Google Earth is a computer program that renders a 3D representation of Earth based on satellite imagery. The program maps the Earth by superimposing satellite images, aerial photography, GIS data onto a 3D globe, allowing users to see cities and landscapes from various angles. Users can explore the globe by using a keyboard or mouse; the program can be downloaded on a smartphone or tablet, using a touch screen or stylus to navigate. Users may use the program to add their own data using Keyhole Markup Language and upload them through various sources, such as forums or blogs. Google Earth is able to show various kinds of images overlaid on the surface of the earth and is a Web Map Service client. In addition to Earth navigation, Google Earth provides a series of other tools through the desktop application. Additional globes for the Moon and Mars are available, as well as a tool for viewing the night sky. A flight simulator game is included. Other features allow users to view photos from various places uploaded to Panoramio, information provided by Wikipedia on some locations, Street View imagery.
The web-based version of Google Earth includes Voyager, a feature that periodically adds in-program tours presented by scientists and documentarians. Google Earth has been viewed by some as a threat to privacy and national security, leading to the program being banned in multiple countries; some countries have requested that certain areas be obscured in Google's satellite images areas containing military facilities. The core technology behind Google Earth was developed at Intrinsic Graphics in the late 1990s. At the time, the company was developing 3D gaming software libraries; as a demo of their 3D software, they created a spinning globe that could be zoomed into, similar to the Powers of Ten film. The demo was popular, but the board of Intrinsic wanted to remain focused on gaming, so in 1999, they created Keyhole, Inc. headed by John Hanke. Keyhole developed a way to stream large databases of mapping data over the internet to client software, a key part of the technology, acquired patchworks of mapping data from governments and other sources.
The product, called "Keyhole EarthViewer", was sold on CDs for use in fields such as real estate, urban planning and intelligence. Despite making a number of capital deals with Nvidia and Sony, the small company was struggling to make payroll, employees were leaving. Fortunes for the company changed in early 2003 when CNN received a discount for the software in exchange for placing the Keyhole logo on-air whenever the map was used. Keyhole did not expect it would amount to more than brief 5 or 10 second prerecorded animation clips, but it was used extensively by Miles O'Brien live during the 2003 invasion of Iraq, allowing CNN and millions of viewers to follow the progress of the war in a way that had never been seen before. Public interest in the software exploded and Keyhole servers were not able to keep up with demand. Keyhole was soon contacted by the Central Intelligence Agency's venture capital firm, In-Q-Tel, the National Geospatial-Intelligence Agency, for use with defense mapping databases, which gave Keyhole a much-needed cash infusion.
Intrinsic Graphics was sold in 2003 to Vicarious Visions after its gaming libraries did not sell well, its core group of engineers and management transitioned to Keyhole with Hanke remaining at the head. At the time, Google was finding that over 25% of its searches were of a geospatial character, including searches for maps and directions. In October 2004, Google acquired Keyhole as part of a strategy to better serve its users. Google Earth's imagery is displayed on a digital globe, which displays the planet's surface using a single composited image from a far distance. After zooming in far enough, the imagery transitions into different imagery of the same area with finer detail, which varies in date and time from one area to the next; the imagery is retrieved from satellites or aircraft. Before the launch of NASA and the USGS's Landsat 8 satellite, Google relied on imagery from Landsat 7, which suffered from a hardware malfunction that left diagonal gaps in images. In 2013, Google used datamining to remedy the issue, providing what was described as a successor to the Blue Marble image of Earth, with a single large image of the entire planet.
This was achieved by combining multiple sets of imagery taken from Landsat 7 to eliminate clouds and diagonal gaps, creating a single "mosaic" image. Google now uses Landsat 8 to provide imagery with greater frequency. Imagery is hosted on Google's servers, which are contacted by the application when opened, requiring an Internet connection. Imagery resolution ranges from 15 meters of resolution to 15 centimeters. For much of the Earth, Google Earth uses digital elevation model data collected by NASA's Shuttle Radar Topography Mission; this creates the impression of three-dimensional terrain where the imagery is only two-dimensional. Every image created from Google Earth using satellite data provided by Google Earth is a copyrighted map. Any derivative from Google Earth is made from copyrighted data which, under United States Copyright Law, may not be used except under the licenses Google provides. Google allows non-commercial personal use of the images as long as copyrights and attributions are preserved.
