Are the days and nights equal at the equator all year round?

Question

Northern and Southern hemispheres have changing daytime lengths due to angle of earth to sun, but is it the same effect at the equator?

Answer 1

No days and nights are not of equal length all around the Equator due to the angle of the earth in relation to the sun.
The Equator is one of the Latitudes or imaginary circles drawn around the Polar Axis which, together with the lines of Longitude, form a grid on which the land and seas are mapped in a fixed geographical and astronomical position. This grid or chart is used to mark the position of the sun at midday to measure the length of a day.
Because the earth 's polar axis is at an angle to the earth's orbital trajectory the sun's light reaches the Polar regions for half a year at a time so we know that the earth tilts toward the sun for six months and away from the sun for six months.
Therefore every region on earth is exposed to varying degrees of sunlight throughout the orbit.
Every year, in the regions that get sunlight daily, there are two days, called the Equinoxes, when the hours of light and dark are equal. The Equinoxes move around the Latitudes at a rate of 0.98 degrees of Longitude per day, never occurring on the same day all around the Equator.
Regions around the equator do not tilt beyond the light of day in the same way as the Polar Regions do, so the effect of the Earth's tilt is not so apparent.

Answer 2

Length Of Day At Equator

Answer 3

How hilarious. After all the geniuses chimed in and said no, they are not equal length, I checked a sunrise/sunset chart for Quito, Equator, which is located smack dab on the equator. The savants were wrong. In June there are 12 hours and 6 minutes of daylight. In january, there are 12 hours and 8 minutes of daylight. So the answer is yes, there are equal amounts of daylight year round on the equator.
http://www.timeanddate.com/sun/ecuador/quito

Answer 4

Equal Day And Night

Answer 5

Theoretically speaking,
Since the "Circle of illumination" always cuts the Equator into two equal halves, The Equator will theoretically have equal lengths of days/nights, all year long.

(keeping affect of other factors constant)

Answer 6

Short, non pasted answer is no. It would be if the planet were level but the planet is tilted on its axis. So there are some seasonal changes in day length at the equator as Earth orbits the sun.

Answer 7

What a mess. I guess we need to ask God because people really don't know many correct answers.
http://home.earthlink.net/~eonnoe/IS_THIS_HELL.htm
Blessings until then... Bob

Answer 8

it depends...

Answer 9

Day and night are not equal to the equator all year round here is just a brief writing about the days and nights of the equator.



THE SUN, which is the fountain of light and heat, is placed in the centre of the universe; and the several planets, namely, Luna, ☽ (the moon); Mercury, ☿; Venus, ♀; the Earth, ⊕; Mars, ♂; Jupiter, ♃; Saturn, ♄; and Georgium Sidus [so named by its discoverer, Frederick William Herschel; it was later renamed Uranus]; move around him in their several orbs, and borrow from him their light and influence: on the surface of the sun are seen certain dark spots, but what they are is not known. They often change their place, number, and magnitude; and if they are really in the sun's body, as to all appearance they are, we must suppose that he moves around his axis in about twenty-five days and six hours; otherwise those various changes and alterations cannot be accounted for on the principles of reason and philosophy. The daily motion of the sun from east to west is not real; for, as I have observed before, the sun is fixed in the

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centre, and can have no motion but upon its own axis, that is, of turning round in the same space. The apparent motion, therefore, from east to west, must arise from the true and real motion of the earth on which we live, as I shall prove by and by. The body of the sun is so immensely large, that his diameter or thickness is computed to be 822,145 English miles [now known to be 865,000 miles, or 1,390,000 km], and a million of times larger than the globe of our earth; stupendous and amazing magnitude! which is supposed to be all fire, and by whose beams of light the whole system of beings about it is made visible.

The fixed stars which enamel and bespangle the concave expanse, or canopy of heaven, by numbers and lustre, make the night beauteous and delightful, which would otherwise be dark and horrible. The UNIVERSE has no determinate form or figure at all; for it is every way infinite and unlimited, and is called the MUNDANE SPACE, in which all worlds have their place and being.

The MOON, which is the next planet, or body, we are to consider, is, as to matter and form, not unlike our earth; for her body is uneven and spherical. The bright portions we see in her are the more prominent and illuminated parts of the land, as mountains, islands, promontories, &c. to which we are obliged for the light that is reflected to us; for the dark parts, which are supposed to be seas, lakes, vales, &c. are incapable of reflecting any light at all. Some of our philosopers [sic]

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assert , that there is an atmosphere of air about her; and, if so, then is the subject to the wind, clouds, rain, thunder, lightning, and other meteors [in the old sense of "atmospheric phenomena"], as well as the earth, and of consequence may be inhabited by men and animals. The diameter or thickness of the moon, is about 2175 English miles [now known to be 2160 miles, or 3476 km]. The moon revolves round the earth in about 27 days, 7 hours, and 43 minutes. According to the different position of the moon in her orb, with respect to the sun and earth, she puts on different aspects or phases, as new, horned, full, &c. And since, at the same distance from the sun, she never appears of a different face, it is evident that she has a diurnal motion round her own axis, which is completed in the same time as her periodical revolution is about the earth. So that the Lunarians, or people of the moon, (if there are such) have their days and months perpetually of equal length.

