At a given location and day of the year, the times of sunrise and sunset do not remain constant. This is because our measurement of time goes a little farther awry until corrected each leap year. Every four years the times should be about the same. Why is mid-August the hottest time? 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. Its latest sunrise occurs at a. Two other U. Ontario, Oregon , in the Mountain Time Zone, sees its latest sunrise at a. Ontonagon, Michigan , in the Eastern Time Zone, has its latest sunrise at a.
Of course, all of this pales in comparison to Barrow, Alaska , where the Sun stays down from November 20 until January 22, and stays up from May 12 until August 1 each year! A bit further south in Anchorage , mid-winter days are only five and a half hours long.
The Sun comes up at a. Jaime McLeod is a longtime journalist who has written for a wide variety of newspapers, magazines, and websites, including MTV. If you imagine looking down on the solar system from above, the Earth rotates counterclockwise on its axis and also revolves in a counterclockwise orbit around the Sun. It's pretty easy to see that the rotation itself makes the Sun appear to move from East to West every day, but the revolution part is a bit trickier.
We'll start with a specific location, say New York City, facing towards the Sun and put the Earth at 12 o'clock on our imaginary clock face. In an intermediate position, when the Earth is at 9 o'clock, NYC is at the bottom of the globe. If you think for a moment about the relative position of the two bodies you can see that the Sun seems to be moving from West to East.
Since the Earth's yearly revolution is a slower effect than its daily rotation, this eastward contribution is small but has an important effect, causing the Sun to appear at its highest point in the sky a few minutes later each day. The Earth's axis of rotation is also tilted The Sun appears to trace a path across the sky from East to West, but that path shifts throughout the year. On the dates of the spring and fall equinox, the Sun rises due East and sets due West, but on the upcoming winter solstice it will be following its southernmost arc just as at the summer solstice it will be at its northernmost point.
Prior to the winter solstice, the Sun's eastward motion makes sunrise later but the southward motion makes sunset earlier. Around December 8th we reach the earliest sunset but sunrise continues to get later, aided by the southward motion.
At the solstice the Sun begins to reverse its North-South motion and start heading northward again.
0コメント