Twilight in the morning and evening means that it will be light for a few minutes before and after the times listed. The rate of change of daylight is variable, and depends upon the time of year and the latitude of the area the distance from the equator. So, for example, the rate of change is slowest around the solstices the beginning of winter and summer, in December and June and fastest around the equinoxes the beginning of spring and fall, in March and September.
The following daylight calculator can be used for guidance:. Calculator in part based on formulae in the book Astronomical Algorithms by Jean Meeus. Results assume an unobstructed view of a planar horizon. Your current location and time zone have likely already been detected. The color diagram gives a rough depiction of how the color temperature of sunlight transitions between each of the marked times, presuming clear skies.
Depiction of light as the day progresses from midday to dusk or reverses towards dawn. For locations near the poles, the above representation may no longer be representative. Note how the contrast, direction and color temperature changes the appearance of the sphere as the day progresses.
For more on types of light, also refer to the tutorial on natural light in photography. What we really see during sunrise and sunset is the sun's apparent position — not its actual position. The apparent position is determined by how the sun's image gets refracted as viewed through the atmosphere, similar to how objects underwater appear shifted relative to their actual position.
The further you live from those exact coordinates, though, the more drastically your local sunrise and sunset times might differ from the published times.
Longitude lines are the imaginary lines that run vertically around the globe, intersecting at the North and South Poles. Longitude is a way of talking about how far east or west a location is in relationship to one specific imaginary line, called the Prime Meridian, that runs through the town of Greenwich, England. Because the Earth spins clockwise, the Sun appears to the east of any given location each day.
In addition, not all of us live right at the easternmost edge of our respective time zones. The further west you live within your time zone, the later your sunrise will be.
There is a simple, but somewhat inexact, way to figure this out. For every 70 miles you travel west within your time zone, sunrise will be about four minutes later. This time decreases somewhat the further you move from the Equator, though. Latitude lines are imaginary lines that encircle the globe horizontally. Latitude is a way of talking about how far north or south a location is in relationship to the Equator, the imaginary line that runs around the center of the globe.
Unlike longitude lines, latitude lines never intersect. While equatorial locations get approximately 12 hours of daylight and darkness each day, year-round, areas closer to the North and South Poles can experience several months of constant sunlight or darkness at a stretch. Most North Americans live somewhere between these two regions. Generally speaking, the higher your location is, the earlier the Sun will rise, and the later it will set, compared to when it would for the same location if it were at sea level.
An easy way to determine what effect altitude has is to remember than sunrise will be one minute earlier for every mile of altitude, and that sunset will be later by the same amount.
To find your exact location coordinates, try this finder. If your longitude is very close to one of these, then luck is with you, and you can use our printed times for the rising and setting of the Sun and Moon without any correction. Mars Hill, Maine , experiences the earliest sunrise in the contiguous United States, with the Sun coming up at a. Mars Hill is not always the first place to see the Sun year-round, though. The earliest sunset of the year happens in Bar Harbor, Maine , where the Sun goes down at p.
Fortuna, North Dakota , which sits far to the west of much of the rest of the Central Time Zone, bears the distinction having of both the latest sunrise and sunset of the year in the contiguous U. There, the sun rises at a. Of course, Fotuna is not the last place in the U. That happens in Cape Flattery, Washington , the northwesternmost point in the contiguous U.
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