This is a great example of why we need people on Mars. The rovers designers simply didn't anticipate it running into puddles of water, and thus it can't tell us anything about them, even that they definitely are puddles.

Astronauts encountering something utterly unforseen such as this would be able to get started on the science straight away, without waiting for another rover to be designed, built, and sent to Mars.

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"I worry that, especially as the Millennium edges nearer, pseudo-science and superstition will seem year by year more tempting, the siren song of unreason more sonorous and attractive." - Carl Sagan, 1995