answersLogoWhite

0


Best Answer

This happens at both the vernal and autumnal equinoxes.

The equinoxes are the points in the earth's orbit of the sun when the Sun is positioned directly over the Earth's equator. This only happens twice a year because the earths axis of rotation is inclined approximately 23.44° from the plane of the orbit round the sun. Thus when the north pole is pointing at the sun the south pole is permanently in darkness and at the other end of the orbit when the south pole is pointing at the sun the north pole is permanently in darkness - this gives us summer and winter.

Now when the earth is 1/2 way between summer and winter positions (a day in spring and autumn) the axis of rotation is not pointing at the sun at all which means that both the north and south poles are illuminated evenly and each get 12 hours of daylight and 12 hours of night. This happens all over the planet and is the day of the equinox equinox.

User Avatar

Wiki User

16y ago
This answer is:
User Avatar
More answers
User Avatar

Wiki User

9y ago

Even though the word equinox means â??equal nightâ?? in Latin, it isn't entirely true that day and night are exactly the same on the equinox all over the world, just almost. The equinox day actually lasts a little longer than 12 hours. However, at the equator, the day and night stay approximately the same length all year round, even if the day will always appear longer than 12 hours, due to refraction.

This answer is:
User Avatar

User Avatar

Wiki User

9y ago

The Earth is tilted on its axis by about 23.44°. As it orbits the Sun sometimes it is tilted towards it and sometimes it is tilted away from it. In relation to the sun, those tilts are at maximum in June and December. As we are in early January, it is more tilted away from it, giving the northern hemisphere less hours of daylight, while the Southern Hemisphere has more, but each day that is changing. As we continue on our orbit, we come to two points when no part of the planet is tilted more towards the sun. These are the equinoxes. Earth is still tilting, but that tilt is now parallel to the sun. Earth is tilting forward, but the sun is either to its left or its right, depending on which equinox we are at. At that time, the lengths of night and day are more balanced around the planet. In March and September we have the equinoxes, halfway between solstices.

This answer is:
User Avatar

User Avatar

Wiki User

14y ago

At the "equinox"; "equi-" from "equal", and "nox" from the Latin word for "night". The equinoxes are generally on March 21 and September 21 each year, plus or minus one day because of the cycle of leap years. The US Naval Observatory has a web site for "Earth's Seasons" at which you can see the precise times of the solstices and equinoxes.

This answer is:
User Avatar

User Avatar

Wiki User

14y ago

At the equinoxes, day and night are approximately the same length. The equinoxes are the beginning of Spring (around March 21 in the northern hemisphere), and the beginning of Autumn (around September 23 in the northern hemisphere). I said "approximately" because day and night are not exactly equal, due to the diameter of the Sun, and refraction in the atmosphere. dummy

ITS EXUINOX

This answer is:
User Avatar

User Avatar

Wiki User

12y ago

These dates are called "equinox", from the Latin root "equi" for equal, and "nox" for night; "equal nights". Those dates are generally March 21 and September 21, although the dates may slide one day back or forward depending on the cycle of leap years.

But it isn't QUITE "equal"; on the equinox, the day is a little bit longer than the nights, because the Sun's light is refracted slightly AROUND the curve of the Earth by our atmosphere. When you see the Sun peek over the horizon, it is actually about 1 degree BELOW the horizon; but the light has been refracted or belt around the Earth by the atmosphere.

A:Neglecting atmospheric effects, the lengths of sun-up and sun-down are equal at

every place on earth at the time of the equinoxes ... March 21 and September 21.

A:The Autumnal and Vernal Equinox. A:Equal periods of sun-up and sun-down are all near March 21 and September 21,

everywhere on earth, including the equator.

A:Those days are often called the "equinoxes", but the equinoxes are actually the

points in the sky where the sun appears to be located on those days.

This answer is:
User Avatar

User Avatar

Wiki User

14y ago

The times of year when the days and nights are equal length is known as the equinox (literally means equal night).

For 2010 the Vernal Equinox is March 20th and the Autumnal Equinox is September 23rd.

This answer is:
User Avatar

User Avatar

Wiki User

12y ago

At the equinoxes, about March 21 and September 21. However, if you want to get precise, on the equinoxes the days are actually a little longer than the nights - because the Earth's atmosphere bends sunlight down and around the Earth. When we see the sunrise, the Sun is actually about a degree and a half below the horizon! And as the Sun is setting, the atmosphere bends the sunlight around keeping the day from slipping away for a few precious moments. So, on the equinoxes, the day length is actually about 10 minutes longer than the night!

