Finding your way around. Getting from point A to point B.
is a field of study that focuses
on the process of
of a craft or vehicle from one place to another.
The field of navigation includes four general categories: land navigation,
, aeronautic navigation, and
. It is also
the term of art used for the specialized knowledge used by navigators to
perform navigation tasks. All navigational techniques involve locating the
navigator's position compared to known locations or
in a broader sense
, can refer to any skill or study that involves the
determination of position and direction. In this sense, navigation
includes orienteering and
is a certain place or abstract
in a portion of
where something is
located with respect to
of some region.
is a function of the
as well as the
awareness of time
, place and
Position and Momentum Space
is a line where something moves to that leads to a place
refers to the instruments used by
and pilots as tools of their
trade. The purpose of navigation is to ascertain the present position and
to determine the speed, direction etc. to arrive at the port or point of
History of Navigation
is a group of sports that requires navigational skills
using a map
to navigate from point to point in diverse and
usually unfamiliar terrain, and normally moving at speed. Participants are
given a topographical map, usually a specially prepared orienteering map,
which they use to find control points. Originally a training exercise in
land navigation for military officers, orienteering has developed many
variations. Among these, the oldest and the most popular is foot
orienteering. For the purposes of this article, foot orienteering serves
as a point of departure for discussion of all other variations, but almost
any sport that involves racing against a clock and requires navigation
with a map is a type of orienteering.
Map & Compass Handbook
outdoor recreational activity, in which participants use a Global
Positioning System (GPS)
receiver or mobile device and other navigational
techniques to hide and seek containers, called "geocaches" or "caches", at
specific locations marked by coordinates all over the world.
Geographic Information System
is a system designed to capture, store,
manipulate, analyze, manage, and present spatial or geographic data. The
is sometimes used for
geographic information science (GIScience) to refer to the academic
discipline that studies geographic information systems and is a large
domain within the broader academic discipline of geoinformatics. What goes
beyond a GIS is a spatial data infrastructure, a concept that has no such restrictive boundaries.
is a system that uses satellites
autonomous geo-spatial positioning. It allows small electronic receivers
to determine their location (longitude, latitude, and altitude/elevation)
to high precision (within a few metres) using time signals transmitted
along a line of sight by radio
from satellites. The system can be used for
providing position, navigation or for tracking the position of something
fitted with a receiver (satellite tracking). The signals also allow the
to calculate the current local time to high precision,
which allows time synchronisation. Satnav systems operate independently of
any telephonic or internet reception, though these technologies can
enhance the usefulness of the positioning information generated.
is a space-based
radio navigation system
the United States government and operated by the United States Air Force.
It is a global navigation satellite system that provides geolocation and
time information to a GPS receiver anywhere
on or near the Earth where there is an unobstructed line of sight to four
or more GPS satellites
is a satellite used by the NAVSTAR Global Positioning System (GPS). The
first satellite in the system, Navstar 1, was launched February 22, 1978.
The GPS satellite constellation is operated by the 50th Space Wing of the
United States Air Force. The GPS satellites circle the Earth at an
altitude of about 20,000 km (12,427 miles) and complete two full orbits
is a device that is capable of receiving information
from GPS satellites and then to calculate the device's geographical
position. Using suitable software, the device may display the position on
a map, and it may offer directions. The Global Positioning System (GPS)
uses a global navigation satellite system (GNSS) made up of a network of a
minimum of 24, but currently 30, satellites placed into orbit by the U.S.
Department of Defense.
positioning is a satellite navigation technique used to
enhance the precision of position data derived from satellite-based
positioning systems (global navigation satellite systems, GNSS) such as
GPS, GLONASS, Galileo, and BeiDou. It uses measurements of the phase of
the signal's carrier wave in addition to the information content of the
signal, and relies on a single reference station or interpolated virtual
station to provide real-time corrections, providing up to centimetre-level
accuracy. With reference to GPS in particular, the system is commonly
referred to as Carrier-Phase Enhancement, or CPGPS. It has applications in
land survey, hydrographic survey, and in consumer unmanned aerial vehicle
or estimation of the real-world geographic location of
an object, such as a radar source, mobile phone, or Internet-connected
computer terminal. In its simplest form geolocation involves the
generation of a set of geographic coordinates and is closely related to
the use of positioning systems, but its usefulness is enhanced by the use
of these coordinates to determine a meaningful location, such as a street
address. For either geolocating or positioning, the locating engine often
uses radio frequency (RF) location methods, for example Time Difference Of
Arrival (TDOA) for precision. TDOA systems often utilise mapping displays
or other geographic information system. When a GPS signal is unavailable,
geolocation applications can use information from cell towers to
triangulate the approximate position, a method that is not as accurate as
GPS but has greatly improved in recent years. This is in contrast to
earlier radiolocation technologies, for example Direction Finding where a
line of bearing to a transmitter is achieved as part of the process.
