How NASA calcuating/determining orbit of crafts/satellites?

[TYRT]

We can check out by 'M' orbit view but How NASA calcuating orbits? Do you know something about this?

[Ralathon]

A stopwatch and a telescope basically.

If you know the position of the object at several points in time, and you do a whole boatload of maths to take into account perspective and the earth's rotation you can figure out the orbit of an object.

You can also get some additional information to help you along for man made objects, such as doppler shift in the radio signal so you can figure out its velocity and accelerometers on board the ship that tell you how fast it is accelerating. By pinging the ship you can also figure out the distance. All of these allow you to calculate the orbit very accurately.

[TYRT]

A stopwatch and a telescope basically.

If you know the position of the object at several points in time, and you do a whole boatload of maths to take into account perspective and the earth's rotation you can figure out the orbit of an object.

You can also get some additional information to help you along for man made objects, such as doppler shift in the radio signal so you can figure out its velocity and accelerometers on board the ship that tell you how fast it is accelerating. By pinging the ship you can also figure out the distance. All of these allow you to calculate the orbit very accurately.

Looks logical, thanks

[K^2]

It is done via numerical integration methods. There are errors, but given a "high" order implicit Runge Kutta method and a small enough time step they can compute trajectories with satisfactory precision.

Implicit methods significantly reduce errors in kinetic energy, but there is no general conservative integration method for a many body gravity problem. You can get "close enough", however, by just throwing enough computer power at it.

("High" for implicit methods is something like 3.)