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Apod posted this picture of Mars today: http://apod.nasa.gov/apod/ap161005.html
It may not look like much, but wow! This is much more obvious proof that there was once a lot of water on Mars than I have seen with my own eyes before. The top knot shows classic layered rock (mud stone?) as if deposited by floods. Then you have to wonder how long it took for this whole scene to be weathered down from a plain that the floods could have covered, to a much lower level with the butte still standing tall. What cut down the surrounding area? What eroded the butte and left the chunks of rock on the slopes, but not in the area surrounding the conical base? Water? The thin Martian atmosphere? Sand storms? Freeze-thaw of moisture or CO2? This looks like the same kind of hard-rock capped butte like you'd see on Earth.
It may not look like much, but wow! This is much more obvious proof that there was once a lot of water on Mars than I have seen with my own eyes before. The top knot shows classic layered rock (mud stone?) as if deposited by floods. Then you have to wonder how long it took for this whole scene to be weathered down from a plain that the floods could have covered, to a much lower level with the butte still standing tall. What cut down the surrounding area? What eroded the butte and left the chunks of rock on the slopes, but not in the area surrounding the conical base? Water? The thin Martian atmosphere? Sand storms? Freeze-thaw of moisture or CO2? This looks like the same kind of hard-rock capped butte like you'd see on Earth.