Satellites. "Man must rise above the Earth -- to the top of the atmosphere and beyond -- for only thus will he fully understand the world in which he lives. " Socrates made this observation centuries before humans successfully placed an object in Earth's orbit. And yet the Greek philosopher seemed to grasp how valuable a view from space might be, even if he didn't know how to achieve it. Those notions -- about how to get an object "to the top of the atmosphere and beyond" -- would have to wait until Isaac Newton, who published his now-famous cannonball thought experiment in 1729. His thinking went like this: Imagine you place a cannon atop a mountain and fire it horizontally. The cannonball will travel parallel to Earth's surface for a little while but will eventually succumb to gravity and fall to the ground.
Now imagine you keep adding gunpowder to the cannon. In October 1957, the Soviets finally proved Newton correct when they launched Sputnik 1 -- the first artificial satellite to orbit Earth. Learn Latitude and Longitude. A key geographical question throughout the human experience has been, "Where am I? " In classical Greece and China, attempts were made to create logical grid systems of the world to answer this question. The ancient Greek geographer Ptolemy created a grid system and listed the coordinates for places throughout the known world in his book Geography.
But it wasn't until the middle ages that the latitude and longitude system was developed and implemented. This system is written in degrees, using the symbol °. Latitude When looking at a map, latitude lines run horizontally. Longitude The vertical longitude lines are also known as meridians. How Latitude and Longitude Work Together To precisely locate points on the earth's surface, degrees longitude and latitude have been divided into minutes (') and seconds (").
To locate the latitude and longitude of a specific place on earth, see my Locate Places Worldwide collection of resources. Lat Long Map of Australia. The Commonwealth of Australia is located on the geographic coordinates of 25.0000° S latitude and 135.0000° E longitude in Australia. Australia, the smallest among the continents of the world, is located in between 27°00' South Latitude and 133°00' East Longitude. Some of Australia 's major cities are located in slightly different latitude and longitudinal areas.
Melbourne in Australia is situated in between 37°49' South Latitude and 144° 58' East Longitude. Similarly, Adelaide's latitude and longitude are 34° 56'. Australia 's latitude and longitude has given it a particular type of climate. In the south and eastern part of Australia the weather is generally temperate where summer and winter climate is not marked by extremities and is enjoyable. But in the northern part of Australia the climate is very hot and humid during summer and cold in winter. What is Migration? In ecology and animal behaviour, Migration, Migratory behavior, or Migratory may refer to: Other scientific uses[edit] Information technology[edit] Data migration, the process of transferring data between storage types, formats, or computer systemsSystem migration, the tasks involved when moving data and applications from current hardware to new hardwareSoftware migration, refers to the conversion, rewriting or porting of a legacy system to a modern computer systems Arts and entertainment[edit] Other uses[edit] Piercing migration, in body modification, a process that occurs when a body piercing moves from its initial location See also[edit]
Latitude and Longitude. Geographic coordinate system. A graticule on a sphere or an ellipsoid. The lines from pole to pole are lines of constant longitude, or meridians. The circles parallel to the equator are lines of constant latitude, or parallels. The graticule determines the latitude and longitude of position on the surface. Latitude and Longitude of the Earth A geographic coordinate system is a coordinate system that enables every location on the Earth to be specified by a set of numbers or letters. The coordinates are often chosen such that one of the numbers represents vertical position, and two or three of the numbers represent horizontal position.
A common choice of coordinates is latitude, longitude and elevation.[1] Geographic latitude and longitude[edit] A line, which was intended to pass, through the Royal Observatory, Greenwich (a suburb of London, UK) was chosen as the international zero-longitude reference line, the Prime Meridian. UTM and UPS systems[edit] Stereographic coordinate system[edit] Geodetic height[edit] is. Identifying sharks. Species implicated in attacks The word 'shark' is used to describe a broad range of aquatic creatures, but not all sharks are dangerous to humans.
Nearly all fatal attacks in coastal waters are attributed to just three species: bull sharks, tiger sharks and great white sharks (also know as white pointers). Bull shark Alternative names: river whaler, freshwater whaler, Swan River whaler. The bull shark, Carcharhinus leucas, is found along coastlines in tropical and subtropical oceans, and in Australia occurs from central NSW coast, across the northern coast to Perth, Western Australia. Bull shark distribution extends south to Sydney during the warmer summer months. It is the only widely distributed shark that penetrates far into fresh water for extended periods where it sometimes breeds. Bull shark Great white shark Alternative names: white pointer, white shark, white death. Great white shark Tiger shark References: Sharks and Rays of Australia (2nd ed.); Peter R. Tiger shark Bronze whaler Mako. Image. Latest Sharks. Hawaii tiger shark migration in fall coincides with rise in bites.
