HOUSTON, July 21 (Xinhua) -- The personal collection of Neil Armstrong, the first man to have set foot on the moon, is to be sold in a series of auctions later this year and in 2019.

The artifacts on offer range from those associated with Armstrong's historic 1969 lunar landing to his private mementos. They include pieces of a wing and propeller from the 1903 Wright Brothers' Flyer, a heavier than air aircraft, that the spaceman took with him to the moon; Apollo 11 Robbins medallions, silver medallions commemorating the launch, landing and return of the mission; a gold pin flown on Gemini VIII, the sixth earth-orbiting spacecraft in NASA's Gemini program; and important correspondence, according to Texas-based auction company Heritage Auctions that will be handling the auction.

Armstrong was one of the three astronauts on the Apollo 11 mission and one of the two who landed on the moon on July 20, 1969. The quote he made on landing on the moon -- "That's one small step for [a] man, one giant leap for mankind" -- has become a legend.

Armstrong died in 2012 and his two sons, left with a large collection of mementos after his death, felt the need to conserve, restore, and research them. The idea of auctioning thus came into their mind.

"I think he would be pleased to be remembered as being part of a program that demonstrated amazing things can be achieved when people come together to dedicate themselves towards a common goal," his son Rick Armstrong said.

The two have collaborated with a firm to document the artifacts' authenticity and provenance.

The auctions will be held on Nov. 1-2 this year, as well as in May and November of 2019, which marks the 50th anniversary of the Apollo 11 mission.