|Why does the shadow of this volcano look like a triangle? The
Mount Teide volcano itself does not have the strictly that its
geometric shadow might suggest. The triangle shadow phenomena is
not unique to the Mt. Teide, though, and is seen from the tops
of other large mountains and volcanoes. A key reason for the
strange dark shape is that the observer is looking down the long
corridor of a sunset (or sunrise) shadow that extends to the
horizon. Even if the huge volcano was a perfect cube and the
resulting shadow was a long rectangular box, that box would
appear to taper off at its top as its shadow extended far into
the distance, just as parallel train tracks do. The above
spectacular image shows Pico Viejo crater in the foreground,
located on Tenerife in the Canary Islands of The nearly full
moon is seen nearby shortly after its total lunar eclipse last
month. Juan Carlos Casado