Anywhere on or close to the equator.
At the north and south poles . . . all the time Everywhere else . . . on the occasion of the equinoxes, March 21 and September 21.
It doesn't have a velocity! However, in theory, one could say that darkness is the only thing that replaces light!! So as light goes away, darkness takes its place!! So darkness probably travels at the speed of light :D - 186000 miles per second (that's about 7.5 times round the earth in a second)
Light-hours?
If you're in the dark, seek for light; If you're in the light, seek for brighter light; never seek for darkness, coz if you do, it's what you'll gonna get.
No. The hours of darkness and day light are equal during autumnal equinox. (Both 12 hours)
On a solstice, it is only at the equator that the hours of light and dark are equal. At other parts, they would be different with one of the Poles experiencing 24 hours of daylight and the other Pole experiencing no daylight. If it is the June solstice, then it is the North Pole with 24 hours of daylight and the South Pole with none, while it is the opposite in the December solstice. It is at the equinox that the amount of daylight and darkness hours are equal around the world.
In terms of daylight and darkness, that will depend on where in the world you are. If you are in the Antarctic, then it is bright all of the time, with no darkness, in January and completely dark with almost no light in July. It would be the reverse in the Arctic. If you were on the equator, it would be about 12 hours of light and 12 hours of darkness all year. Between the equator and the poles, the amount of darkness and daylight will vary, getting more extreme the closer to the poles you get.
Twilight.
As it is the month of an equinox, there is a fairly equal amount of darkness and light, so about 12 hours of daylight.
Darkness is only the absence of light. The 'speed of darkness', or the speed at which darkness 'propagates' (even though only the absence of photons is propagating) is therefor equal to the speed of light.
Anywhere on or close to the equator.
At the north and south poles . . . all the time Everywhere else . . . on the occasion of the equinoxes, March 21 and September 21.
The equinox is the point in time where the Sun crosses the equator and there is no tilt to the Earth, thus there are approximately the same number of hours of light and darkness in both hemispheres. The term "equinox" comes from the Latin aequus (equal) and nox (night).
The equator.
No, light is not the absence of darkness. Darkness is nothing, light is something.No, light is not the absence of darkness. Darkness is nothing, light is something.No, light is not the absence of darkness. Darkness is nothing, light is something.No, light is not the absence of darkness. Darkness is nothing, light is something.
Yes, some part of the planet Jupiter is always in sunlight, although very little sunlight is able to penetrate past the upper cloud level. Jupiter has a day length of 9.84 hours. On the equator, 4.92 hours would be spent in light and 4.92 hours would be spent in darkness.