* Gravity: This pulls the satellite towards Earth, trying to bring it down.
* Orbital velocity: This is the speed at which the satellite travels sideways. This speed is just right to ensure that the satellite constantly falls towards Earth but never actually hits it.
Here's a simplified explanation:
Imagine throwing a ball horizontally. The ball travels a certain distance before falling to the ground. If you throw it faster, it will travel farther before falling.
A satellite is like a ball thrown with an incredibly high speed. Its sideways speed is so great that, as it falls towards Earth due to gravity, the Earth curves away beneath it. This continuous "falling" results in a circular or elliptical orbit around the Earth.
Why Satellites Crash:
Satellites can crash for several reasons:
* Insufficient orbital velocity: If a satellite slows down for any reason (like atmospheric drag or a malfunction), it loses the necessary sideways speed to maintain its orbit. This causes it to fall closer to Earth, eventually crashing.
* Collision: Satellites can collide with space debris or other satellites, causing damage and potential loss of orbit.
* Atmospheric drag: While the atmosphere is thin at high altitudes, it still exerts a small amount of friction on satellites, slowing them down over time. This drag can eventually pull a satellite out of orbit.
* Deliberate re-entry: Some satellites are deliberately sent back into the atmosphere to burn up and deorbit. This is often done at the end of their mission or when they become unusable.
In summary, satellites don't crash because of gravity alone. They crash because of factors that disrupt the delicate balance between gravity and their orbital velocity, causing them to fall out of orbit.
