One space-geek collector could soon be over the moon.
A small white pouch marked “Lunar Sample Return,” which Nancy Lee Carlson bought two years ago for $995, is expected to fetch as much as $4 million at an upcoming Sotheby’s auction. That’s because it’s sprinkled with moon dust.
Astronaut Neil Armstrong filled the bag with rocks from the lunar Sea of Tranquility during his historic trip to the moon on the 1969 Apollo 11 mission. He turned the bag over to a Houston lab, which emptied it of the rocks and then lost track of it. It eventually turned up on a U.S. Marshals auction website.
Enter Carlson, a Chicago-area attorney. She bought the pouch — along with some other items, in a kind of space-memento grab bag — for $995 and sent it off to NASA for testing. NASA claimed the bag belonged to the agency, and wouldn’t return it until after a long court battle. You’d think Carlson was asking for the moon.
— Sotheby's (@Sothebys) May 21, 2017
Sotheby’s describes the pouch as “the most important space artifact to ever appear at auction.” It’s selling the item on July 20 — the 48th anniversary of humankind’s first moon landing.
However, NASA isn’t thrilled. Agency spokesman William Jeffs told The Wall Street Journal that the bag should be on public display and not hidden away in some private collection.
The bag “represents the culmination of a massive national effort involving a generation of Americans, including the astronauts who risked their lives in an effort to accomplish the most significant act humankind has ever achieved,” Jeffs said.
The bag is expected to go for such a sky-high price because NASA doesn’t allow anyone to own any bit of the moon — except for the bag.
Sotheby’s senior specialist Cassandra Hatton called the auction of the “modest bag” her “Mona Lisa moment.”
CORRECTION: A previous version of this story misstated the name of William Jeffs as Warren Jeffs.
This article originally appeared on HuffPost.