Additionally, the days become a little longer at the higher latitudes those at a distance from the equator because it takes the sun longer to rise and set. Therefore, on the equinox and for several days before and after the equinox, the length of day will range from about 12 hours and six and one-half minutes at the equator, to 12 hours and 8 minutes at 30 degrees latitude, to 12 hours and 16 minutes at 60 degrees latitude.
The summer solstice occurs at the moment the earth's tilt toward from the sun is at a maximum. Therefore, on the day of the summer solstice, the sun appears at its highest elevation with a noontime position that changes very little for several days before and after the summer solstice. The summer solstice occurs when the sun is directly over the Tropic of Cancer, which is located at For every place north of the Tropic of Cancer, the sun is at its highest point in the sky and this is the longest day of the year.
The winter solstice marks the shortest day and longest night of the year. In the Northern Hemisphere, it occurs when the sun is directly over the Tropic of Capricorn, which is located at For a complete listing of the dates of the winter and summer solstices and spring and fall equinoxes through , check out this site from the U.
Naval Observatory. An alternative text link is found here. We all know that the Earth makes a complete revolution around the sun once every days, following an orbit that is elliptical in shape. This means that the distance between the Earth and Sun, which is 93 million miles on average, varies throughout the year. During the first week in January, the Earth is about 1. This is referred to as the perihelion. The aphelion, or the point at which the Earth is about 1.
This fact may sound counter to what we know about seasons in the Northern Hemisphere, but actually the difference is not significant in terms of climate and is NOT the reason why we have seasons.
Seasons are caused by the fact that the Earth is tilted on its axis by The tilt's orientation with respect to space does not change during the year; thus, the Northern Hemisphere is tilted toward the sun in June and away from the sun in December, as illustrated in the graphic below.
The Spring Equinox is the first day of spring season and occurs when the sun passes the equator moving from the southern to the northern hemisphere. The North Pole begins to lean toward the sun again.
Equinoxes do not always occur on the same day each year, and generally will occur about 6 hours later each year, with a jump of a day backwards on leap years. The Earth takes approximately Every 4 years, we have a leap year where another day is added to our calendar to make up for the 4 missing quarters. It is important to do this so that there is not a gradual drift of date through the seasons.
Solstice Seasons. Follow me on Twitter mbarrow. This site uses cookies. See our Cookie Policy for information. You may not redistribute, sell or place the content of this page on any other website or blog without written permission from the author Mandy Barrow. Time Zone by Mandy Barrow. Science index. Ideally, an Equinox should eliminate this, but this is not exactly true.
Equinoxes have been found to expose the Earth to approximately six or more minutes of daylight. This happens because of the Sun. The Sun is round and therefore unlike a straight beam of light from a flashlight, it cannot fully fade instantaneously. On average, you may notice most days or nights are extended by minutes. The extra light that exists is dependent directly on the season in which the Earth is experiencing. For the colder seasons, it is evident that night is longer while for the warmer seasons this is the opposite.
Equinoxes are naturally occurring phenomena of the Earth. These are only scheduled to happen twice a year. They occur because, at these times of the year, the equator is exposed to the constant rays of the sun as it crosses paths and sits above it. The Sun is only placed in this position when the orbit the earth follows, and the axial tilt synchronize or blend together. When this occurs, a line that divides the light and dark sections of the earth runs through the poles.
This line is termed the terminator, but you may know it as the twilight zone. You might wonder what prevents this from happening on most other days of the year. On a regular day within the year, the Earth is tilted at This allows the Earth to orbit with respect to the sun. This means that in the colder seasons of the Northern Hemisphere, there is less light leading to more night.
The opposite can then be said for the Southern Hemisphere, which is experiencing warmer seasons exposing it to more daylight. Equinoxes are evident two times of the year. The equinox, as discussed, only appears on occasions where the conditions are met between the Sun and the Earth. Since this is only occurring two times out of the year, then the date and conditions must be established. Also, note that the hemispheres receive the equinoxes on different dates according to their time zones.
However, they still take place simultaneously. Firstly, there is the autumnal, also termed the fall equinox. For the Northern Hemisphere, this occurs in September when the sun crosses the equator while moving south. This equinox is scheduled to occur in the fall, generally on or around September 22nd. The opposite can be said for the Southern Hemisphere as it experiences its equinox under a different title.
It is called the march vernal equinox or spring equinox. This equinox occurs in the Southern Hemisphere on March 20th. However, it can take place anywhere between the dates of the 19th and 21st. A solstice is characterized by the duration of time for which each hemisphere receives its day and night.
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