how can satellites and space ships stay orbiting around the Earth if our planet is moving at very high speeds across the universe?
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You’re absolutely correct that the Earth is moving at very high speeds, both in relation to the Sun and in relation to the galaxy.
But the thing is, *so are the satellites and space ships.* They launched from Earth, so they’re moving at the same speed.
If you have an ant on your arm walking around, and you are walking, on a bus, which is driving at 50 kilometers per hour, which is on the earth moving at over 1000 kilometers per hour… the ant is just going to stay on your arm. Because to the ant, your arm is stationary.
It’s the same thing, the motion is relative to the next higher thing it’s attached to. The moon travels around the earth which travels around the sun which travels around the galaxy. But to the moon, everything else is stationary.
Imagine you shoot an arrow from the back of a moving train towards the front. Even if the train is moving very fast, the arrow would travel some distance. If there is no gravity and no air resistance, it’ll keep on going.
Now the train is going 100mph and arrow is going 50mph with respect to train. Someone standing on the station platform would see the arrow going at 150mph. This is relative speed based on the frame of reference of the observer.
How can you stay in a plane when it flies 500mph? Just fine, have a nap if you wish. In relation to the plane, you are sitting perfectly stationary, what does it matter how fast the plane is in relation to the ground?
It’s important to understand there is no preferred frame of reference for the universe, speed is always relative between two objects, when you are orbiting a planet, then your speed in relation to the planet is all that matters. What is your speed in relation to other planets, stars or galaxies, is not relevant.
There’s essentially nothing in space to “slow” anything down besides gravity. And since gravity goes in all directions, the further you get from a source of gravity, the less it effects things, very quickly. So only “near” objects really have an effect on one another. So the gravity of the Earth keeps anything small close to it, and they travel with it. And the Earth is most effected by the gravity of the Sun, and travels with it. And the sun moves about whatever is at the center of the Milky Way. And so on. It’s all systems of smaller things moving about bigger things.
They are also moving at those same speeds. This is why it’s actually very hard to de orbit into the sun. If you launched from earth and pointed your spaceship directly at the sun you’d miss it. You would first need to aim practically opposite the direction of Earth’s orbit and firing your engines would actually be slowing you down.
Related to this is they are stuck in the planets gravity well. While logically your brain tells you that if you could move the Sun all the other planets would get left behind, what would happen is all the planets would come with the sun as it is moved.
Imagine you shoot an arrow from the back of a moving train towards the front. Even if the train is moving very fast, the arrow would travel some distance. If there is no gravity and no air resistance, it’ll keep on going.
Now the train is going 100mph and arrow is going 50mph with respect to train. Someone standing on the station platform would see the arrow going at 150mph. This is relative speed based on the frame of reference of the observer.
They are also moving at those same speeds. This is why it’s actually very hard to de orbit into the sun. If you launched from earth and pointed your spaceship directly at the sun you’d miss it. You would first need to aim practically opposite the direction of Earth’s orbit and firing your engines would actually be slowing you down.
Related to this is they are stuck in the planets gravity well. While logically your brain tells you that if you could move the Sun all the other planets would get left behind, what would happen is all the planets would come with the sun as it is moved.
Being in orbit means that satellites are at just the right speed to both overcome gravity and not crash into Earth AND not fly away.
Objects that are going too slow fall into earth, objects that are going too fast get flung away. The rest get trapped by Earth’s gravity and follow it wherever it goes.
If you get a piece of wire, tie an apple in one end and hold the other and start spinning and you’ll see the same behaviour. If you move at the right speed the apple will go with you, otherwise either the string will break off or it will fall into the ground.
Being in orbit means that satellites are at just the right speed to both overcome gravity and not crash into Earth AND not fly away.
Objects that are going too slow fall into earth, objects that are going too fast get flung away. The rest get trapped by Earth’s gravity and follow it wherever it goes.
If you get a piece of wire, tie an apple in one end and hold the other and start spinning and you’ll see the same behaviour. If you move at the right speed the apple will go with you, otherwise either the string will break off or it will fall into the ground.
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