So I always see in the news that the curiosity rover or some nasa study of previous data discovered evidence of water like its actually news. Wasn't it shown a decade ago that there is conclusive evidence that lots of water existed on mars? I don't get why they're still spending so much time looking for water and doing analyses to confirm that water flowed on Mars. Its like spending time and money finding more evidence that gravity affects us. Can someone explain why nasa is wasting so much time and resources looking for more evidence of prehistoric water on mars? it makes no sense.