The Story of... When collectors celebrate Moon anniversaries

Apollo 16, NASA's penultimate moon mission, was beset by difficulties. Following engine failure on the command module, the descent to the moon's surface was delayed over fears that it and the lunar module may not be able to reconnect.

After Thomas Mattingly successfully managed to refire the engine, John Young and Charles Duke touched down in the lunar highlands - the only mission to explore this area - and began 20 combined hours of exploration, bringing back 96kg of moon rock.

The two astronauts took two long lunar drives, heading into higher and more rugged terrain than previous missions. The two crafts successfully reconnected and splashed down in the Pacific Ocean on April 27.

The command module is now on display at the US Space & Rocket Center in Huntsville, Alabama.

Anniversaries of significance in the history of space exploration can often offer a boost in the collectibles market and provide investors with a good opportunity for making a profit.

Ham's space flown tag is coming to auction at Bonhams

Bonhams' 2009 and 2010 Space History auctions were timed to coincide with the anniversaries of the Apollo 11 moon landing and Apollo 13's splashdown following its abortive attempt to reach the moon.

This year's May 5 event in New York marks the 50^th anniversary of Alan Shepard's suborbital flight, becoming the first American in space, just weeks behind Yuri Gagarin's historic first orbital flight.

Items of note include Ham the space chimp's space flown neck tag from January 1961, worth an estimated $4,000, and a photograph of the original seven astronauts from the Mercury space programme, signed by Scott Carpenter, Wally Schirra and Gordon Cooper, which has an estimate of $1,500.