is the orientation, angular position, or attitude of an object such as a
line, plane or rigid body is part of the description of how it is placed
in the space it is in. Namely, it is the imaginary rotation that is needed
to move the object from a reference placement to its current placement. A
rotation may not be enough to reach the current placement. It may be
necessary to add an imaginary translation, called the object's location
(or position, or linear position). The location and orientation together
fully describe how the object is placed in space. The above-mentioned
imaginary rotation and translation may be thought to occur in any order,
as the orientation of an object does not change when it translates, and
its location does not change when it rotates.
is the process of calculating one's current position by using a
previously determined position, or fix, and advancing that position based
upon known or estimated speeds over elapsed time and course. The
corresponding term in biology, used to describe the processes by which
animals update their estimates of position or heading, is path
integration. Drift is the angle between the heading of the airplane and
the desired track. A is the last known position (fix, usually shown with a
circle). B is the air position (usually shown with a plus sign). C is the
DR position (usually shown with a triangle). Dead reckoning is subject to
cumulative errors. Advances in navigational aids that give accurate
information on position, in particular satellite navigation using the
Global Positioning System, have made simple dead reckoning by humans
obsolete for most purposes. However, inertial navigation systems, which
provide very accurate directional information, use dead reckoning and are
very widely applied. By analogy with their navigational use, the words
dead reckoning are also used to mean the process of estimating the value
of any variable quantity by using an earlier value and adding whatever
changes have occurred in the meantime. Often, this usage implies that the
changes are not known accurately. The earlier value and the changes may be
measured or calculated quantities. There is speculation on the origin of
the term, but no reliable information.
. No absolute direction corresponds to any of the relative directions.
This is a consequence of the
laws of physics
: nature, loosely speaking, behaves the same no matter what
direction one moves. As demonstrated by the Michelson-Morley null result,
there is no absolute inertial
frame of reference
There are definite relationships between the
Left and right, forward and backward, and up and down are three pairs of
complementary directions, each pair orthogonal to both of the others.
Relative directions are also known as egocentric coordinates. Aborigines
speak in directions of north, south, east and west instead of left, right,
back or forward.
encompasses all of the ways in which people (and animals) orient
themselves in physical space and navigate from place to place. The basic
process of wayfinding involves four stages: Orientation is the attempt to
determine one's location, in relation to objects that may be nearby and
the desired destination. Route decision is the selection of a course of
direction to the destination. Route monitoring is checking to make sure
that the selected route is heading towards the destination. Destination
recognition is when the destination is recognized.
is a person's point-of-view perception of their area of
interaction. Although this kind of subject matter would seem most likely
to be studied by fields in the social sciences, this particular subject is
most often studied by modern day geographers. They study it to determine
subjective qualities from the public such as personal preference and
practical uses of
like driving directions. Mass media also have
a virtually direct effect on a person's mental map of the geographical
world. The perceived geographical dimensions
of a foreign nation (relative
to one's own nation) may often be heavily influenced by the amount of time
and relative news coverage that the news media may spend covering news
events from that foreign region. For instance, a person might perceive a
small island to be nearly the size of a continent, merely based on the
amount of news coverage that he or she is exposed to on a regular basis.
In psychology, the term names the information maintained in the mind of an
organism by means of which it may plan activities, select routes over
previously traveled territories, etc. The rapid traversal of a familiar
maze depends on this kind of mental map if scents or other markers laid
down by the subject are eliminated before the maze is re-run.
