Where should we trench?
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The science team has been excited about the hypothesis that there
may have been recent standing water at the landing site. The team has
based this hypothesis on the observation of "mud cracks"
in Pancam images near the landing site (see sol 17 story). The science team
immediately began planning a "trenching" sol to trench into
the mud crack surface on sol 18. "These mud cracks are fascinating
features. Trenching through these features will be a challenging, but
scientifically exciting operation. If these features are mud cracks, then
there could have been recent standing water at the landing site,"
explained scientist Doug Ming.
"There are two hypotheses that we will be testing by trenching
into these mud crack features. First, the mud cracks may have formed
when clays settled out of standing water in a low area. The standing water
evaporated and the cracks were caused by the drying out of the clays.
The second hypothesis is that the polygonal shape of the mud cracks is
caused by the exfoliation or flaking of underlying sandstone,"
If the trench is easily excavated, it will indicate that the material is
mud or clay. However, if the material is hard and difficult
to trench then the material is probably sandstone that has flaked off of
the underlying bedrock.