The Earth's atmosphere does a better job of bending red light than blue light; that's why sunrises and sunsets are red.

This answer is:
User Avatar

User Avatar

Wiki User

14y ago

You could call it the "first day of Spring" or the "first day of Fall".

It occurs when the sun reaches either of the two points in the sky called the "equinoxes".

This answer is:
User Avatar

User Avatar

Wiki User

12y ago

Autumn equinox and spring equinox I believe...

This answer is:
User Avatar

Add your answer:

Earn +20 pts
Q: Why length of day and night is same in spring and autumn?
Write your answer...
Submit
Still have questions?
magnify glass
imp
Continue Learning about Astronomy

What is the order of the seasons of the year?

-- Spring-- Summer-- Autumn ("fall")-- Winter-- (repeat the list)The order is the same everywhere on earth.


How many hours of daylight does Autumn get?

That would depend on where you live, and which part of autumn you mean. The definition of "autumn" is the period between the autumnal equinox and the winter solstice, so the number of hours of daylight would be "less than 12, and decreasing". On September 22, the number of hours of hours of daylight would be only a minute or so less than 12 hours, while on December 19 the length of the day will be somewhere between 11.9 hours and zero, depending on your latitude.


When is Orion visible directly above the southern horizon?

Orion is visible during the early night during the winter. you look to the south and it should be there. by spring, it will be around the horizon(SSW-SW) at the same time(about 9-11 pm). in the summer, it's visible in the eastern sky just before sunrise. But you should see it again in Autumn, around NEN-E. All of this is from the perspective of North America.


What happens on September 21st?

On September 21st everywhere in the world has the same amount of sunlight. This also happens on March 21st. Also on the 21st of March and September the daytime and the nighttime are the exact same length.


In the northern hemisperethe sun reaches what equinox on March 20 or 21?

At the equinox day and night are of the same length all over the world because the Sun is in the plane of the Earth's equator, and that happens on March 21 and September 22 each year. At other times the Sun is above or below the Equator, and day and night have unequal lengths.

Related questions

What occurs on the vernal equinox?

Across the whole planet the day and night length are the same and it is the first day of Spring in the northern hemisphere and the first day of Autumn in the southern hemisphere.


What are solstices and equinoxes and how are they related to the seasons?

There are two solstices. they are the summer solstice (first day of summer), and the winter solstices (first day of winter An equinox is when day and night are the same length. like solstices, there are two of them. The Autumn equinox (first day of autumn), and then the spring equinox (first day of spring).


What are solstices and equinox how are they related to seasons?

There are two solstices. they are the summer solstice (first day of summer), and the winter solstices (first day of winter An equinox is when day and night are the same length. like solstices, there are two of them. The Autumn equinox (first day of autumn), and then the spring equinox (first day of spring).


What are solstices and equinox and how are they related to the seasons?

There are two solstices. they are the summer solstice (first day of summer), and the winter solstices (first day of winter An equinox is when day and night are the same length. like solstices, there are two of them. The Autumn equinox (first day of autumn), and then the spring equinox (first day of spring).


What are the seasons for Paris?

Same as anywhere else, Spring, Summer, Autumn, Winter. Spring and Autumn are the times to visit.


In what season are the days and nights roughly the same?

Day and night are roughly (but not exactly) the same at the equinoxes - first day of Spring, and first day of Autumn (Fall).


What is length of the day in a autumnal equinox?

During the Autumn equinox the length of the day and night are nearly equal. The length of the day on the equinox is approximately twelve hours.


What season does Argentina consider to be autumn?

Autumn. In the Southern Hemisphere, Autumn falls the same time of the year as our Spring.


What are the hours of daylight in autumn and in spring in Antarctica?

same as summer and winter!


What is the name given when the days and nights are the same?

Equinox is the name given when the day is made up of the same amount of day and night. There are two Equinoxes a year the Autumn Equinox and the Spring Equinox.


What kind of flower bulb has no leaves?

Nerines flower in Autumn and the leaves grow in Spring. The same applies to Autumn Crocus.


How many times per year do you have days in which the number of hours day and night equal what are the names of those days?

When night and day are approximately of equal length occurs twice per year. In the northern hemisphere these days are called the Vernal Equinox (20-21 March) and the Autumnal Equinox (22-23 September). However, as these seasons are reversed in the southern hemisphere, current usage is the March Equinox and the September Equinox.