By contrast, images created with NASA's globe software World Wind use The Blue Marble, Landsat, or USGS imagery, each of, in the public domain. In version 5.0, Google introduced Historical Imagery. Clicking the clock icon in the toolbar opens a time slider, which marks the tim
The Djurdjura or Jurjura Range is a mountain range of the Tell Atlas, part of the Atlas Mountain System. It is located in Algeria; the Djurdjura is a massif made up of two differentiated ranges, one in the north with the Haïzer and Akouker subranges and the other in the south. Its highest point, Lalla Khedidja known in Kabylian as Tamgut Aâlayen, has an elevation of 2,308 metres and it is located in the southern range. Other notable summits are the 2,305 m high Ich n'Timedouine, a peak located in the central area of the massif, highest point of the Akouker subrange. Adrar n'Hayzer, highest point of the Haïzer subrange, is a 2,164 m tall summit rising above Bouira and the high valley of Oued Dhous; the Thaletat is a 1,638 m high rocky mountain with a original shape located in Tizi Ouzou Province. Other notable features of the Djurdjura range are the 1,750 m high Tizi n'Tirourda mountain pass at the eastern end and the Kweryet, a 1500 m high mountain that rises to the north of the massif; this mountain gave its name to an ancient commune, Douar N'Kweryet, a commune that gathered certain villages of the Ouacifs and the Ouadhia.
The range had been known to the ancient Romans as the Iron Mountains. Famous mediaeval explorer Ibn Batuta went to Béjaïa through this mountain range, he was heading towards Tunis with a caravan on his Hajj journey and he traveled to Béjaïa from Mitidja, a plain near Algiers. The Zouaves of the French Army were first raised in Algeria in 1831 with one and two battalions recruited from the Zouaoua, a tribe of Berbers finding homes in the mountains of the Jurjura range; the Djurdjura National Park is a protected area within the range. This mountain range has a ski resort at Tikjda with places such as the Point De Vue Du Djurdjura, as well as the Gouffre de l’Akouker; the resort is located at a height of 1,478 m. Kabyles List of mountains in Algeria Tell Atlas Media related to Djurdjura at Wikimedia Commons Les montagnes d'atlas Persée - Notes de géographie physique algérienne
The Beni-Chougrane Range is a mountain range in the northwest of Algeria, part of the Atlas Mountain System. The mountains of Beni-Chougrane belong to the Tell Atlas chain located between the Plain of Habra-Sig in the north and the Plain of Ghriss in the south, they are characterized by a semi-arid terrain, which promotes erosion. The range's average altitude rises to 932 m in the vicinity of El Bordj. Several dams are located in the mountain range; as well as rich plains and major wadis such as El Hammam and Fergoug. The area is undergoing reforestation; the total area is 32 % of the area of Mascara wilaya. List of mountains in Algeria
The Tell Atlas is a mountain chain over 1,500 km in length, belonging to the Atlas mountain ranges in North Africa, stretching from Morocco, through Algeria to Tunisia. The ranges of this system have average elevations of about 1,500 m and form a natural barrier between the Mediterranean and the Sahara, its highest summit is the 2,308 m high Lalla Khedidja in the Jurjura Range. Several large cities such as the Algerian capital, with ~1,500,000 residents and Oran with ~770,000 residents lie at the base of the Tell Atlas; the Algerian city Constantine with 505,000 residents lies 80 km inland and directly in the mountains at 650 meters in elevation. A number of smaller towns and villages are situated within the Tell; the Tell Atlas runs parallel to the Mediterranean coast. Together with the Saharan Atlas to the south it forms the northernmost of two more or less parallel ranges which approach one another towards the east, remaining quite distinct from one another in Western Algeria and merging in Eastern Algeria.
At the western end, it ends at the Middle Atlas ranges in Morocco. The Tell Atlas are a distinct physiographic section of the larger Atlas Mountains province, which in turn is part of the larger African Alpine System physiographic division; the Tell Atlas and the Saharan Atlas form two natural barriers, the first against the Mediterranean and the second against the Sahara. Between them lies the valley of the Chelif and various lesser rivers. South of the Tell Atlas is the high plateau of the Hautes Plaines with level terrain where water collects during the wet season, forming large shallow salt lakes which become salt flats as they dry. Agriculture includes grazing of sheep and goats on grass in better-watered high plateau areas and some farming; the Chelif is a 725 km long river with headwaters in the Tell Atlas to its discharge into the Mediterranean. The Chelif is characterized by an fertile valley. Other noteworthy rivers having their sources in this range are the Seybouse River. Only seasonal streams are found flowing south from the Tell Atlas.