The other planets, i.e. Mercury, Venus, the Earth, Mars, Jupiter, Saturn, and the Georgium Sidus,* all revolve in the same manner about the sun as the centre of the system; and in the order from the sun as they are named in the following figure of the UNIVERSE.

* The Georgium Sidus is a later discovery, having two moons; without the orb of Saturn, and not represented in the following scheme, for want of room.

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Universe

The real motion of them all is from west to east, though sometimes they appear to move from east to west; and at other times seem not to move at all. And hence they are said to be direct, retrograde, and stationary. The Earth, Jupiter, and Saturn, are often eclipsed by the interposition of their respective moons, or satellites, between the sun and themselves; and these eclipses are sometimes partial, sometimes total, and sometimes central. The orbit of the earth (or the circle which the sun seems

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to describe round the earth), is called the ecliptic, which is divided into twelve equal parts, called signs, and are distinguished by the following names and marks, viz. Aries, the Ram, ♈; Taurus, the Bull, ♉; Gemini, the Twins, ♊; Cancer, the Crab, ♋; Leo, the Lion, ♌; Virgo, the Virgin, ♍; Libra, the Balance, ♎; Scorpio, the Scorpion, ♏; Sagittarius, the Archer, ♐; Capricornus, the Goat, ♑; Aquarius, the Water-bearer, ♒; Pisces, the Fishes, ♓.

There are many other things peculiar to the planets; but as they are not within the compass of my design, I shall pass them over, in order to speak more particularly of the earth.

Of the EARTH, considered as a PLANET.

THE Earth, by its revolution about the sun in 365 days, 5 hours, and 49 minutes, makes that space of time which we call a year.

The line, which the centre of the earth describes in its annual revolution about the sun, is called the Ecliptic.

The annual motion of the earth about the sun, is in the order of the signs of the zodiac; that is, from west to east.

Besides its annual revolution about the sun in the ecliptic, the earth turns round also on its own axis in 24 hours.

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The turning of the earth on its own axis every 24 hours, whilst it moves round the sun in a year, we may conceive by the rolling of a bowl [a ball used in lawn bowling] on a bowling-green; in which not only the centre of the bowl hath a progressive motion on the green, but the bowl, in going forward, turns round about its own axis.

The turning of the earth on its own axis makes the differences of day and night; it being day in those parts of the earth which are turned towards the sun; and night in those parts which are in the shade, or turned from the sun.

The annual revolution of the earth in the ecliptic is the cause of the different seasons, and of the several lengths of days and nights, in every part of the world, in the course of the year.

If the diameter of the sun be to the diameter of the earth as 48 to 1, (as by some it is computed), the disk of the sun is above 2000 times bigger than the disk of the earth; and the globe of the sun is about 100,000 times bigger than the globe of the earth.

The distance of the earth's orbit from the sun is above 20,000 semidiameters of the earth; so that if a cannon ball should come from the sun with the same velocity it hath when discharged from the mouth of a cannon, it would be 25 years in coming to the earth.

We shall now consider the earth in another sense, and speak of the several divisions made by geographers.

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OF THE CIRCLES,

Which are used by GEOGRAPHERS to explain
the Properties of the NATURAL GLOBE.

You may suppose the following figure to be a globe or sphere, representing the earth. The outermost circle, marked with the letters A, D, B, C, is called the meridian; and on this circle the latitude is reckoned, either from C towards A or B, or else from D towards A and B.

The equator is the line C, D, which upon the globe is a circle, and is sometimes called the equinoctial: Upon this circle the degrees of longitude are reckoned, beginning at C, and counting all round the globe till you come to C again; and O is the middle of the world between A and B, which are the two poles thereof: A representing the North Pole, B the South Pole.

The circles E F, and G H, are called the Tropics, beyond which the sun never moves.

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Circles


The line G F, which upon the globe is a circle, is termed the Ecliptic, in which the sun is perpetually moving from G to F, and F to G again. When the sun is in O, he is then in the Equinoctial, and the days and nights are of equal length to all the world, except under the Poles. When he is at F, which is called the Tropic of Cancer, days are at the longest to all those who dwell under the North side of the Equator. When the sun is at G, which is called the Tropic of Capricorn, days are at the longest to all those dwelling on the South side of the Equator, and at the shortest to those on the North side.

