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year month day hour minute 197019711972197319741975197619771978197919801981198219831984198519861987198819891990199119921993199419951996199719981999200020012002200320042005200620072008200920102011201220132014201520162017201820192020 010203040506070809101112 01020304050607080910111213141516171819202122232425262728293031 000102030405060708091011121314151617181920212223 : 000102030405060708091011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859   Time zone GMT-12GMT-11GMT-10GMT-9GMT-8.5GMT-7GMT-6GMT-5GMT-4GMT-3.5GMT-3GMT-2GMT-1GMT 0GMT+1GMT+2GMT+3GMT+3.5GMT+4GMT+4.5GMT+5GMT+6GMT+6.5GMT+7GMT+8GMT+8.75GMT+9GMT+10GMT+10.5GMT+11GMT+11.5GMT+12 DST
Format: degrees decimal coordinate
[-]deg.dddddd , [-]deg.dddddd     coordinate location 41° 53´ 25.008" N 12° 29´ 32.928" E

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SunRise SunSet Calendar

sun position	Elevation	Azimuth	latitudes	longitudes
07/09/2010 * 02:42	-30.54°	45.86°	41.89028°	12.49248°
twilight	Sunrise	Sunset	Azimuth Sunrise	Azimuth Sunset
twilight -0.833°	05:41:36	18:33:52	81.02°	278.71°
Civil twilight -6°	05:13:14	19:02:05	76.21°	283.48°
Nautical twilight -12°	04:39:32	19:35:40	70.28°	289.37°
Astronomical twilight -18°	04:04:28	20:10:33	63.73°	295.86°
Daylight	Today	Tomorrow	Yesterday	Noon
07/09/2010	12:52:16	-00:02:45	00:02:43	12:07:44

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back to Top     Contents     Chart1    Data    Table    Chart2

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Contents

  Sun Position

  Sun chart

  Daylight

  Date

  Format

  Comment

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Sun Position

Calculation of the position of the sun's position in the sky at one point on the earth at a particular time of day. The calculated data are: solar angle of zenith and declination angle, the time of rise set and noon, the daylight with the difference from the previous and later day. It also displays graphs of the solar path.
Sunrise and sunset are defined as the instant when the upper limb of the Sun’s disk is just touching the horizon, this corresponds to an altitude of -0.833° degrees for the Sun.
Twilight is the time after sunset characterized by a diffuse light (by extension the morning twilight, use term aurora, dawn or sunrise).
Civil twilight lapse of time between sunset and when the sun reaches the elevation height of -6°, in the sky are visible only a few stars and planets particularly bright.
Nautical twilight represents the time the Sun takes a pass from -6° to -12° below the horizon, in this period are distinguished horizon line and the main stars.
Astronomical twilight is the time interval between sunset and when the sun reaches 18° below the horizon, the sky is dark, is possible to distinguish the stars up to the sixth magnitude.
Noon in solar time occurs when the sun is at its highest point in the sky for the day, and it is either due south or due north of the observer depending on the latitude.
Azimut indicates an angle between a point and a reference plane. Generally is the angular distance of a point from the North.
The height, or Eelevation , is the angular distance of the horizon a point on the celestial sphere, measured as positive if facing the Zenith, and negative if directed towards the Nadir.
Zenith , is the intersection perpendicular to the plane of the horizon passing through the observer with the visible celestial hemisphere and is the point above the head of the observer. The diametrically opposite point is called Nadir.
The knowledge of the position of the sun and the daylight hours, allow to know the energy radiated from the Sun (renewable) at the point on the Earth that we are examining.
The solar energy can be heat engines produced from solar panels or electrical produced by photovoltaic panels.

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Sun chart

Sun path charts can be plotted either in Cartesian (rectanglar) or Polar coordinates.
Cartesian coordinates where the solar elevation is plotted on X axis and the azimuth is plotted on the Y axis.
Polar coordinates are based on a circle where the solar elevation is read on the various concentric circles, from 0° to 90° degrees, the azimuth is the angle going around the circle from 0° to 360° degrees, the horizon is represented by the outermost circle, at the periphery.
The azimuth angle indicates the direction of the sun in the horizontal plain from a given location. North is defined to have an azimuth of 0° and south has an azimuth of 180°.
The various trajectories of the sun’s in the sky are bounded by those of the 21st day (equinox) of each month from December 21 until June 21.
We plot the time, on the hour, for all hours during which the sun is in the chart.

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Daylight

The length of day is the time interval between sunrise and sunset, so the time period in which we can observe the direct sunlight.
The duration depends on the latitude, the longitude, altitude above sea level (more high and more great the length of day) and obstacles horizon.
The algorithm uses the altitude 0 meters.
The transition from day to night is not clear before and after there is a period of scattered light (twilight), where you can still see, the phenomenon is due to reflection (down) of light by the atmosphere that it’s over to our point of observation.

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Date

Year Month Day
Are the date, the values are selectablly by combo, the default is today.
Hour : Minute
Are the time, the values are selectablly by combo, the default is now.
Time zone GMT
Greenwich Mean Time, identifies the time zone of reference of the Earth. If we divide the 360° for 24 to obtain a 24 parts every 15° longitude, in reality the area is bounded by national borders.
DST
Daylight saving time, clocks are adjusted forward one hour near the start of spring and are adjusted backward in autumn.

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Format

Value range

   Valid value for the latitude are from -90.0° to 90.0° for the longitude are from -180.0° to 180.0°, the + sign should be omitted, while the minus sign is not necessary if there is a radio component to select the direction N-S or W-E (Degree and Decimal format).

Decimal

   You have to select a direction (N-S or W-E) and insert a number from 0 to 90 for the latitude or from 0 to 180 for the longitude (example 45.12345).

Degree

   Degree format is conposed of direction (N-S or W-E) and three sets of numbers separate by the symbols for degrees (°), minutes (’), and seconds (").
   Degree is a integer value without sign, from 0 to 90 for the latitude or from 0 to 180 for the longitude. Minute is a integer value without sign, from 0 to 59. Seconds is a double value without sign, from 0 (or 0.0000) to 59.9999 .

Coordinates

   Coordinates format is the pair of latitude and longitude, with sign minus (-) for the direction south latitude and west longitude separate by comma simbol (,), here some example:
     52.5163 , 13.3779
     40.7682 , -73.9816
     -22.9708 , -43.1830

Search on map

   Click on search to open the webpage Earth Coordinate, here you obtain the latitude and longitude simply by clicking on the map, and save the value by the button save.

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Comment

If detected inaccuracies bug, want to suggest new features or simply express your opinion of the site web add a comment.
Thanks in advance for your contribution to improve this site.

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