To initiate orbital motion click on any of the icons in tool bar with red sign + or – , permitting also to speed or to slow planet motion by repeated clicking on them. ... Selecting Orbits item in menu bar and by subsequent choosing corresponding items in drop-down menu one can also fulfil the above actions. ... To enter new initial epoch or to change list of minor or major planets which are shown in the picture, select Orbits in menu bar and then select Input data in drop-down menu. ...