**Astronomical
Computations**

This tab screen has functions to convert Astronomical Units to Time of Light, Star Magnitude sums/differences and ratios. The Equation of Center calculates C, velocity, and r/a ratio. The velocity and Length of Orbit takes A-Major Axis, B Minor Axis, r- mean radius and e-eccentricity and calculates the approximate Orbit Length, the Perihelion Velocity and Mean Velocity. The final two frames are for converting any one Hours:Minutes:Second inputs to Hours Minutes and Seconds exclusive of what was entered. The last on is similar to the last except it is for Degrees:Minutes:Seconds and also add decimal degrees. Meeus always like to add coefficients in values like 1746' of arc. So it was extra work to be doing all the conversions all the time to proof.

The **Star Brightness** allows the
computation of stellar magnitude difference to Brightness ratio and also the Combination of Combined or Determination
of Singular from combined and one absolute magnitude. Enter either the Star Magnitude difference or the Brightness
ration and press “Calculate” to compute the other. For the other calculation
enter either the two separate star brightness entries or one star brightness and
the combined star brightness and it will calculate the missing component.