<P> In the Northern Hemisphere, the winter sun (November, December, January) rises in the southeast, transits the celestial meridian at a low angle in the south (more than 43 ° above the southern horizon in the tropics), and then sets in the southwest . It is on the south (equator) side of the house all day long . A vertical window facing south (equator side) is effective for capturing solar thermal energy . For comparison, the winter sun in the Southern Hemisphere (May, June, July) rises in the northeast, peaks out at a low angle in the north (more than halfway up from the horizon in the tropics), and then sets in the northwest . There, the north - facing window would let in plenty of solar thermal energy to the house . </P> <P> In the Northern Hemisphere in summer (May, June, July), the Sun rises in the northeast, peaks out slightly south of overhead point (lower in the south at higher latitude), and then sets in the northwest, whereas in the Southern Hemisphere in summer (November, December, January), the Sun rises in the southeast, peaks out slightly north of overhead point (lower in the north at higher latitude), and then sets in the southwest . A simple latitude - dependent equator - side overhang can easily be designed to block 100% of the direct solar gain from entering vertical equator - facing windows on the hottest days of the year . Roll - down exterior shade screens, interior translucent - or - opaque window quilts, drapes, shutters, movable trellises, etc. can be used for hourly, daily or seasonal sun and heat transfer control (without any active electrical air conditioning). </P> <P> Everywhere around the world during the equinoxes (March 20 / 21 and September 22 / 23) except for the poles, the sun rises due east and sets due west . In the Northern Hemisphere, the equinox sun peaks in the southern half (about halfway up from the horizon at mid latitude) of the sky, while in the Southern Hemisphere, that sun peaks in the northern half of the sky . When facing the equator, the sun appears to move from left to right in the Northern Hemisphere and from right to left in the Southern Hemisphere . </P> <P> The latitude (and hemisphere) - specific solar path differences are critical to effective passive solar building design . They are essential data for optimal window and overhang seasonal design . Solar designers must know the precise solar path angles for each location they design for, and how they compare to place - based seasonal heating and cooling requirements . </P>

In the middle latitudes of the northern hemisphere on june 22 the sun