Imaginary lines on the Earth

map give information on relief
map give information on political organization
indicates how many times the Earth has been reduced.
and are lines which stablishthe exact location on places
are semicircles which go from one to the .
The meridian or meridian is the point of reference for the other
are circles which are to the meridians
is measured by using the which star at the Equator
is measured by using the which star at the prime meridian