MADRID, 14 (EUROPA PRESS)
NASA's Perseverance rover has discovered a curious volcano-shaped rock on the surface of Mars that resembles a worn battle helmet.
Captured by the rover's Mastcam-Z instrument on August 5, 2025, the rock features a pointed peak and a pitted nodular texture that evokes the image of armor forged centuries ago. On Earth, similar nodular textures can form through chemical weathering, mineral precipitation, or even volcanic processes. Perseverance encountered a similar rock in March 2025.
"The target name for this rock is Horneflya, and it's distinguished not so much by its hat shape, but rather by the fact that it's composed almost entirely of spherules," David Agle, a spokesperson for the Perseverance team at NASA's Jet Propulsion Laboratory, told Space.com.
Scientists believe that in some rocks observed on Mars, these spherules form when groundwater passes through the pores of sedimentary rocks. However, they are unsure if all of them formed this way; the Perseverance science team will have a lot of work ahead analyzing more rocks to search for answers to this Martian geological mystery and other burning questions about the Red Planet.
The Mastcam-Z instrument, a pair of zoomable cameras on Perseverance's mast, allows scientists to capture high-resolution stereo images and detect unusual features like this spherule-covered "helmet" rock from a distance.
Perseverance has discovered a growing gallery of peculiarly shaped rocks, from doughnut-shaped meteorites to avocado pits. These types of images are examples of a phenomenon known as pareidolia, which describes the human brain's tendency to impose a familiar pattern on otherwise random visual data, whether it's a face in the clouds, a rabbit on the moon, or a medieval helmet on the Martian surface.
Features like this help scientists reconstruct the Red Planet's environmental history, showing how wind, water, and internal processes may have sculpted the landscape over billions of years.
Perseverance is currently exploring the northern rim of Jezero Crater, having successfully completed a challenging ascent of the ridge known as "Lookout Hill" late last year.
