There are almost 4900 satellites orbiting the earth. You should may have think of it that work ? Why are these satellites in totally different orbits ? How does the satellite do all of it's functions ? And what component are there inside them ? Let's explore and learn about satellites.
You already know that satellite stays in orbit, because of the balance between gravitational pull and centrifugal force. The angular velocity of the satellite is marked by the force balance equation that balances the gravitational and centrifugal forces. When the satellite is deployed it is given sufficient speed to balances these two forces.
A satellite near to earth requires more speed to resist the gravitational pull them the ones located further from the earth. Due to negligible resistance in space, satellites never lose speed. This means satellites will keep up their circular motion around our planet without any external energy source. Satellites are placed either in low earth orbit, medium earth orbit or geosynchronous orbit.
There is an fascinating region in space called the Van Allen belt. A region full of highly energetic charged particles, which could severly damage the electronics section of a satellite. Generally, it is preffered not to park satellites in the Van Allen belt.
The decision on what orbit is to be chosen for placing the satellite rely on the application and design of the satellite. If the satellite is built for earth observation, weather forecasts, geographic area surveying, satellite phone calls, etc. Then orbits closer to the earth chosen. LEO is the closest to the earth at an altitude of between 160 and 200 km and its orbital period is approximately 1.5 hours.
But these types of satellite cover less area of the earth so many satellites are essential to ac global coverage. That is why in the occasions of broadcasting a high orbit such as GEO is chosen. Satellittes in geosynchronous orbit are at a height of 35,786 km and rotate at the same angular speed as the earth.
It means that the satellite takes exactly 23 hours 56 minutes and four seconds to complete one rotation of the planet. Within the geosynchronous orbit, there is a special category of orbit called geostationery orbit, which is concentric the equator of the earth. These satellites remain stationery with respect to the earth.
About Me
Umang is a student of geography pursuing bachelor's in geography who enjoys indulging his passion including reading geography books and writing geography articles. My goal is to make every post valuable and something I'd want to read. Its mostly a Educational blog, meant to inspire. You can find my videos on youtube (there's a link in the upper right to jump to them) but posts are almost about geography .Other than writing blog on geography i also do illustration on Instagram. Enjoy Umang
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Good info
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