A sun dial works by casting a shadow that is determined by the sun's position in the sky. Sun dials come in a variety of styles and shapes. Cheap, mass-produced sun dials often have design flaws that prevent them from accurately showing the time.Know More
Locate true north. This is different from compass north, which is affected by the Earth's magnetic pole. GPS systems have a setting for true north. A combination analemmatic-horizontal sun dial is self-orienting. You stick a pin in today's date and turn it so that both sundials show the same time.
Solar time and standard time may be as much as 16 minutes apart because the number of hours of sunlight varies while the length of a day is always 24 hours. You can adjust solar time to standard time by consulting the Equation of Time chart, which is included with some sun dials.
Look for the edge of the shadow that's furthest from the gnomon (pronounced no-mon). This shadow line should be straight from the center of the sun dial to the periphery. If the time is near solar noon, there may be a bend in the line. In this case, use the outermost part of the shadow. Morning times appear on the left side of the center meridian, while afternoon hours are on the right.
When a ring appears in the sky around the sun, it is called a halo. Halos have also been observed around the moon in the night sky.Full Answer >
Earth's seasons are determined by the angle at which the sun passes through the sky each day. During summer, the sun rises higher in the sky and more sunlight reaches the surface, but during winter, the sun passes closer to the horizon, spends less time in the sky and imparts less energy to the ground. The relative angle of the sun is determined by the tilt of the Earth.Full Answer >
Jupiter is visible without a telescope and is the fourth-brightest object in the sky after the sun, the moon and the planet Venus. It is three times brighter than the brightest star, Sirius.Full Answer >
Ra, the ancient Egyptian god of the sun, controlled the passage of the sun across the sky. Most paintings of Ra show a man with the head of a hawk, but other representations include a man with the head of a beetle or ram.Full Answer >