Niger wants answers after largest piece of Mars sold at auction for more than $5 million

It's the largest piece of Mars ever found on Earth — a 54-pound meteorite that fetched more than $5 million at a New York auction last month, setting a world record.

But in the West African nation of Niger, where the rusty-red rock was unearthed in the Sahara Desert, officials have launched an investigation into what they call possible "illicit international trafficking," claiming it may have been smuggled out of the country. Sotheby's, the auction house, has disputed the claim.

The government of Niger says it has launched an official investigation "to identify the circumstances of its discovery and sale." While the country doesn't have specific legislation regarding meteorites, an international heritage law is being looked into. Here's what to know about the meteorite and the legal dispute:

How the meteorite was found

Sotheby's said the rock, named NWA 16788, was blown off the surface of Mars by a massive asteroid strike and traveled 140 million miles to Earth.

"The odds of this getting from there to here are astronomically small," Cassandra Hatton, Sotheby's vice chairman of science and natural history, said in an auction house video.

It was discovered in the Sahara in northwestern Niger by a meteorite hunter in November 2023, according to the auction house. His identity was not disclosed. Nor was the identity of the buyer last month.

(The largest ever Martian meteorite is on view for the first time at Sotheby's before an auction on July 8, 2025, in New York City.Selcuk Acar/Anadolu via Getty Images)

Meteorite hunting is growing in arid Saharan countries like Niger.

Though meteorites can fall anywhere on Earth, the Sahara has become a prime spot for their discovery in part due to the favorable climate for their preservation.

Hunters often search for space rocks that can be sold to collectors or scientists. The rarest and most precious are from Mars and the moon.

According to the Heritage academic journal, the rock was sold to an international dealer before it ended up in a private gallery in Italy. A team of scientists from the University of Florence examined the rock last year to learn more about its structure and where it came from before falling to Earth, the publication said.

The meteorite was also briefly on display in Rome before it was next seen in public in New York last month during the auction. It is the largest meteorite from Mars, but not the largest meteorite ever found. According to NASA, a meteorite originally weighing over 100 tons once fell in Namibia.