To determine position in space, Apollo
astronauts located a specific star using
a single-power, wide-field telescope and
then took a fix using … a sextant! While this
instrument may not look like a traditional
sextant, the basic procedure is descended
from centuries-old methods used by navigators at sea and in the air.
OCTOBER | NOVEMBER 2013 BoatU.S. Magazine | 59
A coastal navigation chart from
1633 made by medieval European
mariners, based on their measurements, and embellished with the
remarkable images that had impressed them from their voyages.
An astrolabe measures the angle between the sun or a star and
the horizon. The Portuguese are credited with the perfection, if not
invention, of the instrument in the 15th century, their great era of
world exploration. This astrolabe was made in 1602.
A horary quadrant for taking time by the
sun. Other quadrants of similar design were
used to take angles of celestial bodies, like a
simpler version of the sextant.