - Halley's Comet Photograph

This is an 8 X 10 photograph issued in 1986 which is actually a copy of a 1910 photograph taken of Halley's Comet as seen on May 25, 1910 in Helwan, Egypt. - The photograph was issued along with a commemorative silver coin when the comet returned in March of 1986. -- Halley's Comet or Comet Halley, is the best-known of the short-period comets and is visible from Earth every 75–76 years. Halley is the only short-period comet that is clearly visible to the naked eye from Earth, and the only naked-eye comet that might appear twice in a human lifetime. Other naked-eye comets may be brighter and more spectacular, but will appear only once in thousands of years. Halley last appeared in the inner Solar System in 1986 and will next appear in mid-2061. -- The original photograph is from the original plate taken by Harold Knox-Shaw (1885-1970), who worked at the Helwan Observatory in Egypt from 1907 to 1924. The Observatory was equipped with a 30-inch (76 cm) reflector which had a 4" (10cm) Cooke photographic lens mounted for wide-angle shots.