But it moved always as the sun moved, and just as regularly, giving a true measure of the solar day.
That the civil day has taken precedence of the solar day is shown by the recent legislation in regard to Summer Time.
But, of course, the length of the solar day is longer in the summer, giving more heat and more power.
Then it must follow that as the daily sections of the orbit vary in length, the time of the solar day must vary in length.
The latter are divided into sidereal hours, minutes and seconds as the solar day is.
The solar day is the fundamental unit of time, not only in daily life but in astronomical practice.
All the magnetic elements at any ordinary station show a regular variation in the solar day.
|solar day |
See under solar time.