Navigating based solely on surrounding Smells
. The brain can form a
virtual landscape map of its surroundings based solely on
is a field of science devoted to the study of the
features, the inhabitants, and the phenomena of Earth.
Smarty Pins with Google
is the study of the shape and features of the
surface of the Earth
other observable astronomical objects including planets, moons, and
asteroids. The topography of an area could refer to the surface shapes and
features themselves, or a description (especially their depiction in
is the inability to orient oneself in one's
surroundings as a result of focal
disability may result from the inability to make use of selective spatial
information (e.g., environmental landmarks) or to orient by means of
specific cognitive strategies such as the ability to form a mental
representation of the environment, also known as a cognitive map. It may
be part of a syndrome known as visuospatial dysgnosia.
is defined based on the context in which it is used (aviation, geometry,
geographical survey, sport, atmospheric pressure, and many more). As a
general definition, altitude is a distance measurement, usually in the
vertical or "up" direction, between a reference datum and a point or
object. The reference datum also often varies according to the context.
Although the term altitude is commonly used to mean the height above sea
level of a location, in geography the term elevation is often preferred
for this usage. Vertical distance measurements in the "down" direction are
commonly referred to as depth.
symbolic depiction emphasizing relationships between elements of some
space, such as objects, regions, or themes. Many maps are static, fixed to
paper or some other durable medium, while others are dynamic or
interactive. Although most commonly used to depict geography, maps may
represent any space, real or imagined, without regard to context or scale,
such as in brain mapping, DNA mapping, or computer network topology
mapping. The space being mapped may be two dimensional, such as the
surface of the earth, three dimensional, such as the interior of the
earth, or even more abstract spaces of any dimension, such as arise in
modeling phenomena having many independent variables.
is a type of map characterized by large-scale detail
and quantitative representation of relief, usually using contour lines,
but historically using a variety of methods. Traditional definitions
require a topographic map to show both natural and man-made features.
is a map used to aid in navigation and can symbolize an
assorted amount of information of a particular area or contain only a
single representation of the data it represents.
is a map that primarily displays roads and transport links rather than
natural geographical information. It is a type of navigational map that
commonly includes political boundaries and labels, making it also a type
of political map. In addition to roads and boundaries, road maps often
include points of interest, such as prominent businesses or buildings,
tourism sites, parks and recreational facilities, hotels and restaurants,
as well as airports and train stations. A road map may also document
non-automotive transit routes, although often these are found only on
is a special-purpose map made to show geological
features. Rock units or geologic strata are shown by color or symbols to
indicate where they are exposed at the surface. Bedding planes and
structural features such as faults, folds, foliations, and lineations are
shown with strike and dip or trend and plunge symbols which give these
features' three-dimensional orientations.
The genius of the London Tube Map: Michael Bierut
(video and text)
instrument used for navigation and orientation that shows direction
relative to the geographic cardinal directions (or points). Usually, a
diagram called a compass rose shows the directions north, south, east, and
west on the compass face as abbreviated initials. When the compass is
used, the rose can be aligned with the corresponding geographic
directions; for example, the "N" mark on the rose points northward.
Compasses often display markings for angles in degrees in addition to (or
sometimes instead of) the rose. North corresponds to 0°, and the angles
increase clockwise, so east is 90° degrees, south is 180°, and west is
270°. These numbers allow the compass to show azimuths or bearings, which
are commonly stated in this notation.
Animals use Earths
Magnetism to Navigate
are the instruments in the cockpit of an aircraft
that provide the pilot with information about the flight situation of that
aircraft, such as altitude, airspeed
. They improve safety by allowing the pilot to fly the
aircraft in level flight, and make turns, without a reference outside the
aircraft such as the horizon. Visual flight rules (VFR) require an
airspeed indicator, an altimeter, and a compass or other suitable magnetic
direction indicator. Instrument flight rules (IFR) additionally require a
gyroscopic pitch-bank (artificial horizon), direction (directional gyro)
and rate of turn indicator, plus a slip-skid indicator, adjustable
altimeter, and a clock. Flight into Instrument meteorological conditions
(IMC) require radio navigation instruments for precise takeoffs and
Which way is North ?
How to tell which way is North using the Sun
The Directions below are for the Northern Hemisphere.
