Introduction To Temehu Map Collection

 

Libya Maps:

Although Libyan law stipulates that Sahara travellers must be accompanied by a local desert expert, one still needs to use specialist maps and GPS devices, as none of these local experts knows all (or even a fraction) of the locations of   prehistoric rock art sites in the Sahara. In fact, even the best map in the market only features a rough guide to the locations of a tiny selection of the hundreds of thousands of cave drawings and rock engravings scattered across the desert; and therefore complete maps of the Sahara are yet to be produced. Maybe Google one day will fulfil the dream, as cataloguing the world's knowledge apparently is their goal. 

Our Libya map project was therefore established to collect maps, resources, links and information about navigation in the Sahara and GPS locations of  its rock art, and make them available free of charge to our visitors. There are a number of GPS websites currently attempting to build a global database of GPS coordinates, based on public contributions. Hopefully, we will build a small list of the best resources available in the Internet, some of which offer free GPS maps for personal use.

Our current collection so far includes a number of maps originally produced by the US Army Map Service and used here courtesy of the University of Texas Libraries at Austin; which although are not as detailed as, say, EWP's Jabel Acacus Map, they still nonetheless show the main features of the landscape, tracks and (of particular importance) the old local names, some of which have now disappeared from memory, as well as they cover a large area of Libya. We have also customised a number of Google maps, which can be used to zoom on any part of Libya and start your adventure right away. Google maps are very easy to use and have been used world wide to discover a number of new features, craters and sites. Some of our interactive Google maps have various layers to show the main archaeological and tourist sites in Libya, Panoramio photos from all over Libya, Wikipedia articles (along a host of misplaced markers from Honolulu and Congo-Brazzaville), distance calculator (which calculates distance between any two sites in the world), and coordinates calculator, which gives the coordinates of any place on earth simply by one click. However, we will be adding to our map collection as we find more information and maps available from the public domain. We have also linked to an excellent interactive Gazetteer database by the American National Geospatial-Intelligence Agency (see details below).

 

What is a topographic map?

Topographic maps show the shape and the main features of the land. The topography of any given area is shown by contours or brown lines representing different elevations:

• thick brown lines (Index Contours) define the actual feature and give its height.
• thin brown lines (Interval Contour) give the variation in elevation: very close lines mean steep slopes, lines with large gaps indicate gradual slopes.

 

 

 

What is scale?

It is the ratio representing the relation between a distance on a map and its corresponding distance on the land. For instances, a scale of 1:100,000 means that 1 unit on the map is equal to 100,000 identical units on the land. Use the link to Scale Calculator (see below) to find the actual value of any scale unit.

 

 

 

Map Scale Calculator:

Scale Calculator:
http://www.beg.utexas.edu/GIS/tools/scale2.htm

Using the tool available at the above link, you can calculate the actual value of any scale unit by typing only the representative fraction of your map: for example: if the map scale is 1:100,000, enter 100000 in the box provided.

To make things easier we have used the tool with various representative fractions to produce the following values of units:

 

1000
5,000
10,000
15,000
25,000
50,000
100,000
125,000
150,000
175,000
200,000
500,000
1,000,000
1250,000
1,500,000
1,750,000
2,000,000
2,250,000
2,500,000
2,750,000
3,000,000

= 0.015  miles per inch
= 0.078  miles per inch
= 0.157  miles per inch
= 0.236  miles per inch
= 0.394  miles per inch
= 0.789  miles per inch
= 1.578  miles per inch
= 1.972  miles per inch
= 2.367  miles per inch
= 2.761  miles per inch
= 3.156  miles per inch
= 7.891  miles per inch
= 15.78  miles per inch
= 19.72  miles per inch
= 23.67  miles per inch
= 27.61  miles per inch
= 31.56  miles per inch
= 35.51  miles per inch
= 39.45  miles per inch
= 43.40  miles per inch
= 47.34  miles per inch

Scale Values & Location of Prime Meridians

http://www.kb.nl/skd/skd/mathemat.html

Mathematical data for bibliographic descriptions of cartographic materials and spatial data

 

Navigation:

 

Using Map & Compass:
http://egsc.usgs.gov/isb/pubs/factsheets/fs03501.html

This guide provides detailed instructions for how to use a map and a compass to find your way around and determine the direction from one point on the map to another.

