Question

Distance of communication satellite from the surface of the Earth is:

• A. 36000 km
• B. 3600 km
• C. 36000 mile
• D. 36000 metre

Hint:

Geostationary orbit altitude<36,000 km from Earth’s surface.

Answer 1

The Correct Option is A

Geostationary communication satellites are placed in a specific type of orbit known as the geostationary orbit (GEO). This orbit is located approximately 36,000 kilometers (about 35,786 km to be precise) above the Earth's equatorial plane. The key characteristics and reasons for this orbital placement are:

Orbital Period Matching Earth's Rotation: At this altitude, the satellite completes one full orbit around the Earth in exactly 24 hours, which matches the Earth's rotation period about its axis. This synchronization means that the satellite remains fixed over a particular point on the Earth's surface.
Fixed Position Relative to Earth: Because the satellite appears stationary from any fixed position on Earth, ground antennas can be permanently aimed at the satellite without the need for tracking systems. This greatly simplifies the design and operation of communication systems.
Wide Coverage Area: From this high vantage point, a single geostationary satellite can cover roughly one-third of the Earth's surface. This allows for efficient communication coverage of large geographical areas, including entire continents and oceans.
Applications: Geostationary satellites are widely used for television broadcasting, weather monitoring, satellite radio, and telecommunications including telephone and internet services. Their fixed position ensures uninterrupted communication links.
Orbital Constraints: To maintain a geostationary orbit, the satellite must orbit in the Earth's equatorial plane (zero inclination) and at the precise altitude of approximately 35,786 km above mean sea level. Any deviation results in the satellite appearing to move relative to the Earth's surface, which can disrupt communication.
In summary, placing communication satellites at approximately 36,000 km altitude in a geostationary orbit allows for continuous, reliable communication with fixed ground stations, making them essential components of global communication networks.