The History and Future of Satellite Communications

Guest Post by Philip J Reed on behalf of WildBlue

Satellites help form the foundation of the global telecommunications network comprising telephone, television, and Internet services. They allow anyone in any location to pick up a cell phone and dial somebody across the world or to watch a sports game in another country. Satellites were once believed to be science fiction and outside humanity’s technological prowess, but the past half century has marked dramatic technological advances once thought impossible.

The Start of a Dream

As early as 1945, Arthur C. Clarke wrote about a network of satellites capable of transmitting television signals around the world. However, the idea failed to catch on at first, and Clarke’s articles and stories were considered fanciful until the Soviet Union launched the satellite Sputnik in 1957.

During the height of the Cold War, the Soviet Union showed that orbital satellites were not only theoretically possible but feasible with the current technology of the day. Overnight, news outlets and government agencies around the world began to seriously consider what capabilities they could arm satellites with.

Many initial theories centered around Clarke’s idea of a global communications network, but there were also fears that governments could arm satellites with ballistic missiles or other weapons. While Clarke’s peaceful vision has held true so far, there does not yet exist a comprehensive space weapons ban. However, U.S. President Barack Obama signaled a wish to ban anti-satellite weapons in 2009.

The First Communications Satellites

In 1960, AT&T filed for permission to place a communications satellite in orbit. Two years later, the first active communications website, Telstar-1, began to receive and transmit signals to ground-based dishes.

These satellites were placed into geostationary orbit over the equator. Because they completed one orbit every 24 hours, they were always located directly above the same point on the ground, allowing ground-based satellite dishes to maintain a static angle. Unfortunately, signals from equatorial satellites grow weak at high latitudes, which can prove problematic for regions like northern Canada or southern Chile.

The first communications satellites were capable of only a few dozen simultaneous phone calls. Computer circuits were both primitive and expensive, and the rockets capable of carrying the satellites into orbit cost thousands of dollars per pound for each payload. Given these costs, it’s nothing short of remarkable that AT&T, Comsat, and other early satellite providers were able to quickly and completely recoup their losses, paving the way for an entirely new industry.

Ubiquitous Service

Once telecommunications providers started developing new satellites, the industry made advances on a monthly basis. Today, integrated circuits used in satellites cost a small fraction of the price, but they’re capable of transmitting thousands of simultaneous telephone calls instead of dozens.

Just three years after the launch of Telstar-1, AT&T proposed a satellite TV network for the continental United States, but the proposal was promptly ignored as in the case of Arthur C. Clarke’s 1945 article. It would not be until 1972 that a major telecommunications company, Telesat Canada, would begin providing satellite television service. Western Union launched the first TV satellite for the United States in 1974.

Less than one year later, HBO introduced premium television service to U.S. customers, and high adoption rates spurred further satellite TV development. However, satellite telephone service did not take off until the 1990s, and satellite Internet became popular only after the turn of the century.

Where Does the Future Lead?

Over the past decade, launch services have moved from the public to private sectors. SpaceX, or Space Exploration Technologies Corporation, has built and tested two different rocket designs. The SpaceX Dragon 9 rocket was so innovative that it slashed launch costs by 90 percent, driving launch costs down below $1,000 per pound.

Satellites themselves are also smaller, cheaper, and more powerful than ever before. Cube satellites can measure as little as 1,000 cubic centimeters, about the size of a grapefruit. While cube satellites are used primarily for scientific research, they demonstrate how compressed satellite technology has become.

Because satellites are cheaper to build and launch into orbit than ever before, they will continue to complement land-based telecommunications for the next few decades. Whether or not satellite communications can sustain growth with limited frequencies and bandwidth remains to be seen.

For further reading…
http://history.nasa.gov/satcomhistory.html
http://www.nss.org/articles/falconheavy.html
http://www.reuters.com/article/2009/01/25/us-usa-obama-space-idUSTRE50O15X20090125

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Vertical Farming:Agriculture of Future

The Problem

By the year 2050, nearly 80% of the earth’s population will reside in urban centers. Applying the most conservative estimates to current demographic trends, the human population will increase by about 3 billion people during the interim. An estimated 109 hectares of new land (about 20% more land than is represented by the country of Brazil) will be needed to grow enough food to feed them, if traditional farming practices continue as they are practiced today. At present, throughout the world, over 80% of the land that is suitable for raising crops is in use (sources: FAO and NASA). Historically, some 15% of that has been laid waste by poor management practices. What can be done to avoid this impending disaster?

