This week marks the 50th anniversary of the Apollo 11 moon landing, and for space fans with deep pockets, it’s possible to own a piece of the historic mission.

Two prominent auction houses, Christie’s in New York City and Heritage Auctions in Dallas, are selling unique pieces of memorabilia from the flight that took astronauts Neil Armstrong, Buzz Aldrin and Michael Collins to the moon in 1969.

The Christie’s auction, set to take place Thursday, features a flight manual that sat between Armstrong and Aldrin in the lunar module that took them down to the moon’s surface. The manual, held together by three metal rings, contains flight plans, detailed procedures for the moon landing and handwritten annotations from the astronauts.

Christie’s estimates the flight manual could fetch up to $9 million.

The manual is one of several items that will be auctioned off to celebrate the 50th anniversary of Apollo 11. An autographed photo of Aldrin standing on the pockmarked surface of the moon already sold for $32,500 Thursday morning. The photo is inscribed with the words “Tranquility Base, July 20, 1969,” with Aldrin’s signature below.

The Armstrong family has partnered directly with Heritage Auctions to sell items from the Apollo 11 mission and Armstrong’s life before NASA. The sale began Tuesday and continues through Thursday.

Among the items already sold are a gold medal that flew with Armstrong to the moon that nabbed more than $2 million, a piece of cloth from the Wright Brothers’ 1903 Flyer that Armstrong brought on the Apollo 11 flight that sold for $143,750, and the moonwalker’s childhood teddy bear that sold for $3,500.

Neil Armstrong's childhood teddy bear. Heritage Auctions / HA.com

Heritage Auction’s Thursday sale includes two of Armstrong’s medals and original photos and magazines from the family’s personal collection.

Armstrong’s son, Mark Armstrong, said part of the proceeds from the auction will be used to support museums around the world that emphasize science, technology, engineering, math and the arts — including the Armstrong Air & Space Museum in Wapakoneta, Ohio, that was named for his famous father.

“I think the 50th anniversary is an opportunity for us to not only remember where we’ve been, but to inspire the next generation of young people,” Mark Armstrong told NBC News MACH.

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