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NASA's rover discovers bizarre skull-shaped structure on Mars

The Perseverance rover was going down a ridge when it spotted the unusual structure in a region where it wasn't supposed to be.

BY MAHALEKSHMI P

PUBLISHED APR 21, 2025

The Mars Rover explores the surface of the planet and records its findings about the hills and rock formations (Representative Cover Photo by piranka / Getty Images)

The mission to explore the surface of Mars to get better evidence of life on the planet has grown immensely in the last few years. In a recent development, NASA's Perseverance rover was driving through the Jezero Crater, which was believed to be a lake, when its camera caught an unusual object. A bizarre, skull-shaped elevation that was sitting on a slope where it wasn't expected to be. It has been dubbed “Skull Hill" and was discovered on April 11, as per NASA. The rock did not look native to the region. It was dark, angular, and contained small ditches, whereas the rest of the region was light-colored and dusty. It was likely that the rock originated elsewhere and was carried to the spot.

Angular and smooth surface of rocks are seen in an image taken by the panoramic camera on the Mars Exploration Rover Spirit on January 6, 2003. (Photo by NASA/Jet Propulsion Laboratory/ Cornell University via Getty Images)

The observation was made by the rover’s Mastcam-Z instrument, and experts termed the anomaly a ‘float’ rock. This was due to the hypothesis that the rock arrived at the location from elsewhere, a process termed as 'float.' The investigation into its original location has been underway, and such dark-colored floats were also found in the Port Anson region. The 'Skull Hill' resembled the colors of meteorites found in the Gale crater by the Curiosity rover. However, the analysis of SuperCam data from similar rocks did not align with a composition for a meteorite origin.

The European Space Agency released the early results from its Mars Express probe during a news conference on January 23, 2003. (Photo by ESA/DLR/FU Berlin (G. Neukum) via Getty Images)

The chemical composition of Gale’s meteorites contained high levels of iron and nickel, which were absent in the float. Another theory about the rock was that it could be igneous in nature, which would mark its origins to an impact crater or a rock formation. Margaret Deahn, a Ph.D. student at Purdue University working with NASA, hinted at the volcanic nature of the rock. This could be tested by analyzing the levels of iron and magnesium. These elements were forged when the lava or magma cooled down, which made them essential to an igneous rock.

The Navigation Cameras, or Navcams, aboard NASA’s Perseverance Mars rover captured this view of the rover’s deck on February 20, 2021. (Photo by NASA via Getty Images)

“Luckily for us, the rover has instruments that can measure the chemical composition of rocks on Mars,” Deahn stated, as per the New York Post. This suggested that various analyses were to be conducted to discern the nature of this unique feature. The color could also be attributed to dark colored minerals such as olivine, pyroxene, amphibole, and biotite present in them. The color was a focused aspect, as the composition of these darker-toned 'floats' could lead to its origins. Experts awaited further news from the rover about the rock’s composition and characteristics.

An illustrated image of the red planet in space, captured at an angle that shows the presence of sunlight (Photo by SCIEPRO / SCIENCE PHOTO LIBRARY / Getty Images)

The rock first caught the rover’s attention when it was journeying down the lower ‘Witch Hazel Hill’ on the Jezero crater rim. The rover stopped in its tracks to observe a boundary between a light and dark rock formation. This is not the first time a Martian rock was highlighted by the rover for its unique features. The rover had previously found a rock that could provide evidence of the presence of microbial life on Mars. It contained chemical signatures that indicated a past near a source of water. The rock was fine-grained and contained black, blue, or greenish color spots.

NASA's Perseverance (Mars 2020) rover uses its drill to core a rock sample and will store it for future missions, in the area known as Jezero crater on the planet Mars. (Photo illustration by NASA via Getty Images)

Such unique rocks on the Martian surface might be evidence of past life that existed on the red planet. Origins and characteristics of the unknown formations on the surface with varied signatures were essential to the Martian research. They provide evidence of the uniqueness that stood out from the red minerals and chemicals. Temperatures, natural events, climate change, water sources, and much more could be explained by these surface elements.