Stand in an open area outside so that your shadow falls on the ground rather than on a wall. Have a friend or family member measure the length of your shadow. Your shadow will be longer in the morning and evening and shorter in the middle of the day. To determine the time, use the Personal Sundial chart to get the length of your shadow. This method isn't as accurate as using an official clock, but it works well enough for telling time during daylight savings time when your shadow is long at the start of spring and short in the fall.
Here's how: Divide the number of hours your shadow is long by seven and then multiply this number by four. For example, if your shadow is 9 feet long at 10 a.m., then it's about 1,800 inches long. 7 x 18 = 126, which is close to 12 noon. If you follow these steps, you'll know what time it is even without looking at a watch.
You can also use this method to figure out what time it is during other parts of the day. Just measure your shadow at different times of the day and you'll know what time it is everywhere you go.
Finally, you can use your shadow to make sure you set your alarm clock correctly. Measure your shadow early in the morning before you go downstairs. If it's too short, set your alarm for earlier; if it's too long, wait until later.
You can tell the time by the length of your shadow. Then refer to the Sun's position in the Sky Map or Sun Sign Chart.
For example, it is morning in Los Angeles when the sun rises due east and sets west-southwest. Therefore, its shadow is long during the morning and short during the afternoon.
In New York City, which has a similar climate to LA, its morning and evening shadows are also long but its midday shadow is only slightly longer than in LA.
In London, whose summer days are shorter but still warm, the sun rises north-northwest and sets south-southeast, so that its shadow is about the same length at all times of day.
In Chicago, whose winter days are cold but not dark, the sun rises due north and sets southwest, so that its shadow is almost as long at noon as at dawn.
In Honolulu, whose summer days are hot and sunny, its sun rises northeast and sets northwest, so that its shadow is shortest at sunrise and longest at sunset.
Because your shadow stretches sideways, it seems longer on the ground. The sun is at its greatest position in the sky by lunchtime. When the sun is directly above you, its light shines down on you, creating a small shadow. This is called direct sunlight.
When the sun is over the horizon but not yet above you, its light hits the ground first, and then travels up toward the sky. At midday, the sun is at its highest point in the sky, so there is no difference between night and day for you. You would use exactly the same techniques to observe the moon during this time as you do at night.
As the sun gets lower in the sky, its light will start to touch the ground first, and then rise up toward the sky. By late afternoon, the sun is low in the sky, so there is more daylight left after you finish observing. You would use exactly the same techniques at this time of day as you do at night.
At sunrise and sunset, the shadow of your body falls to the west or east of you, depending on which way you are facing. Because the Earth is rotating, at any given moment people in different parts of the world are seeing different things: A person in Asia might see a sunset while someone in North America sees one only just beginning.
The length of the ensuing shadow is determined by the position of the sun in the sky. Move your mouse pointer over the time symbols to pause the animation at that specific point. Here's a useful suggestion: Go outside the next time it's sunny and take a careful look at your own shadow. You'll see that its length varies depending on how far away you stand from the light source.
Shadows become longer when there is more sunlight and shorter when there is less sunlight. During a solar eclipse shadows are completely absent because the moon is blocking out the light from the sun. Shadows also vary in length based on the height of the object casting the shadow. For example, if you were to stand next to a large building with high ceilings then your shadow would be much longer than if you were standing in an open field. Objects that cause shadows are called "shadow-makers." The term "shadow-catcher" is used for objects that interact with shadows such as people, animals, and buildings.
In physics, the word "shadow" describes an effect caused by a massive body like Earth blocking out part of the light from a distant object like a star. As light travels through space it is bent or curved around Earth. This has important effects for planets like ours that have surface features like oceans and continents. If a planet had no surface features then its shadow would fall directly over its center and provide evidence of its presence.
Because of the location of the sun, your shadow will be different at different times of the day. Because the sun is above you at midday, your shadow is tiny. Your shadow will be lengthy in the morning and evening. The length of your shadow is determined by two things: how far away you are from the light source and the angle at which you stand with respect to the light.
Shadows become darker when sunlight hits them. This is because dark objects stop more light than bright objects. So if something is dark enough, all of its surfaces will behave as if they were black. Light would not be able to get through, even though some does get through as long as it's not too much light. So if you put dark objects next to lights, they will get lighter instead of lighter like bright objects do. This is because lights remove light from shadows. So if you have a shadow puppet show, you will see that shadows get darker when the sun goes down.
Shadows can also appear darker at night time if you are standing near a window or outdoor lighting object. During the day, these objects block out most of the sunlight, but at night time, they let in light that other objects don't let in during the day. This makes the object look like it's giving off more darkness than it actually does.
You must first wait for the sun to set in order to acquire an accurate reading on your direction utilizing shadows. Mark the location where your sun rod casts its first shadow when the sun rises in the morning. This shadow will always point west, no matter where you are on the planet. Make an east-west line. From left to right, stop at the point where you see a shadow cast by something that is still. That thing may be another stick or it may be the ground. If it's not the ground, then there is land north of you and south of you. They intersect at the point where you stopped drawing.
Now, return to your starting point and repeat this process in the evening when the sun goes down. The object's shadow will point back towards its source (east) when measured from both points. See if you can locate yourself using only these two shadows.
If you were to do so on average streets you would find that the west-east line passes through the middle of town, while the north-south line falls near the border with another state sometimes many miles away. These are called "meridianal" lines and all compass directions lie between them. Directions to anywhere on Earth can be found by rotating the map until one of these lines is aligned with the nearest city landmark such as a mountain or river. At that point, the direction you are pointing toward will be indicated by a small arrow on the map.