tucson - The planet Mars may have much less water than imagined. On certain steep slopes you can see dark lines, a possible indication of underground water that drips down, but it seems that they are coming through something else.
The discolorations appear to be caused by avalanches of sand and dust. That is what American researchers say in the scientific journal Nature Geoscience.
The first dark lines were discovered in 2011. By now, thousands of lines have been seen on about fifty Marshalles. In the warm months they gradually sink down, in the winter they fade again.
All slopes with such lines are very steep. As soon as a slope becomes less steep, the lines stop. If water was the cause, the lines should also be visible on less steep slopes. 'We thought the lines might have come through liquid water, but they look more like dry sand. This indicates that Mars is pretty dry today, 'says lead researcher Colin Dundas. If that is correct, there is probably considerably less liquid water on Mars than expected. And that reduces the chance of minimal forms of life.
That does not mean that there is no water on Mars at all. Presumably there are some damp places here and there.