The circles LM and I K are called the Polar Circles, because to those inhabitants who dwell under these circles, the longest day is

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24 hours; so that the sun sets not, but moves quite round their horizon. Thus much may suffice for the circles of the sphere; only note this, that every circle, whether great or small, is divided into 360 equal parts or degrees; so that a degree is no certain measure, but only the three hundred and sixtieth part of the circle; and these degrees are again supposed to be divided into sixty equal parts, which are called minutes. Now, therefore, if a circle which will reach round the earth be divided into 360 parts, then one of those parts is equal to a degree, which was looked upon by the ancients to be equal to sixty miles, and thus one mile was exactly equal to a minute.

Of the ZONES.

The Zones are certain tracts of land, whose boundaries are made by the circles before described, and are five in number, namely, the Torrid Zone; the Northern Temperate Zone; the Southern Temperate Zone; the Northern Frigid Zone; the Southern Frigid Zone. --- 1.The Torrid Zone contains all that space of land which lies between the circles E F and G H; for to those inhabitants who dwell betwixt the said limits, the sun, at some time of the year, becomes vertical, i.e. right over their heads. 2. The Northern Temperate Zone is all that space betwixt the circle E F, named the Tropic of Cancer, and the line L M, called the Northern Polar Circle; and to all the inhabitants within this compass, the

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sun, when in their several meridians, casteth their shadows directly north. 3. The Southern Temperate Zone is that tract of land which lies between the circular line G H, called the Tropic of Capricorn, and the Southern Polar Circle I K. To all the inhabitants within this space, the sun, when in their meridian, casteth their shadows full south. 4. The Northern Frigid Zone, is that part of the earth which lies between the Northern Polar Circle L M, and the North Pole at A; to all these inhabitants the sun, at a certain season, and when in the Tropic of Cancer, does not set, but moves in view quite round the horizon, casting their shadows every way. 5. The Southern Frigid Zone is that part of the earth which lies between the Southern Polar Circle I K, and the South Pole at B. To all the inhabitants within these limits, the sun, when in the Tropic of Capricorn, sets not, but moves in sight as before, casting their shadows also every way.

Of the CLIMATES.

The Climates are reckoned from the Equator to the Poles; under the Equator the day is always 12 hours long, and under the Polar Circles the longest day is 24 hours. Geographers make 24 climates between the Equator and each of the Polar Circles, because there are 24 half hours difference between the length of day under the Equator, and the longest day under the Polar Circle; so that any place where the longest day in that place is half an hour

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longer or shorter than that of another place, is of a different climate. The first climate begins at the Equator; the second where the longest day is 12 hours and a half; the third where it is 13 hours, and so on. There are in all 48 climates of hours, that is, four [sic] from the Equator to the Polar Circle, either Northward or Southward. Besides the aforesaid 48 climates of hours, there are 12 more, called climates of months, that is, six from each of the Polar Circles to the Poles. They are called climates of months, because the longest day in the end of the first climate is one whole month, the longest day at the end of the second two whole months, and so on.

Of LAND and WATER.

The whole globe of the earth is called terraqueous, consisting of two bodies, namely, Land and Water, which may be divided in the following manner, viz.

LAND into Continents, Islands, Peninsulas, Isthmuses, Promontories, Mountains.

1. A Continent is a large tract of land, comprehending divers countries, kingdoms, and states, joining altogether, without any separation of its parts by water, of which we have four, viz. Europe, Asia, Africa, and America.

2. An Island is a part of land encompassed round with water.

3. A Peninsula, called also Chersonesus, is a piece of dry land every where environed

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with water, save only a narrow neck of land adjoining the same to the Continent.

4. An Isthmus is that narrow neck of land which joins the Peninsula to the Continent, by which people go from one to the other.

5. A Promontory is a high piece of land, stretching out into the sea, the extremity whereof is commonly called a Cape.

6. A Mountain is a rising part of dry land, overtopping the adjacent country, and appearing the first at a distance.

WATER is divided into Oceans, Seas, Gulfs, Straits, Lakes, and Rivers.

7. Ocean is a vast collection of water, environing a considerable part of the Continent.

8. The Sea is a smaller body of water, intermixed with Islands, and for the most part environed with land.

9. A Gulf is a part of the Sea, every where encompassed with land, except only one passage, whereby it communicates with the main ocean.

10. A Strait is a narrow passage, either joining a Gulf to the neighbouring Sea or Ocean, or one part of the Sea or Ocean to another.

11. A Lake is a small collection of deep standing water, surrounded by land, and having no visible communication with the Sea.

12. A River is a considerable stream of fresh water, rising out of one, or various fountains, continually gliding along in one or more currents, till it empties itself into the sea or ocean.