The three previous auctions have raised a total of about $12 million, according to the Cincinnati Enquirer.
Armstrong, who died in 2012 at age 82, was a native of the Cincinnati area, having been born in Wapakoneta, about 112 miles north of the city.
Rick and Mark Armstrong, sons of the first man to step foot on the lunar surface, on July 20, 1969, told the newspaper they’ve made numerous charitable donations of memorabilia since the death of their father, who reportedly refused to commercialize his place in history.
“Contrary to what you may have heard from others, my brother and I have been very sensitive to this issue since my father’s passing,” Mark Armstrong wrote in an email, according to the Enquirer.
Items to be up for bid Friday at a Heritage Auctions in Dallas include commemorative medals, small state flags that traveled aboard Apollo 11, and a flight path to the moon that was drawn and signed by Armstrong, the newspaper reported.
The auction will also include items signed by Buzz Aldrin and Michael Collins, the two other members of the Apollo 11 crew.