Atmospheric drag

Atmospheric drag is like when you're running really fast and you feel the wind pushing against your face. When things travel through the air, like airplanes or satellites, the air can slow them down because it causes a kind of friction called drag.

Think about trying to run through water. It's much harder than running on land because the water slows you down. That's like atmospheric drag, but with air instead of water.

When satellites orbit the Earth, they are moving really fast. But even though space is mostly empty, there is still a little bit of air up there. The air molecules are so spread out that you can't feel them, but they're there. And as the satellite moves through the air, the air molecules push against it and slow it down just a little bit. This is what we call atmospheric drag.

Atmospheric drag is important because it affects how long satellites can stay in orbit. If the drag is too strong, the satellite will slow down and eventually fall back to Earth. That's why engineers have to design satellites to be able to withstand a certain amount of atmospheric drag.

So, just like you have to push against the wind when you're running outside, satellites and other things flying through the air have to push against atmospheric drag to stay where they are.