ScuttleMonkey from the best-discoveries-by-accident dept.
The rover Spirit has been dragging one wheel around the surface of Mars for some time. One of the resulting gouges revealed a mineral deposit which was probably caused by a hydrothermal vent. This implies a large amount of water was present when the vent was active.
We will have solar energy as soon as the utility companies solve one technical
problem -- how to run a sunbeam through a meter.