NASA Scientists 'Astonished' by Unusual Martian Spheres

NASA have scientists discovered an unusual rock formation on the surface of Mars which could provide some insights into the red planet's history.

The Perseverance Science Team, a group of scientists remotely exploring Mars since 2021, was astonished by the discovery of a rock covered in strange bubbles, which may have been formed in a way unique to any other deposit on the red planet.

Found in Broom Point, at the lower slopes of the Witch Hazel Hill area on the rim of the Jezero crater, the rock—which scientists have dubbed "St. Pauls Bay"—is made up of hundreds of millimeter-sized, dark gray spheres, each with a different shape.

"Some of these occurred as more elongate, elliptical shapes, while others possessed angular edges, perhaps representing broken spherule fragments. Some spheres even possessed tiny pinholes!" said geologist Alex Jones of Imperial College London in a statement.

"What quirk of geology could produce these strange shapes?" he mused.

St. Pauls Bay came to the scientists attention when the Perseverance rover was sent to investigate a series of light and dark layered rocks that had been spotted from orbit.

Studying these layers can give scientists insights into the environmental conditions during the rocks' formation, which can help reconstruct Mars' geological history.

It was while the rover was sampling these rocks that the one bearing the strange spheres was sighted.

While this isn't the first time "blueberries" have been spotted on Mars, their peculiar shape suggests that they might have formed through a different process to those previously observed.

In 2004, the Mars Exploration Rover Opportunity spotted Martian Blueberries at Meridiani Planum and, since then, the Curiosity rover observed spherules in the rocks of Yellowknife Bay at Gale crater.

Most recently, Perseverance itself also found popcorn-like textures in sedimentary rocks exposed in the Jezero crater inlet channel, Neretva Vallis.

"In each of these cases, the spherules were interpreted as concretions, features that formed by interaction with groundwater circulating through pore spaces in the rock. Not all spherules form this way, however," Jones said.

"[Similar spherules] also form on Earth by rapid cooling of molten rock droplets formed in a volcanic eruption, for instance, or by the condensation of rock vaporized by a meteorite impact," Jones continued.

"Each of these formation mechanisms would have vastly different implications for the evolution of these rocks, so the team is working hard to determine their context and origin."

St. Pauls Bay appears to be a "float rock"—a term used by geologists to describe a rock that is not found in its original location.

The Perseverance Team is now working to link the bubbled-covered rock to the stratigraphy layers at Witch Hazel Hill previously observed from orbit.

"Placing these features in geologic context will be critical for understanding their origin, and determining their significance for the geological history of the Jezero crater rim and beyond!" Jones added.

Do you have a tip on a science story that Newsweek should be covering? Do you have a question about Mars? Let us know via science@newsweek.com.