Dinosaur skeleton and Martian meteorite to go under the hammer at Sotheby's 'Geek Week'

If you have a few million dollars to spare, you could soon be the owner of a juvenile ceratosaurus. The dinosaur skeleton is going under the hammer on Wednesday at Sotheby’s in New York, alongside a chunk of the planet Mars. They're part of the auction house's so-called 'Geek Week' natural science sale.

Found in Laramie, Wyoming in 1996, the young dinosaur’s 140 fossilized bones were carefully reassembled so it's ready to exhibit.

Cassandra Hatton is Vice Chairman, Science & Natural History at Sotheby’s: "This is one of only four ceratosaurus in the world. The three other examples are in museums. This is not only the only one that is available for purchase, but it's the only juvenile specimen."

The skeleton, which is more than 2 meters tall and nearly 3 meters long, is believed to be from the late Jurassic period, about 150 million years ago, Sotheby's says. It's auction estimate is 4 to 6 million dollars.

Ceratosaurus dinosaurs were bipeds with short arms that appear similar to the Tyrannosaurus rex, but smaller. Ceratosaurus dinosaurs could grow up to 7.6 meters long, while the Tyrannosaurs rex could be 12 meters long.

The skeleton was acquired last year by Fossilogic, a Utah-based fossil preparation and mounting company.

Martian meteorite

Also for sale, a 25 kilogram rock blown off the surface of Mars by a massive asteroid strike. It travelled more than 200 million kilometers before crashing into the Sahara Desert.

"This Martian meteorite is the largest piece of Mars we have ever found by a long shot," Hatton says. "So it's more than double the size of what we previously thought was the largest piece of Mars. And we've only taken a small piece of it to study, to confirm that it was Martian, but there's all sorts of interesting data that can be found inside of this rock.”

Found by a meteorite hunter in the Agadez Region of Niger in 2023, it’s a rare find. Of the 77,000 officially recognized meteorites found on Earth, Sotheby’s says only 400 are from Red Planet.

Hatton said a small piece of the red planet remnant was removed to study it and confirm it is Martian. The study found that it is an “olivine-microgabbroic shergottite,” formed from the slow cooling of Martian magma. It has a course-grained texture composed primarily of pyroxene, maskelynite, and olivine, Sotheby's says.

Roughly 38 by 30 by 15 centimeters, it also has a glassy surface, likely due to the high heat that burned it when it fell through Earth's atmosphere, Hatton said. “So that was their first clue that this wasn't just some big rock on the ground,” she said. It's not clear exactly when the meteoroid hit Earth, but testing shows it probably happened in recent years, Sotheby's said.