The Cassini space-probe has recently completed a fly-by of Saturn and its moon Enceladus.  Early indications are that the moon contains pockets of liquid water only tens of metres below the surface.  The stunning image from the APOD site shows the “tiger-stripe” crevasses from which plumes of debris are being emitted.  The suspected cause: liquid water.  If the discovery pans out it will certainly be exciting, but it isn’t the first instance of liquid water detected outside of Earth.