Traditional Hawaiian stories warn about an increased danger of shark bites in the fall, from September to November. A recent study shows that there could be something behind this folk wisdom: During this time, an increased number of tiger sharks make their way to the islands, likely to give birth. "Both the timing of this migration and tiger shark pupping season coincide with Hawaiian oral traditions suggesting that late summer and fall, when the wiliwili tree blooms, are a period of increased risk of shark bites," said study co-author Carl Meyer, a researcher at the University of Hawaii, in a statement. But Meyer and lead author Yannis Papastamatiou, a researcher at the Florida Museum of Natural History, said that people shouldn't jump to the conclusion that this migration is directly related to recent shark bites near the islands.
The study that found the potential link involved tagging tiger sharks over a seven-year period, and included more than 100 animals, most of them female. Great White Shark. Shark Finning. A fisherman holds a freshly cut dorsal fin from a scalloped hammerhead shark (Sphyrna lewini). Every year, humans kill an estimated 100 million sharks. Removing sharks in large numbers can have ripple effects that throw entire ecosystems out of balance. Credit: © Jeff Rotman/jeffrotman.com by Caty Fairclough Sharks have been feared hunters ever since people first observed them swimming in the vast ocean.
Shark fins are tempting targets for fishermen because they have high monetary and cultural value. Many fishermen prefer to practice shark finning instead of bringing whole sharks to the market because the fins are far more valuable than the rest of the body, sometimes selling for as much as $500 a pound ($1,100 a kilogram). However, the animal cruelty implications are not the only reason to stop this practice. MaryEllen and Paul, Flickr Such dramatic population plunges are not only dangerous for sharks but also for entire ecosystems.
Progress Tags: Shark finning, Sharks, Endangered species. How do sharks migrate? How Do Sharks Migrate? There are many unanswered questions as to how sharks and other animals know when and in what direction to migrate. How do animals know that there is more abundant food and water, more comfortable temperatures or more favorable breeding grounds located hundreds or even thousands of miles away? Even more amazing, how do animals navigate over great distances when there are no permanent landmarks or maps to guide them? Researchers have proven that migratory animals such as birds or caribou use a wide variety of senses to navigate from one point to another. The most obvious are physical and visual cues, such as following river beds, coastlines or mountain ranges from the ground or the air. Birds, some fish, and turtles also navigate by following the sun, by light waves reflecting off water, by responding to the earth's magnetic fields and even by the stars at night.
Sharks navigate mainly by electro-reception and a sensitivity to pressure and water temperature. Global Positioning System. Artist's conception of GPS Block II-F satellite in Earth orbit. The Global Positioning System (GPS) is a space-based satellite navigation system that provides location and time information in all weather conditions, anywhere on or near the Earth where there is an unobstructed line of sight to four or more GPS satellites.[1] The system provides critical capabilities to military, civil and commercial users around the world. It is maintained by the United States government and is freely accessible to anyone with a GPS receiver. The GPS project was developed in 1973 to overcome the limitations of previous navigation systems,[2] integrating ideas from several predecessors, including a number of classified engineering design studies from the 1960s.
GPS was created and realized by the U.S. Department of Defense (DoD) and was originally run with 24 satellites. It became fully operational in 1995. Bradford Parkinson, Roger L. History[edit] Predecessors[edit] Official logo for NAVSTAR GPS. Satellite Learning Center. How Do Satellites Work? A satellite works by receiving radio signals sent from the Earth and resending the radio signals back down to the Earth. In a simple system, a signal is reflected, or "bounced," off the satellite. For example, it is possible to bounce a signal off the surface of the Moon back down to Earth. Because the Moon is very far away, for this to work the signal from the Earth must be very strong and the receiver receiving the signal must be sensitive enough to detect the very weak signal receive back from the moon.
Unlike a passive satellite such as the moon or the early ECHO satellite, a modern communications satellite receives the radio signal and sends it back down to Earth stronger than it was received. People communicate to a satellite using an antenna on the ground, which called an "earth station" in technical terms. The satellite receives these signals, makes them stronger, and then re-transmits them back down to the Earth. How Do Satellites Work. How GPS Works - GPS Technology Explained. The Global Positioning System (GPS) is a technical marvel made possible by a group of satellites in earth orbit that transmit precise signals, allowing GPS receivers to calculate and display accurate location, speed, and time information to the user. By capturing the signals from three or more satellites (among a constellation of 31 satellites available), GPS receivers are able to use the mathematical principle of trilateration to pinpoint your location.
With the addition of computing power, and data stored in memory such as road maps, points of interest, topographic information, and much more, GPS receivers are able to convert location, speed, and time information into a useful display format. GPS was originally created by the United States Department of Defense (DOD) as a military application. The system has been active since the early 1980s, but began to become useful to civilians in the late 1990s.