Eli5:How do things get to Earth’s orbit?

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I have some basic knowledge in physics (at least I think so) and know why objects on the orbit don’t fall down to Earth.My question is how the objects (meteor debris etc) got there.Aren’t they supposed to have the exact speed and trajectory? Did all of them manage to fit in these conditions?
Sorry for possible mistakes, English isn’t my first language

In: Physics

If you throw a ball as hard as you can in a straight line forward, you’ll see that after a certain distance, it will have succumbed to gravity and fall to the ground.

If you shoot a handgun in a straight line forward, the bullet will travel further before falling to the Earth. Use a high power rifle, and it’ll be even further.

As an object starts moving fast enough, what you find is that the earth will start “falling away” just as fast as the object falls to the Earth. This is the basis for an orbit.

Every satellite we have in orbit is still majorly affected by gravity. However, they’re moving so fast to the side that they never hit the Earth.

Basically objects in orbit around the Earth are falling to Earth, but their horizontal velocity means that they keep missing the Earth https://youtu.be/Zu-Sp3I0c1Q

Most debris does fall down to Earth however that debris that has the correct velocity stay in orbit for a while until minor collisions slow them down and eventually they fall to Earth. Basically the bits in orbit have what is known as survivorship bias https://youtu.be/geOdDSs0tjY

While a singular orbit needs a exact speed/trajectories, if you change them, they will still be in orbit, just a slightly changed one.

When it comes to meteors, they are not in orbit around the earth (as they would not hit earth then), usually they come from outside the earth gravities influence and happen to have a crash course with earth.

The stuff thats actually in earths orbit is mostly sattelites and the trash that was produced when placing them there. There are no significant asteroids/meteors that directly orbit earth closely, apart from the moon.

There are a couple asteroids who have a loose gravitational bound with earth which you could call a large orbit, these are likely just leftovers when the solar system was still a large disk of asteroids.

Lastly one way how asteroids could get into orbit is if two asteroid near earth collide and create a asteroid with just the right velocity to orbit earth.

First, do not confuse natural objects orbiting with man-made objects out there intentionally.

A satellite or space craft does need to be maintaining a specific speed to continue to orbit. Accelerating, it will attain a higher orbit, and actually slow relative to the ground, if they lose orbit, they can destabilize and fall to earth.

Natural objects in stable orbit are actually rare, if there even are any in earth orbit (other than the moon). Since they do not have a specific orbit, they are unstable and lose orbit. The meteors you see, did not “lose” orbit, they just never were in Earth orbit, just happened to get too close to Earth.

Objects like our moon were the result of an impact. There was a large collision way long ago and resulted in debris getting shot from the earth. Over enough time the moon formed from the remnants in a stable orbit since it didn’t have the right trajectory to collide together again or the energy to escape.

Planets can also catch moons. When a body passes by very close and loses energy in the upper atmosphere it can get captured into orbit. Mars has two asteroid like moons that were most certainly captured this way.