Batteries are used to power all satellite subsystems
During eclipse periods
Satellite Batteries: Powering Subsystems During Eclipse
Batteries are an indispensable part of a satellite's power system, ensuring that all satellite subsystems receive continuous electrical energy, even when the primary power source is unavailable. Satellites primarily rely on solar arrays to generate electricity when they are exposed to sunlight.
Batteries Role in Satellite Power Systems
A typical satellite power system is designed for reliability and redundancy. It consists of two main components for power supply:
- Solar Arrays: These panels convert sunlight directly into electrical energy, which powers the satellite's subsystems and also charges the onboard batteries when the satellite is in direct sunlight.
- Batteries: These are crucial for storing excess energy generated by the solar arrays. Their primary function is to provide power to the satellite's subsystems during specific operational phases when the solar arrays cannot produce electricity.
The most significant of these phases are the eclipse periods. An eclipse period occurs when the Earth (or another celestial body) blocks the sunlight from reaching the satellite's solar arrays. During such times, the solar arrays become inactive, and the batteries take over as the sole power source, discharging to maintain the functionality of all critical satellite subsystems.
Analyzing Satellite Battery Usage Options
Let's evaluate the given options to understand precisely when batteries are used to power satellite subsystems:
| Option | Analysis |
|---|---|
| At all times | This is incorrect. While batteries are always present, solar arrays are the primary power source for satellite subsystems during periods of direct sunlight. Batteries are typically charged or maintained during these times. |
| Only during emergencies | This is also incorrect. Although batteries can provide emergency power, their routine and critical function is to supply power during predictable and regularly occurring eclipse periods, which are not considered emergencies. |
| During eclipse periods | This is the correct function. When a satellite enters Earth's shadow (an eclipse period), the solar arrays cannot generate power. At these times, the stored energy in the batteries is discharged to ensure continuous power to all satellite subsystems. |
| to give the solar arrays a rest | This statement is inaccurate. Solar arrays are designed for continuous operation and do not require "rest." They generate power whenever exposed to sunlight. |
In summary, the fundamental role of batteries in a satellite's power system is to provide uninterrupted electricity to all its subsystems specifically during eclipse periods, ensuring the mission's continuity.
Important Questions from Satellite Communications
- In satellite communication, the downlink frequency is always_____ the uplink frequency.
ISRO launched ______, it’s 42nd communication satellite, in December 2020.
Consider the following bands/waves :
1. L band
2. C band
3. $K_u$ band
4. $K_a$ band
Arrange them in increasing frequency order, the correct sequence of the ascending order in terms of frequency is
Consider the following statements:
a. The speed of telecommunication satellite relative to earth is zero.
b. Hence it appears to be stationary to a person on the earth.
List of few satellites manufactured by ISRO is given below along with the date of their launch. Which two of the following Satellites failed to reach the orbit ?
Satellite
Launch Date
A. GSAT-2
8 th May, 2003
B. GSAT-4
15 th April, 2010
C. GSAT-5P
25 th December, 2010
D. GSAT-12
15 th July, 2011
