We 
 view the illuminated object
 and watch it go dark. 
 Everyone on one side of the
 Earth can see the Moon – so a given lunar eclipse
 is visible to many people.
 
  
 
 We view the illuminating object
 (the Sun) and see it blocked out. 
 Only a few people are in the
 right place to be in the shadow.
 It is “coincidence” that
 the umbra just barely reaches earth.