NEW YORK — For sale: a 54-pound rock. Estimated auction price: $2 million to $4 million. Why so expensive? It’s the largest piece of Mars ever found on Earth.

Sotheby’s in New York will be auctioning what’s known as NWA 16788 on Wednesday as part of a natural history-themed sale that also includes a juvenile Ceratosaurus dinosaur skeleton that’s more than 6 feet tall and nearly 11 feet long.

According to the auction house, the meteorite is believed to have been blown off the surface of Mars by a massive asteroid strike before traveling 140 million miles to Earth, where it crashed into the Sahara. A meteorite hunter found it in Niger in November 2023, Sotheby’s said.

The red, brown and gray chunk is about 70% larger than the next largest piece of Mars found on Earth and represents nearly 7% of all the Martian material currently on this planet, Sotheby’s said. It measures nearly 15 inches by 11 inches by 6 inches.

It’s not clear exactly when the meteorite hit Earth, but testing shows it probably happened in recent years, Sotheby’s said.

— The Associated Press