The Tell Atlas enjoys a typical Mediterranean climate, warm with dry summers and mild, rainy winters with snow at upper elevations. As a consequence, the northern slopes of the Tell Atlas are forested with the endemic Abies numidica, Atlas cedar and cork oak. In the summer a hot, dry wind, the Sirocco, blows north from the Sahara across the Tell Atlas, causing dusty, dry conditions along the northern coast of Africa. Despite the arid climate, some agriculture for barley and wheat farming is found in the Tell Atlas region; the Chiffa gorge is situated within the Tell Atlas. List of mountains in Algeria Saharan Atlas Media related to Tell Atlas at Wikimedia Commons Tell Atlas - The Great Soviet Encyclopedia
Lalla Khedidja or, is a mountain in Algeria. At 2,308 metres, it is the highest summit of a subrange of the Tell Atlas; this peak is located in the Akouker subrange of the eastern part of the Djurjura Range. It is the highest point of the Tell Atlas itself, in turn part of the wider Atlas Mountain System; the Lalla Khedidja is covered in snow in the winter. List of mountains in Algeria List of Ultras of Africa Media related to Lalla-Khadîdja at Wikimedia Commons "Lalla Khedidja, Algeria" on Peakbagger Grande Kabylie
A summit is a point on a surface, higher in elevation than all points adjacent to it. The topographic terms acme, apex and zenith are synonymous; the term top is used only for a mountain peak, located at some distance from the nearest point of higher elevation. For example, a big massive rock next to the main summit of a mountain is not considered a summit. Summits near a higher peak, with some prominence or isolation, but not reaching a certain cutoff value for the quantities, are considered subsummits of the higher peak, are considered part of the same mountain. A pyramidal peak is an exaggerated form produced by ice erosion of a mountain top. Summit may refer to the highest point along a line, trail, or route; the highest summit in the world is Everest with height of 8844.43 m above sea level. The first official ascent was made by Sir Edmund Hillary, they reached the mountain`s peak in 1953. Whether a highest point is classified as a summit, a sub peak or a separate mountain is subjective; the UIAA definition of a peak is.
Otherwise, it's a subpeak. In many parts of the western United States, the term summit refers to the highest point along a road, highway, or railroad. For example, the highest point along Interstate 80 in California is referred to as Donner Summit and the highest point on Interstate 5 is Siskiyou Mountain Summit. A summit climbing differs from the common mountaineering. Summit expedition requires: 1+ year of training, a good physical shape, a special gear. Although a huge part of climber’s stuff can be left and taken at the base camps or given to porters, there is a long list of personal equipment. In addition to common mountaineers’ gear, Summit climbers need to take Diamox and bottles of oxygen. There are special requirements for crampons, ice axe, rappel device, etc. Geoid Hill – Landform that extends above the surrounding terrain Nadir Summit accordance Peak finder Summit Climbing Gear List
Djanet is an oasis city, capital of Djanet District, in Illizi Province, southeast Algeria. It is located 412 km south of Illizi. According to the 2008 census it has a population of 14,655, up from 9,699 in 1998, an annual population growth rate of 4.3%. It is inhabited by the Kel Ajjer Tuareg people; the region of Djanet has been inhabited since Neolithic times. There were periods of ten thousand years at a time; the flora and fauna were luxuriant as is seen in the numerous rock paintings of Tassili n'Ajjer around Djanet. Populations of hunter-gatherers lived there. Djanet was founded in the Middle Ages by the Tuareg; the Ottoman Empire, which had a nominal authority over the Fezzan region, reinforced their presence in the area at the beginning of the 20th century in reaction to the colonization of Africa by the Europeans. Djanet, the nearby towns of Azelouaz, El Mihan and Eferi, lie in a valley carved by the intermittent river Oued Idjeriou through the southwest edge of the Tassili n'Ajjer mountain range and east of the Erg Admer sand dunes.
The Tadrart Rouge is located to the southeast and is a southern prolongation of the Libyan Tadrart Acacus. Due to the somewhat cooler air, higher humidity and somewhat higher rainfall in these areas, the nearby mountains support a greater amount and variety of wildlife than lower-lying areas in the Sahara, forms part of the West Saharan montane xeric woodlands ecosystem. Djanet itself lies at an altitude of 1,035 metres, but the mountains to the east and north reach as high as 1,905 metres. Djanet has a hot desert climate, with hot summers and mild winters; the city is dry throughout the year, with an annual average rainfall of just 14.6 millimetres and no month with an average of more than 3 millimetres. Djanet Inedbirene Airport is located about 50 kilometers south of the city center. 4.1% of the population has a tertiary education, another 19.8% has completed secondary education. The overall literacy rate is 85.6%, is 92.1% among males and 78.0% among females, all three rates being the highest for any commune in the province.
The commune is composed of 12 localities