delta_t()
function to generate a vector of
valueschanging the parameters of the galsat()
function to
UTC (earlier in ET)
new function delta_t()
returns the delta-T in units
of seconds
galsat()
adding date & time validation
adding comments for the R code
displaying a photo of Jupiter instead of a circle
hiding the moons that are behind Jupiter’s disk
galdraw()
visually shows satellites’
positionsgalsat()
calculates numerical positions
of Galilean satellites