UNIVERSE
SATELLITESICY BODIES
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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1 hour
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12 hours
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24 hours
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365 days
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Detailed explanation-1: -Satellites in geostationary orbit (GEO) circle Earth above the equator from west to east following Earth’s rotation – taking 23 hours 56 minutes and 4 seconds – by travelling at exactly the same rate as Earth. This makes satellites in GEO appear to be ‘stationary’ over a fixed position.
Detailed explanation-2: -Certain orbital altitudes have special properties, like a geosynchronous orbit, in which a satellite travels around the Earth exactly once each day. The length of each red arrow in this diagram represents the distance traveled by a satellite in an hour. View animation. (NASA illustration by Robert Simmon.)
Detailed explanation-3: -This special, high Earth orbit is called geosynchronous. A satellite in a circular geosynchronous orbit directly over the equator (eccentricity and inclination at zero) will have a geostationary orbit that does not move at all relative to the ground. It is always directly over the same place on the Earth’s surface.
Detailed explanation-4: -The majority of satellites orbiting the Earth do so at altitudes between 160 and 2, 000 kilometers. This orbital regime is called low Earth orbit, or LEO, due to the satellites’ relative closeness to the Earth. Satellites in LEO typically take between 90 minutes and 2 hours to complete one full orbit around the Earth.
Detailed explanation-5: -In our animation, it goes around twice in one day. In reality, the satellite may orbit Earth once every hour-and-a-half or so, going around many times per day. An example of satellites in polar orbit are the three POES* satellites.
Detailed explanation-6: -A geostationary satellite travels from west to east over the equator. It moves in the same direction and at the same rate Earth is spinning.
Detailed explanation-7: -A satellite maintains its orbit by balancing two factors: its velocity (the speed it takes to travel in a straight line) and the gravitational pull that Earth has on it. A satellite orbiting closer to the Earth requires more velocity to resist the stronger gravitational pull.