Astronomy is the oldest of the
sciences, and quite possibly the oldest
use of astronomy is navigating by the
stars. This craft dates back to
prehistoric times, likely having been
used to travel first over land and then
on water.
Celestial navigation uses the stars,
moon, sun, and horizon to calculate
position. Before navigational tools and
maps (and GPS!), it would have been
very useful over large expanses of
barren land or on the open ocean
where there were no landmarks.
Early travellers knew that the sun rose
in the east and set in the west and they
used that knowledge to guide their
travels. If they sailed into the rising
Sun, they knew they were heading east.
If they turned to the right, putting the
rising Sun on their left side, they knew
they were heading south.