21. The equation of time is constant only for a planet with zero axial tilt and zero orbital eccentricity. 22. :: The " equation of time " represents the difference between local mean time and local solar time. 23. As explained in the equation of time article, this is due to the obliquity of the ecliptic ). 24. This correction which may be as great as 15 minutes is described by the equation of time . 25. The east west component shows the equation of time , or the difference between solar time and local mean time. 26. The excess half turns are removed in the next step of the calculation to give the equation of time : 27. To lazy to dive into this subtlty I decided that the Equation of Time article explains this well enough. 28. This correcting value is given in tables and known as Equation of time ( see there for details ). 29. These usually have hour lines shaped like " figure eights " ( analemmas ) according to the equation of time . 30. Machines such as solar trackers and heliostats have to move in ways that are influenced by the equation of time .
