Atmospheric drag on an artificial satellite orbiting the Earth

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To calculate the x, y, and z components of atmospheric drag on an artificial satellite, the relative velocity between the satellite and the rotating atmosphere must be determined. The atmosphere co-rotates with the Earth, and its motion can be calculated using the formula for rotational velocity, taking into account the satellite's altitude and latitude. The z component of the atmosphere's velocity is zero, while the x and y components can be derived using the cross product of the satellite's position vector and the Earth's angular velocity vector. This approach allows for the calculation of the atmospheric drag experienced by the satellite in low Earth orbit. Understanding these components is crucial for accurate drag calculations in orbital mechanics.
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Consider an artificial satellite orbiting the Earth and suppose that the atmosphere co-rotates with the Earth.

I need to calculate x, y and z components of the atmospheric drag.

I know how to calculate the drag in a non-spinning atmosphere and I have all the data to do that, but the Earth’s rotation confuses me.

I know the x, y and z components of the satellite state (position and velocity). The z-axis is the Earth’s rotation axis and the x-axis and y-axis lie on the equatorial plane. The exes do not rotate (it’s an inertial reference frame).

Please, could somebody help me?
 
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The altitude of the satellite is not stated. Atmospheric drag is only significant for objects in low Earth orbits. The shape, size, and orientation of the satellite are also not stated.
 
You can calculate the x/y/z motion of the atmosphere at the position of the satellite and subtract that from the satellite velocity to find the relative velocity.
 
mfb said:
You can calculate the x/y/z motion of the atmosphere at the position of the satellite and subtract that from the satellite velocity to find the relative velocity.

There is no doubt, but how to calculate x/y of the atmosphere (rotating frame) in the satellite reference frame (inertial frame)?
I know that the atmosphere rotates with speed (with an adequate accuracy for me):
Vrot= (6378.137 + alt_satellite) * (2 * PI) / 86162 * cos(lat_satellite) [km/s]
the z component is always 0, but how to calculate x/y components?
 
##\vec v = \vec r \times \vec \omega## with the cross product.
 
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