To celebrate the 48th anniversary of the Apollo 11 lunar landing, Sotheby’s New York held a special space exploration-themed auction on July 20th. One of the hot-ticket items, a zippered bag laced with moon dust, sold for $1.8 million, the Associated Press reports. The bag’s previous owner is likely thrilled, but NASA certainly isn’t celebrating. The agency recently fought, and lost, a bitter court battle to retrieve the artifact from a private collection.

The bag, which is stamped with the words “Lunar Sample Return,” was used by Neil Armstrong during the first manned mission to the moon in 1969. As Smithsonian.com’s Erin Blakemore wrote last August, the astronaut packed the bag with moon rocks so he could transport them back to Earth.

A $1.8 million selling price is certainly nothing to sneeze at, but the bag was actually a bit of a steal. Sotheby’s had estimated that it would be scooped up for between two and four million dollars. On the day of the auction, the bag didn’t come close to surpassing the price of Sotheby’s most expensive space artifact: the Soviet Vostok 3KA-2 capsule, which sold for $2.9 million in 2011.

While Armstrong’s lunar bag didn’t break any records, it has been the subject of frenzied discussion since NASA accidentally sold it to a private collector three years ago. As Blakemore explains, investigators found the bag while searching through the belongings of Max Ary, the former president of the Kansas Cosmosphere. In 2005, Ary was indicted of stealing and selling museum artifacts, including ones that had been loaned out by NASA.

“[D]ue to an error in NASA’s system, the bag was confused with another space bag from a later lunar landing, and was then accidentally sold to an Illinois woman for just $995 at auction,” Blakemore writes.

The buyer, one Nancy Carlson, knew that the bag had been used during a space flight, but she wasn’t sure which one. So she sent the bag of to NASA for testing. The agency, realizing its cosmic goof, refused to return the bag. The item “belongs to the American people,” NASA said in a statement at the time, according to the AP.

But U.S. District Judge J. Thomas Marten ruled in Carlson's favor. He said that while the bag should never have been put up for sale, he had no recourse to reverse the transaction. NASA was forced to return the artifact in February of 2017.

Carlson told CBS News that she decided to sell the bag because she was worried that it would not be safe in her home. But the pun-tastically named group For All Moonkind Inc., which advocates for the protection of Apollo Lunar Landing Sites, condemned her decision.

“The bag belongs in a museum, so the entire world can share in and celebrate the universal human achievement it represents,” Michelle Hanlon, the organization’s co-founder, said in a statement.

Sotheby’s has declined to release the name of the buyer. But there’s always the chance that he or she will decide to lend the precious artifact to a public institution, where it can be displayed for all to see.