Mars Images Suggest Persistent Rivers Past

In a long-running debate over whether Mars ever had long-lasting rivers, the latest images supporting the “yes” side have been put forth. Pictures from NASA’s Mars Global Surveyor orbiter show eroded ancient deposits of transported sediment long since hardened into interweaving, curved ridges of layered rock. Scientists interpret some of the curves as traces of ancient “meanders” made in a sedimentary fan as flowing water changed its course over time.