Table of Contents
Does the sun move anticlockwise in the Southern Hemisphere?
In the Southern Hemisphere, these directions are reverse. When we are standing on the Southern Hemisphere, the Sun and its shadows seem to be moving round the Earth anti-clockwise, since the Earth there seems to be spinning clockwise, as they are upside down!
Why is my sundial going backwards?
The answer is because of an (understandable) northern-hemisphere bias. As all shadows point northward in the northern hemisphere, the shadow of vertical stick moves across the northern arc, not the southern arc, of a crude sundial.
Which direction should a sun dial face?
Sundials need to point in the direction of True North, and the style (either a sharp straight edge or thin rod, often located at the edge or tip of the gnomon) must be aligned with the Earth’s rotational axis.
Is the sun in the south in the Southern Hemisphere?
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. The latitude (and hemisphere)-specific solar path differences are critical to effective passive solar building design.
Do sundials work in the Southern Hemisphere?
In the Southern Hemisphere A sundial at a particular latitude in one hemisphere must be reversed for use at the opposite latitude in the other hemisphere. A vertical direct south sundial in the Northern Hemisphere becomes a vertical direct north sundial in the Southern Hemisphere.
How do sun dials work?
A sundial contains a gnomon, or a thin rod, that casts a shadow onto a platform etched with different times. As the sun changes relative positions over the course of a day, the rod’s shadows change as well, thus reflecting the change in time.
How do you use a sundial in the southern hemisphere?
A sundial at a particular latitude in one hemisphere must be reversed for use at the opposite latitude in the other hemisphere. A vertical direct south sundial in the Northern Hemisphere becomes a vertical direct north sundial in the Southern Hemisphere. To position a horizontal sundial correctly, one has to find true North or South.
Why does a sundial Go Round the same way as a clock?
Clocks were invented in the Northern hemisphere and were made to go round the same way as sundials. The shadow on a sundial in the Northern hemisphere goes round clockwise because of the way the sun goes round in the sky.
Why do dials go clockwise?
This is why all dials of any type usually go clockwise. Shadows go “clockwise” only for people in the northern hemisphere. In the southern hemisphere everything is reversed; the shadows go counter clockwise.
What is the angle of a vertical sundial?
sundial makes an angle of 90°–L with the vertical (that is, an angle L with the horizontal), as shown in the side view in Figure 5. Calculating the angle hours for the vertical sundial In the southern hemisphere, the vertical dial is north-facing. Unlike the equatorial dial, the hour angles are not equally spaced. In Figure 6,