Of all the different areas of collectibles, space memorabilia arguably offers the highest number of 'untapped' opportunities. This is because it remains so underappreciated for the rewards it can bring both as a passion and an investment.
In terms of legacy and provenance, the space suits, technologies and mission patches are among the greatest tributes to mankind's courage outside of war memorabilia.
And it was on this day, 41 years ago, that the "big daddy" of space missions took place: Apollo 11's Neil Armstrong and Buzz Aldrin took their first steps on the Moon.
Unsurprisingly, the most valuable piece of space memorabilia ever sold at auction is from the Apollo 11 mission - and was described by Buzz Aldrin as "the single most critical navigational device we used while on the Moon."
The piece in question was the chart used by Apollo 11 astronauts Neil Armstrong and Buzz Aldrin to determine their exact position on the lunar surface, immediately after their historic lunar landing in the Moon's Sea of Tranquility.
The star of Bonhams' blockbuster New York Space Sale in July 2009 - timed to coincide with Apollo 11's 40th anniversary - the chart sold for an incredible $218,000, including buyer's premium.
So successful was Bonhams' Space Sale that a sequel was held earlier this year on the 40th anniversary of Apollo 13, at which another iconic piece of Apollo 11 memorabilia was the star lot.
Bearing arguably the most memorable words of the 20th century, a flight plan for Armstrong, Aldrin and Michael Collins' mission inscribed with the words "One small step for a man—one giant leap for mankind" by Armstrong himself appeared for sale.
Aside from Armstrong's landmark words - up there with Martin Luther King's I Have a Dream and Winston Churchill's "We shall fight on the beaches..." speeches - the document also included detailed preparation notes for Man's first step on the Moon.
A truly one-of-a-kind piece of historic memorabilia from mankind's greatest 20th century achievement, the inscribed flight plan was bought by a lucky collector for $152,000.
Often as fascinating and as valuable as the memorabilia used during the Moon missions themselves are the artefacts which reveal the stories behind the astronaut's brave feats.
For instance, people often forget that these astronaut's put their lives on the line in the name of exploration, endeavour and progress...
Apollo 11 was the first flight in which insurance covers were used. They were produced for the crew to sign together in pre-flight quarantine, shortly before their launch to the Moon.
The covers were then left with the astronauts' families as a form of insurance, in the event that the intrepid crew should fail to return from their perilous mission.
Some of the covers were postmarked July 16, 1969, the day of launch, with the remainder postmarked in Houston on July 20, 1969, the day of the landing. Each bore the blue felt-tipped signatures of "Neil Armstrong," "Michael Collins" and "Buzz Aldrin".
Estimated at $6,000-8,000, the insurance covers doubled their lower estimate to sell for $10,258. Elsewhere on the market, a set of 'insurance' envelopes signed by Buzz Aldrin sold for $15,860.
In a similar vein, a personal cheque signed by Neil Armstrong on the day of his lunar mission sold for a record $27,350.
Astonishingly, its minimum bid price was only $500 - the cheque brought 54 times the price, which shows how much people underestimate the value of space memorabilia (especially considering that Neil Armstrong lives the life of a virtual recluse and is the world's rarest living signature).
And did you know that, as well as being a nifty Lunar Command Module pilot, Michael Collins also had a talent for design?
Indeed, it was Collins who drafted the original design for Apollo 11's insignia of an eagle landing on the Moon with an olive branch in its beak (pictured below).
Flown to the Moon and consigned from the collection of Ron Evans, who worked at mission control during the Apollo 11 mission and later piloted Apollo 17, a medallion bearing Collins' original design sold for $20,315 earlier this year.
Finally, and although it has yet to be made available on the private market, there is another piece of memorabilia that is perhaps the ultimate testament to the Bravery of the Apollo 11 crew: the speech that US President Nixon would have read out if they hadn't survived.
Written by the late William Safire, presidential speechwriter, author and journalist, the unused speech reads: "Fate has ordered that the men who went to the moon to explore in peace will stay on the moon to rest in peace."
"These brave men, Neil Armstrong and Edwin Aldrin, know that there is no hope for their recovery. But they also know that there is hope for mankind in their sacrifice."
Exactly 41 years after mankind set foot on the Moon, the legacy of their brave feat remains one of Mankind's ultimate 20th century achievements.
If you missed out of the above sales, but are interested in getting involved in this highly investible area of collecting, Paul Fraser Collectibles has one of the world's largest inventories of NASA memorabilia which you can see here.
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