Free Astronomy Magazine November-December 2014

MOON cerns the whole of the more characteristic area of the visible side of our natural sat- ellite, and in particular, its more macroscopic structure, the Oceanus Procellarum (Ocean of Storms), a vast region of the Moon’s north-west quadrant characterized by low elevations and a relatively thin surface crust. It is sufficient to look at the Moon even just for a moment to notice those dark patches that our remote ancestors considered seas, but that today we know to be basaltic plains formed as a result of the surfacing of huge amounts of magma. The slightly rounded shape of the maria has for a long time led astronomers to be- lieve that all those structures were scars of A ll the maria of the visible hemisphere of the Moon and those close to the edge. The largest is the Oceanus Procellarum, whose borders overlap those of the adjacent maria. [Enrique Luque Cervigón] Below, 3 differ- ent ways of view- ing the Moon: in visible light (left); in topographic mode (centre), with the red indi- cating the highest mountains and the blue the low- est; in map format of the gravitation- al gradients asso- ciated with the surface conforma- tions. Clearly evi- dent is the seg- ments network that on a large scale forms a polygonal shape. [NASA/Colorado School of Mines/ MIT/JPL/GSFC]