 

The Royal Institute of Navigation (RIN):
http://www.rin.org.uk/

"The Royal Institute of Navigation (RIN) is a learned society with charitable status. Formed in 1947, its aims have always been threefold: To unite all those with a professional or personal interest in any aspect of navigation in one unique body; To further the development of navigation in every sphere; And to increase public awareness of the art and science of navigation." http://www.rin.org.uk/

 

Recommended Commercial Maps of Libya:

 

 

Jabel Acacus - Tourist Map & Guide (1:100,000)
Publisher: EWP
www.ewpnet.com
UK supplier: West Col Productions, Reading, +44 01491-681284.

 

Libya Road Map (1:1,750,000)
Publisher: Gizi Map
www.gizimap.hu

 

Sahara & Environs (1:2,200,000)
Publisher: International Travel Maps.
www.itmb.com

 

Africa North & West (1:4,000,000)
Map Number: 953
Publisher: Michelin
www.michelintravel.com

 

 

GeoNames

GeoNames is an online geographical database of Latitude and Longitude coordinates of geographical places from any country in the world. The database is licensed under the Creative Commons Attribution 3.0 License, and currently includes over eight million placenames that are available for download free of charge, from: http://www.geonames.org/

 

http://www.geonames.org/

 

 

 

NGA: Geonames Search - OGC Viewer:

The American National Geospatial-Intelligence Agency Gazetteer Database:
http://geonames.nga.mil/ggmaviewer/MainFrameSet.asp

The term geospatial intelligence implies collecting information via mapping, charting and geodesy, and then evaluating the data to describe the actual physical features and their geographically-related activities on the ground. A Gazetteer is a database or a list of geographic place names and their longitudes and latitudes. The above link leads to an interactive database on which you can click the desired location to display its coordinates and find its local name(s). The geonames features will be displayed only when the scale is approximately 1: 2,000,000 or larger, so if names do not appear, just keep zooming in until you see them.

 

 

The World of The Landsat Satellites & Their View of The Earth:

The Landsat's mission is to collect, archive, and distribute data of all the Earth's land surface.
http://zulu.ssc.nasa.gov/mrsid/mrsid.pl

The first Landsat was launched on July 23, 1972, to initiate a new era of Earth observation from space for non-military purposes. The information collected  is now the standard for Earth observations. Landsat circa 1990/2000: click on the map to zoom in/out, or 'Select Image' from the menu below the map and click on the desired region on the map to display the image in a new window.

Note: the connection or links are secured (https://) and therefore the browser may not display them if it is set to reject expired or general certificates. You can either change your browser settings, or copy the URL of the image that pops up in a new window, paste it in a new tab or window, and then remove the letter /s/ from "https:// " and then hit enter.

 

Satellites:

Heavens-Above.com:
http://www.heavens-above.com/

"Real-time satellite, ISS, and Space Shuttle orbital pass information, maps, and star charts."

 

NASA's World Wind:

 

Download World Wind For Free, directly from http://worldwind.arc.nasa.gov/

NASA's open-source-program World Wind is similar to Google Earth - except in that it is free -   very handy indeed if you just want to publish an actual image in your website, rather than having to link to it via embeded script as you would with Google. The Landsat Global Mosaic (except for i-3 visible layer), Blue Marble, and the USGS raster maps and images are all Public Domain. (Please note that not all data provided by the add-ons is Public Domain). A lot easier to use too. The downloded program includes the required: .NET runtime, and the managed DirectX library. For user manual, please visit http://learn.arc.nasa.gov/worldwind/ .

 

NASA's Global Maps:

Follow the link (http://earthobservatory.nasa.gov/GlobalMaps/)
then click on any map to see the data moving through the year, month by month.

Solar & Lunar Data:

Sun & Moon Rise & Set, Eclipse Data, Phases of the Moon, Day & Night, Navigational Star Chart, and more:
http://www.usno.navy.mil/USNO/astronomical-applications/data-services

This link provides tools and tables for finding times for sunrises and sunsets, moonrises and moonsets, eclipse data, phases of the moon, hours of day and night in different locations, navigational star chart, and many more related data and calculators.

 

Moon Phase Images:
http://tycho.usno.navy.mil/vphase.html

View the phase of the moon for any date and time between the years 1800 and 2199 AD.

Please send comments & contribution to: map(at)temehu(dot)com