SPACE ENVIRONMENT: GRAVITY


Contrary to what some people think, there is gravity in space only that it gets weaker with distance. Gravity is responsible for keeping the moon and other satellites orbit the Earth. However, it is also gravity that causes satellites, especially those near the Earth's surface to 'fall back' to Earth. 

Slowly, as the satellite moves in space, it constantly gets pulled back to Earth. This event is aggravated by atmospheric drag, which is discussed in the next article. The closer a satellite is to the Earth's surface, expect that it will have a shorter lifetime. With this knowledge, you normally would want to bring your satellite to a higher altitude if you want it to stay in space for a longer time. Gravity can also help determine the amount of propellant that the spacecraft needs to move between orbits. 

Space Environment

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