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Equatorial Plasma Bubble
Equatorial plasma bubbles are an ionospheric phenomenon near the Earth's geomagnetic equator at night time. They affect radio waves by causing varying delays. They degrade the performance of GPS The Global Positioning System (GPS), originally Navstar GPS, is a Radionavigation-satellite service, satellite-based radionavigation system owned by the United States government and operated by the United States Space Force. It is one of t .... Different times of the year and locations have different frequencies of occurrence. In Northern Australia, the most common times are February to April and August to October, when a plasma bubble is expected every night. Plasma bubbles have dimensions around 100 km. Plasma bubbles form after dark when the sun stops ionising the ionosphere. The ions recombine, forming a lower density layer. This layer can rise through the more ionized layers above via convection, which makes a plasma bubble. The bubbles are turbulent with irregular edges ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ionospheric
The ionosphere () is the ionized part of the upper atmosphere of Earth, from about to above sea level, a region that includes the thermosphere and parts of the mesosphere and exosphere. The ionosphere is ionized by solar radiation. It plays an important role in atmospheric electricity and forms the inner edge of the magnetosphere. It has practical importance because, among other functions, it influences radio propagation to distant places on Earth. History of discovery As early as 1839, the German mathematician and physicist Carl Friedrich Gauss postulated that an electrically conducting region of the atmosphere could account for observed variations of Earth's magnetic field. Sixty years later, Guglielmo Marconi received the first trans-Atlantic radio signal on December 12, 1901, in St. John's, Newfoundland (now in Canada) using a kite-supported antenna for reception. The transmitting station in Poldhu, Cornwall, used a spark-gap transmitter to produce a signal with a frequency ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Northern Australia
The unofficial geographic term Northern Australia includes those parts of Queensland and Western Australia north of latitude 26° and all of the Northern Territory. Those local government areas of Western Australia and Queensland that lie partially in the north are included. Although it comprises 45% of the total area of Australia, Northern Australia has only 5% of the Australian population (1.3 million in 2019). However, it includes several sources of Australian exports, being coal from the Great Dividing Range in Queensland/New South Wales and the natural gas and iron ore of the Pilbara region in WA. It also includes major natural tourist attractions, such as Uluru (Ayers Rock), the Great Barrier Reef and the Kakadu National Park. Geography and climate Almost all of Northern Australia is a huge ancient craton that has not experienced geological upheaval since the end of the Precambrian. The only exception to this generalisation is the Wet Tropics of northern Queensla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Battle Of Shah-i-Kot
Operation Anaconda was a military operation that took place in early March 2002 as part of the War in Afghanistan. CIA paramilitary officers, working with their allies, attempted to destroy al-Qaeda and Taliban forces. The operation took place in the Shahi-Kot Valley and Arma Mountains southeast of Zormat.Naylor, Sean. "Not a Good Day to Die" Penguin Group (New York), 2014: This operation was the first large-scale battle in the post-2001 War in Afghanistan since the Battle of Tora Bora in December 2001. This was the first operation in the Afghanistan theater to involve a large number of U.S. forces participating in direct combat activities. Between March 2 and March 16, 2002 1,700 airlifted U.S. troops and 1,000 pro-government Afghan militia battled between 300 and 1,000 al-Qaeda and Taliban fighters to obtain control of the valley. The Taliban and al-Qaeda forces fired mortars and heavy machine guns from entrenched positions in the caves and ridges of the mountaino ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
