Question

How much time is required by GPS satellites to make one complete revolution around the Earth?

• A. \(12\text{ hours (Standard Time)} \)
• B. \(12\text{ hours (Solar Mean Time)} \)
• C. \(12 \text{ hours (Solar Apparent Time)} \)
• D. \(12 \text{ hours (Sidereal Time)} \)

Hint:

Sidereal time is used in celestial navigation and satellite tracking as it accounts for the Earth's rotation relative to distant stars instead of the Sun.

Answer 1

The Correct Option is D

Step 1: Understanding GPS satellite orbits. GPS satellites orbit the Earth at an altitude of approximately 20,200 km in a Medium Earth Orbit (MEO).
Step 2: Defining the time for one revolution. - GPS satellites complete one full revolution every 11 hours, 58 minutes in sidereal time, which is approximately 12 hours in sidereal time. - Sidereal time refers to the Earth's rotation relative to the fixed stars, rather than the Sun.
Step 3: Selecting the correct option. Since GPS satellites operate based on sidereal time rather than standard or solar time, the correct answer is 12 hours (Sidereal Time).