MCQ Detailed View

Communication satellites are placed in specific orbits around the Earth to ensure continuous and reliable transmission of signals. The ideal orbit for most communication satellites is the geostationary orbit. A geostationary orbit is a circular orbit directly above the Earth’s equator at an altitude of approximately 35,786 kilometers (22,236 miles). Satellites in this orbit have an orbital period equal to the Earth’s rotation period, which is about 24 hours.

Because the satellite rotates at the same speed as the Earth, it appears stationary relative to a fixed point on the Earth’s surface. This property allows antennas on the ground to remain pointed at the same satellite without the need to track its movement continuously. Geostationary satellites are widely used for television broadcasting, weather monitoring, GPS, and telecommunications.

Other orbits, such as geosynchronous, also have a period of 24 hours, but they may have an inclined plane relative to the equator. This causes the satellite to appear to oscillate north and south over the Earth’s surface, making it less ideal for fixed communication antennas. Semi-synchronous orbits are typically used for navigation satellites, like those in the GPS system, with a period of about 12 hours.

Ground-based antennas rely on geostationary satellites for uninterrupted communication because these satellites provide constant coverage over specific regions. They form the backbone of global communication networks, enabling phone calls, television broadcasts, and internet services across continents.

In summary, communication satellites are placed in a geostationary orbit because it ensures constant positioning relative to Earth, allowing stable and continuous signal transmission for communication purposes. This is a key concept in space physics, satellite technology, and modern telecommunications.