methods and tools used today
Navigation is what makes seafaring possible in open waters. Contemporary
navigation, as is easy to guess, has advanced greatly since instruments
as those described above were used. One could say that navigation
has grown into an important science over the ages.
Like any science, navigation has its foundation. The basics of
this particular science are: "dead reckoning" (determining
the location of the ship by means of its speed, distance, and
direction of travel; this is not a very accurate method of navigation
due to winds, currents, steering errors, that may interfere);
piloting (steering the ship with the help of navigational tools,
geographical landmarks, etc.); electronic navigation (probably
the most sophisticated and most accurate method which uses radio
signals and electronic equipment); celestial navigation (nowadays
navigation by the stars uses the same concepts as ancient navigation
tools, but with much more advanced accuracy).
a) Maps and Charts
"Morski Sviat" magazine,
c) Electronic devices
Electronic navigation is somewhat of a lifesaver in this day and
age. Keeping a constant radio connection with land and with other
vessels is essential to preventing collisions, escaping sea storms,
and sometimes determining the ship's location.
The radio was introduced to navigation in the early 1900s. The
Direction Finder (D/F) device, which was used back then, is now
probably the most widespread navigational instrument.
In a few words, here is how a D/F works. The ship connects via
radio with a static radio station whose location is known. The
antenna of the D/F radio receiver has a loop on top of it and
is highly sensitive to the signal it receives. When the loop's
axis points directly to the radio station, it will receive no
signal. If the loop's plane faces the radio station, it will receive
a strong signal. Thus by pointing to loop so it doesn't receive
any signal at all, a navigator knows in what direction is the
An automatic direction finder (ADF) is a more advanced version
of a D/F. It has a motor that turns the loop and keeps it in the
null position at all times (when no signal is received).
Another very common device used today is the radar. It obtains
information about objects, which are out of the range of vision.
Electronic equipment is used to record and analyze the behavior
of radio waves sent out from the vessel. Those waves, which do
not encounter obstacles, simply disperse. Those, which meet an
object, bounce back to the vessel that sent them and provide data
about the shape and position of objects in the area.
d) Nautical Astronomy
Celestial navigation is known to man from ancient times, ever
since stars and planets have been identified. The advantage of
this kind of navigation is that it allows travel in open waters.
Those voyages would have no limitations, if it weren't for the
only downside of nautical astronomy - poor visibility. Anything
from a fog to an ocean storm can prevent navigators from orienting
by the stars.
Time in celestial navigation is measured by the apparent movement
of the sun westward at 15 degrees longitude per hour. Hence the
time difference between two places on the face of the earth, located
at different longitudes.
Consequentially, accurate time is vital to navigators using nautical
maps and charts.