Difference between revisions of "Environmental factors"
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<b>Disposal of GPS satellites</b> | <b>Disposal of GPS satellites</b><br> | ||
Satellites can be disposed of in two ways. They can move up to a disposal orbit(~300 km further) or they can fall from space to Earth. | Satellites can be disposed of in two ways. They can move up to a disposal orbit(~300 km further) or they can fall from space to Earth. | ||
<br> | <br> | ||
''Falling from orbit''<br> | ''Falling from orbit''<br> | ||
When a satellite falls from orbit, 10 to 40 percent of its mass survives reentry and falls at random locations on Earth. To date noone has been killed or injured by this. The debris is also not cleaned up. | When a satellite falls from orbit, 10 to 40 percent of its mass survives reentry and falls at random locations on Earth. To date noone has been killed or injured by this. The debris is also not cleaned up. | ||
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''Moving to a disposal orbit''<br> | |||
Studies show that satellites placed in disposal orbits can in 20-40 years encroach into the operating constellation. These can then collide with operating satellites or can explode and shower the operating satellites with debris. | |||
===References=== | ===References=== | ||
1. [http://www.slate.com/id/2117519/ Where satellites go when they die]<br> | 1. [http://www.slate.com/id/2117519/ Where satellites go when they die]<br> | ||
2. [http://www.aero.org/news/newsitems/procedures-030702.html Disposal procedures]<br> | 2. [http://www.aero.org/news/newsitems/procedures-030702.html Disposal procedures]<br> | ||
3.[http://www.soi.city.ac.uk/~dk708/pg3_3.htm Effect on environment]<br> | 3. [http://www.soi.city.ac.uk/~dk708/pg3_3.htm Effect on environment]<br> | ||
Revision as of 18:55, 19 March 2006
Research questions Environmental factors
Egon:
1. Will LBS have positive impact on the environment, due to less searching time and better location based information. (less use of energy / fuel??)
Reza:
1. How far is the air in major business areas over crowded with the same frequency?
Amarantha:
1. Do satellites affect/change the earth's atmosphere in any way?
2. How are satellites disposed of at the end of their useful life? How long is that life?
Werner:
1. To what extend can the phenomenon of electrical pollution limit the expansion of the use and application of LBS ? ([1])
Research Answers Environmental Factors
GPS satellites and the environment
GPS satellites in themselves do not directly affect the environment in a negative or positive manner. However, they do deplete the earth's natural resources on launch. They use up massive amounts of fuel at that time. Once in space, they are however powered by solar energy for sending the signals. They must still have fuel on board for movement for their remaining useful life. A GPS Satellite has a lifetime of 5 - 10 years. There are currently 60 working GPS satellites in orbit. Replacements are continously being built and sent into orbit.
Disposal of GPS satellites
Satellites can be disposed of in two ways. They can move up to a disposal orbit(~300 km further) or they can fall from space to Earth.
Falling from orbit
When a satellite falls from orbit, 10 to 40 percent of its mass survives reentry and falls at random locations on Earth. To date noone has been killed or injured by this. The debris is also not cleaned up.
Moving to a disposal orbit
Studies show that satellites placed in disposal orbits can in 20-40 years encroach into the operating constellation. These can then collide with operating satellites or can explode and shower the operating satellites with debris.
References
1. Where satellites go when they die
2. Disposal procedures
3. Effect on environment