"Mysterious Geometric Shapes Discovered Underground on Mars"
The Chinese rover Zhurong has discovered 16 buried polygonal structures beneath the surface of Mars in the Utopia Planitia region, suggesting a past influenced by freeze-thaw cycles. This finding, revealed by radar technology and published in Nature Astronomy, indicates that early Mars had a varied atmosphere capable of supporting such thermal processes. The structures, found 35 meters underground and extending horizontally for 1.9 kilometers, are not formed by lava but by sediment and thermal contraction cracking, hinting at a high obliquity of early Mars and significant paleoclimatic changes.