Curiosity Spots Ground-Level Sea of Small Polygonal Cracks on Mars

NASA's Curiosity rover images a field of small polygons in Gale Crater, about 4–8 cm across, likely mud cracks from ancient wet–dry cycles; these ground-level features differ from the much larger polygons seen by orbiters, and scientists caution that their exact formation is still uncertain, with possible links to early Martian climate during the Noachian–Hesperian transition.