Angular diameter result confirmation Not being a math-minded person at all, however basic it might appear to be to all of you in this particular question, I would like to get the following calculation confirmed.
I'm trying to calculate the angular diameter of two natural satellites orbiting a planet, as seen from the planet.

Satellite A is located 568350 km from the planet and has a diameter of 4400 km.
Satellite B is located 357094 km from the planet and has a diameter of 1900 km.

For Satellite A, we would therefore get:
$$\arctan\left(\frac{4400}{568350}\right)=0.44^\text{o}$$
For Satellite B, we would therefore get :
$$\arctan\left(\frac{1900}{357094}\right)=0.3^\text{o}$$
Similarly, for our moon, the same calculation goes as follows:
$$\arctan\left(\frac{3476}{384402}\right)=0.51^\text{o}$$
To find the angular diameter of a satellite you need to find
$$\arctan\left(\frac{\text{diameter of satellite}}{\text{distance to satellite}}\right)$$
As you have been using the diameter of the planet, your formulae are wrong.
You should also make use of the small-angle approximations $\arctan(x)\approx x$ for small x in radians. So to get the value in degrees you can do
$$\frac{180^\circ\times\text{diameter of satellite}}{\pi\times\text{distance to satellite}}$$
And you should round your values. You don't need 15 significant figures of accuracy!