The largest Martian meteorite sold for $5.3 million

A fragment of Mars of exceptional scientific and symbolic value has conquered the international art and science market: NWA 16788, the largest Martian meteorite ever found on Earth, sold at auction by Sotheby's in New York for the record sum of 5.3 million dollars (approximately 4.9 million euros), more than double the minimum estimate set at the start (between 2 and 4 million).

The scientific value

The meteorite, weighing 24.67 kg , was discovered in July 2023 in the Sahara desert of Niger, in the Agadez region, by a meteorite hunter. It is a fragment ejected from Mars millions of years ago following an asteroid impact, which traveled approximately 140 million kilometers through space before crashing into the African desert. According to experts, it alone represents approximately 6.5% of the Martian material known to Earth , a figure that attests to its extreme rarity.

The rock, with its distinctive reddish-brown color, is classified as a shergottite, a type of Martian volcanic meteorite. Mineralogical analysis revealed a coarse-grained composition dominated by pyroxene, olivine, and maskelynite, a glass formed by the enormous pressure of the impact that ejected it from Mars.

Italy's role in the discovery

But Italy plays a key role in this extraordinary discovery. Before the auction, the meteorite was entrusted to a research team from the University of Florence, led by Giovanni Pratesi, professor of mineralogy, who studied its composition and origin in detail. The research was conducted together with Annarita Franza and Xhonatan Shehaj, as part of the Space It Up project, funded by the Italian Space Agency and the Ministry of University and Research.

The Florentine team's studies, published in scientific journals such as Heritage and presented at the Lunar and Planetary Science Conference, suggest that NWA 16788 could contribute to a revision of the classification system for Martian meteorites, so unique is its size, composition, and state of preservation. "This is a discovery of extraordinary importance," said Cassandra Hatton, Vice President of Science and Natural History at Sotheby's. "This meteorite offers a tangible connection to Mars, a planet that has fascinated humanity for centuries."

Despite the purchase by a private collector— rumored to be a well-known Italian gallery owner —two slices of the meteorite will remain in Italy, held at the University of Florence as standard specimens available to the international scientific community.

The debate

Only about 400 Martian meteorites have been identified on Earth out of a total of nearly 80,000 extraterrestrial fragments. In 2021, a Martian fragment weighing just 1.4 grams was sold at Christie's for $13,750. NWA 16788 was officially recognized in the Meteoritical Bulletin in June 2024.

The record sale has reignited the debate among scientists about the appropriateness of allowing such highly valuable samples to end up in private hands. "Meteorites are cosmic archives," explained Paul Asimow, a geologist at Caltech, "and while it's possible to study small portions of them, it would be desirable for collectors to donate some to research." In the case of NWA 16788, Italy has already done its part. (by Paolo Martini )