A Potential Solution: Farm Vertically

Vertical farming is a concept that argues that it is economically and environmentally viable to cultivate plant or animal life within skyscrapers, or on vertically inclined surfaces. The idea of a vertical farm has existed at least since the early 1950s and built precedents are well documented by John Hix in his canonical text “The Glass House”.

Irrespective of their origins, there are three classifications debated by contemporary scholars.

  • The phrase “vertical farming” was coined by Gilbert Ellis Bailey in 1915. In his book “Vertical Farming”, Bailey defined the earliest meanings and methods of vertical farming:   “Vertical Farming”, to coin a name, is the keynote of a new agriculture that has come to stay, for inexpensive explosives enable the farmer to farm deeper, to go down to increase area, and to secure larger crops. Instead of spreading out over more land he concentrates on less land and becomes an intensive rather than an extensive agriculturist, and soon learns that it is more profitable to double the depth of his fertile land than to double the area of his holdings, and he learns that his best aid and servant in this work is a good explosive. Peace congresses demand that swords be turned into pruning hooks. The farmer is busy turning explosives from war to agriculture, from death dealing to life giving work.
  • The second category of vertical farming falls under the concepts proposed and built by architect Ken Yeang developed at least ten years before Despommier. Yeang proposes that instead of hermetically sealed mass produced agriculture that plant life should be cultivated within open air, mixed-use skyscrapers for climate control and consumption (i.e. a personal or communal planting space as per the needs of the individual). This version of vertical farming is based upon personal or community use rather than the wholesale production and distribution plant and animal life that aspires to feed an entire city. It thus requires less of an initial investment than Despommier’s “The Vertical Farm”. However, neither Despommier nor Yeang are the conceptual “originators”, nor is Yeang the inventor of vertical farming in skyscrapers.
  • The third category vertical farming was made by American ecologist Dr. Dickson Despommier. Despommier argues that vertical farming is legitimate due to environmental reasons. He claims that the cultivation of plant and animal life within skyscrapers will produce less embedded energy and toxicity than plant and animal life produced on natural landscapes. He moreover claims that natural landscapes are too toxic for natural, agricultural production, despite the ecological and environmental costs of extracting materials to build skyscrapers for the simple purpose of agricultural production.

Advantages

  • Preparation for the future
  • Protection from weather-related problems
  • Organic crops
  • Halting mass extinction
  • Positive Impact on human health
  • Urban growth
  • Energy production

Here is a Video on this concept

Technologies and devices

Vertical farming relies on the use of various physical methods to become effective. Combining these technologies and devices in an integrated whole is necessary to make Vertical Farming a reality. Various methods are proposed and under research. The most common technologies suggested are:
Greenhouse
The Folkewall and other vertical growing architectures
Aeroponics / Hydroponics / Aquaponics
Composting as a Waste to Energy Method
Grow light
Phytoremediation
Skyscraper

Links and Sources:

Wikipedia

BBC

vertical farm site

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sharonstjoan's avatarEchoes in the Mist

 

Quang Thien bounds across the grass of Animals Asia’s sanctuary in Vietnam.

Authorities were able to confiscate her from a bile bear farm because she had not been microchipped, which is required by law.  Her front left paw is missing, so it’s likely that she was illegally trapped in the wild and then sold.  Her life at the sanctuary is a far cry from her existence in the tiny cage where she was kept imprisoned at the bile bear farm.  She loves being free to run and play with her bear friends. But the Sanctuary and her newly found happy life are now in danger.

 

104 bears rescued from bile bear farms and the wildlife trade, who were given sanctuary seven years ago, in 2005, at the Tam Dao national park in northern Vietnam, at a beautiful center run by Animals Asia, are now under threat of eviction…

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