GPS Tracking Mysteries: What Is Longitude?

in Gps

The Global Positioning System (GPS) is a satellite-based navigation system made up of a network of 24 satellites placed into orbit by the U.S. Department of Defense.

GPS was originally intended for military applications, but in the 1980s, the government made the system available for civilian use.

GPS original name is NAVSTAR-GPS. GPS works in any weather conditions, anywhere in the world, 24 hours a day. There are no subscription fees or setup charges to use GPS.

Data logger is any device that stores data so consequently GPS data logger will store GPS data.

Data loggers are an example of passive trackers. The GPS Data Logger is a small, robust unit that records position data from a GPS.

It is a convenient, economical alternative to using a laptop computer or PDA, especially on long road, 4WD and motorcycle trips. Following parameters can be retrieved from a GPS data-logger


The information can be exported in excel sheets and software like Google maps etc.

So let's take a look at Longitude:

Longitude is defined in terms of meridians, which are half-circles running from pole to pole.

A reference meridian, called the prime meridian, is selected, and this forms the reference by which longitudes are defined.

On the earth, the prime meridian passes through Greenwich, England; for this reason it is also called the Greenwich meridian . The longitude of a point P on the surface is defined as the angle that the plane containing the meridian passing through P subtends with respect to the plane containing the prime meridian.

If P is to the east of the prime meridian, the longitude is positive; if P is to the west of the prime meridian, the longitude is negative.

Longitude angles can range up to +180 degrees (180 degrees east), and down to -180 degrees (180 degrees west). The +180 and -180 degree longitude meridians coincide directly opposite the prime meridian.

Let's read us some longitude and latitude, shall we? Here's an example of a precise point on the earth represented as longitude and latitude.

Let's geocode the address of favorite locally-owned and operated taco shop, Roscoe's Tacos! Roscoe's Tacos is located at

642 S Madison Ave.
Greenwood IN 46142

Now that same address written in the form of longitude and latitude looks like this:

39°36'24"N, 86°6'26"W
(39.606759, -86.107287)
39 ° 36.4055', -86 ° 6.4372'
The weird symbols stand for different measurements of either degrees, minutes or seconds. So if you want to speak the longitude and latitude coordinates out loud for good old Roscoe's Tacos (39°36'24"N, -86°6'26"W) you would say, "Roscoe's Tacos is located at 39 degrees, 36 minutes, and 24 seconds north of the equator and 86 degrees, six minutes and 26 seconds west of the meridian passing through Greenwich, England).

GPS tracking system is one of the most remarkable effects of the technological revolution that has occurred over the last two decade. To keep up pace with this fast changing technology you have to have one of these!

Get the bestGPS tracking tools online. Visit Chinavasion or paste this link into your browser:

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Rose Li has 7169 articles online and 9 fans

Rose Li is the PR Manager for Chinavasion, China's premier dropshipper for wholesale consumer electronics

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GPS Tracking Mysteries: What Is Longitude?

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This article was published on 2010/09/27