The Guide provides comments and various options, so that an ordinance can be tailor made to fit the local needs. The issue instead should be whether people are for safe, task-effective lighting or for lighting that is less effective, wasteful and sometimes even dangerous. Since late December, the Sun has been moving northward along ecliptic and, on March 20 th , it will cross over the celestial equator, bringing spring to the Northern Hemisphere. This event is known as the vernal, or spring, equinox . The word equinox means equal night and is used to denote the nearly equal lengths of day and night that occur on this day.
Spring brings with it warmer, longer days and, much to the chagrin of astronomers, shorter nights.
The answer can be found by examining the Earth's axis of rotation , which can be depicted as a line drawn through the Earth from pole to pole. This line, the Earth's axis of rotation, is tilted at an angle of about 23.5 degrees from the Earth's orbital plane. When we look at the night sky the celestial equator is slated by the same angle, 23.5 degrees, when compared to the ecliptic. So, all this tilting and spinning and orbiting results in the seasons and causes the Sun to appear to move slowly along the ecliptic, crossing the celestial equator on March 20th this year. As we venture outside during these warmer, shorter nights, we notice that the Milky Way is slipping away toward the horizon, taking with it many of the bright winter constellations.