*Question T8B10:
What is a LEO satellite?*  

*Correct Answer is  D: A satellite in low earth orbit*  

### AI Response: (may contain errors)  

A LEO (Low Earth Orbit) satellite is defined as a satellite that orbits the Earth at a relatively low altitude, typically between 160 km (about 100 miles) and 2,000 km (about 1,200 miles) above the Earth's surface. 

### Correct Answer: 
**D: A satellite in low earth orbit**  
- LEO satellites are used for various applications, including communications, Earth observation, and scientific research. Their low altitude allows for lower latency in communication and higher resolution imaging.

### Why the Other Choices are Incorrect:
- **A: A sun synchronous satellite**  
  - This refers to a specific type of orbit where the satellite passes over the same point on the Earth's surface at the same local solar time. While some sun-synchronous satellites can be in LEO, not all LEO satellites are sun-synchronous.

- **B: A highly elliptical orbit satellite**  
  - Highly elliptical orbits have a significant variation in altitude, with parts of the orbit being much closer to Earth and others much farther away. LEO satellites do not fit this description as they maintain a relatively consistent low altitude.

- **C: A satellite in low energy operation mode**  
  - This term does not accurately describe the orbit of a satellite. Satellites can operate in various energy modes regardless of their orbital altitude. LEO satellites can operate in high or low energy modes depending on their mission requirements.

### Summary:
- LEO satellites are specifically defined by their low altitude orbit around the Earth, making option D the correct choice. Understanding the characteristics of different types of orbits is crucial for the Extra Class exam.