In the Southern Hemisphere it's the Opposite (North is now South)
Place a 3' long stick in the ground firmly
Mark the end of the shadow from the 3' long stick with a smaller stick.
Now wait around 15 minutes.
Use another small stick to mark where the end of the shadow is now.
Lay another stick on the ground so that it touches both small sticks.
Place your left foot towards the first small stick marker.
Place your right foot towards the second small stick marker.
With your body facing the 2 small sticks used to mark the ends of the shadow you are now facing north. Your Right is east,
your left is west and behind you is south.
At 12 noon your shadow will be facing North in the Northern Hemisphere
Finding North without a compass #1
Another way using the Sun to tell Direction:
If you have a digital watch with no hour & minute hand then just replicate a
watch with sticks to match the time on your digital watch.
Point the hour hand at the sun.
Half way between the hour hand and 12 noon will be do south.
(If you are in the southern Hemisphere the it would be north)
When facing north, your Right is East, your Left is West.
At Night know how to use the Stars and Moon to tell North,
but of course it's always best to carry a Compass.
The North Star is the last star in the handle of the Little
You can also find the North Star by using the Big
The outermost stars of the cup of the Big Dipper
forms a straight line that always "points" to the North Star or Polaris.
Find True North Without a Compass
Tell Time Without a Clock
Hiking and Trails Information
is the ancient science of position fixing that
enables a navigator to transition through a
without having to rely
on estimated calculations, or dead reckoning, to know their position.
Celestial navigation uses "sights," or angular measurements taken between
a celestial body (the sun, the moon, a planet or a
) and the visible
horizon. The sun
is most commonly used, but navigators can also use the
moon, a planet, Polaris, or one of 57 other navigational stars whose
coordinates are tabulated in the nautical almanac and air almanacs.
Celestial navigation is the use of angular measurements (sights) between
celestial bodies and the visible horizon to locate one's position on the
globe, on land as well as at sea. At a given time, any celestial body is
located directly over one point on the Earth's surface. The latitude and
longitude of that point is known as the celestial body’s
(GP), the location of
which can be determined from tables in the Nautical or Air Almanac for
that year. The measured angle between the celestial body and the visible
horizon is directly related to the distance between the celestial body's
GP and the observer's position. After some computations, referred to as
sight reduction, this measurement is used to plot a
line of position
(LOP) on a
navigational chart or plotting work sheet, the observer's position being
somewhere on that line. (The LOP is actually a short segment of a very
large circle on the earth which surrounds the GP of the observed celestial
body. An observer located anywhere on the circumference of this circle on
the earth, measuring the angle of the same celestial body above the
horizon at that instant of time, would observe that body to be at the same
angle above the horizon.) Sights on two celestial bodies give two such
lines on the chart, intersecting at the observer's position (actually, the
two circles would result in two points of intersection arising from sights
on two stars, but one can be discarded since it will be
far from the estimated position. Most
navigators will use sights of three to five stars, if they're available,
since that will result in only one common intersection and minimize the
chance for error. That premise is the basis for the most commonly used
method of celestial navigation, and is referred to as the
'. There are several other methods of celestial
navigation which will also provide position finding using sextant
observations, such as the noon sight, and the more archaic lunar distance
method. Joshua Slocum used the lunar distance
method during the first ever
recorded single-handed circumnavigation of the world. Unlike the
altitude-intercept method, the noon sight and lunar distance methods do
not require accurate knowledge of time. The altitude-intercept method of
celestial navigation requires that the observer know exact
Greenwich Mean Time
(GMT) at the moment of
his observation of the celestial body, to the second—since every four
seconds that the time source (commonly a chronometer or in aircraft, an
accurate "hack watch") is in error, the position will be off by
approximately one nautical mile.
Galactic Coordinate System
is a celestial coordinate system
in spherical coordinates, with the Sun as its center, the primary
direction aligned with the approximate center of the Milky Way galaxy, and
the fundamental plane approximately in the galactic plane. It uses the
right-handed convention, meaning that coordinates are positive toward the
north and toward the east in the fundamental plane.
octant is a tool used to calculate
sea by measuring the angle between the sun and the horizon. It uses a
small mirror to align the two celestial bodies together. The octant has an
arc of 45° that measures angles of 90o.
is a timepiece that is precise and accurate enough
to be used as a portable time standard; it can therefore be used to
of celestial navigation.
