m.e.ash   sept 1965    subroutine lunorb
determination of position,velocity,acceleration in browns mean
lunar orbit and the partial derivatives of these quantities with
respect to initial mean orbital elements

jd = julian day number (jed of noon on given day)
fract= fraction of day from midnight
nn = 0 position,velocity,acceleration determined
nn = 1 position,velocity,acceleration and partial derivatives
of position,velocity,accelertion determined
nn =-1 position,velocity,acceleration and partial derivatives
of position,velocity determined

ylun(i),i=1,9 position,velocity,acceleration in mean lunar
orbit
dylun(i,j), i=1,9, j=1,6  partial derivatives of position,
velocity,acceleration in mean luar orbit
with respect to initial mean orbital elements

partial derivatives w.r.t. initial inclination, ascending
node, perigee relative to mean equinox and equator of ref. epoch
calculated by substituting the derivatives of the B matrix for
the original B matrix