ngo=1 planet-asteroid integration (obsolete)
ngo=2 moon integration (obsolete)
ngo=3 satellite-probe integration (called by subroutine planet)
ngo=4 n-body integration (called by subroutine planet)
ngo=5 earth rotation integration
ngo=6 moon rotation integration (obsolete)
ngo=7 planet rotation integration
ngo=8 moon orbit and rotation integration

-------note that the changes made to the royal road integrator by --
-------r. king in may 77 to fix the truncation problem on the 370/470--
-------machines did not restore completely the lincoln 360/67 precison
-------and that the adams-moulton integrator should be used----------