Why we see the same Stars
? (star charts)
in the sky is defined by a pair of angles relative to the
celestial equator: declination (d) and right ascension (a). While d is
given in degrees (from +90° at the celestial north pole to -90° at the
south pole), a is usually given in hours (0 ... 24h). This is due to the
observation technique of star transits, which cross the field of view of
telescope eyepieces because of Earth's rotation. The observation
techniques are topics of positional astronomy and of astrogeodesy. Ideally
coordinate system a, d refers to an inertial frame of
reference; the 3rd coordinate is the star distance, which is normally used
as an attribute of the individual star. Star positions are changing in
time, caused by precession and nutation – slow tilts of Earth's axis with
rates of 50 arcseconds and 2 arcseconds respectively, per year; aberration
and parallax – effects of Earth's orbit around the Sun; proper motion of
the individual stars. The effects 1 and 2 are considered by so-called mean
places of stars, contrary to their apparent places as seen from the moving
Earth. Usually the mean places refer to a special epoch, e.g. 1950.0 or
2000.0. The 3rd effect has to be handled individually. The star positions
a, d are compiled in several star catalogues of different volume and
accuracy. Absolute and very precise coordinates of 1000-3000 stars are
collected in Fundamental catalogues, starting with the FK (Berlin ~1890)
up to the modern FK6. Relative coordinates of numerous stars are collected
in catalogues like the Bonner Durchmusterung (Germany 1852-1862, 200.000
rough positions), the SAO catalogue (USA 1966, 250.000 astrometric stars)
or the Hipparcos and Tycho catalogue (110.000 and 2 million stars by space
astrometry). Space Travel
is the equatorial coordinate specifying the angle,
measured eastward along the celestial equator, from the vernal equinox to
the intersection of the hour circle that passes through an object in the
sky; usually expressed in hours and minutes and seconds; used with
declination to specify positions on the celestial sphere.
is the angular distance of a celestial body north or to
the south of the celestial equator; expressed in degrees; used with right
ascension to specify positions on the celestial sphere.
A minute of arc
, arcminute (arcmin), arc minute, or minute arc is a unit of angular measurement equal to 1/60th of one
is often specified in
Astronomical Units (AU)--an AU is the
average distance from the Earth
to the Sun = 149,597,870 kilometers (92,955,730 miles). For objects
outside the solar system, the light year (ly) is often used. This is the
distance light travels in a year,
One light year
is equal to 63,240 AU.
is a unit of length
roughly the distance from Earth to the Sun. However, that distance varies
as Earth orbits the Sun, from a maximum (aphelion) to a minimum
(perihelion) and back again once a year. Originally conceived as the
average of Earth's aphelion and perihelion, it is now defined as exactly
149597870700 metres (about 150 million kilometres, or 93 million miles).
The astronomical unit is used primarily as a convenient
distances within the Solar System or around other stars. However, it is
also a fundamental component in the definition of another unit of
astronomical length, the parsec.
Astronomical System of Units
is a system of measurement developed for
use in astronomy
is the tracing and measurement of a series or network of
triangles in order to determine the distances and relative positions of
points spread over a territory or region, especially by measuring the
length of one side of each triangle and deducing its angles and the
length of the other two sides by observation from this baseline. In
trigonometry and geometry,
is the process of determining the location of a point by
forming triangles to it from known points.
is a method of establishing geodetic
relationships between points on the earth’s surface by simultaneous
observations of the moon, high-altitude balloons with light sources, or
artificial earth satellites from these points.
, typically made of transparent plastic or
glass, for measuring angles
. Most protractors measure angles in degrees
(°). Radian-scale protractors measure angles in radians. Most protractors
are divided into 180 equal parts. They are used for a variety of
mechanical and engineering
applications, but perhaps the most common use is in geometry lessons in
schools. Some protractors are simple half-discs. More advanced
protractors, such as the bevel protractor, have one or two swinging arms,
which can be used to help measure the angle.
"Men take shortcuts, while women follow well-known routes."