Calculating the suns path in sky

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In summary, the individual is searching for equations to calculate the solar path and is trying to determine whether the degree values need to be converted to time values. They are also asking for clarification on the units used in the equations provided, specifically in regards to the equation of time which uses trig functions and gives the result in minutes. The provided link explains the units used in each equation. Additionally, the individual is seeking clarification on what is meant by "the Sun's path in the sky" and suggests that it may involve tracking right-ascension and declination or spherical-polar coordinates.
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dwn
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I've searched the internet and found a few sites, of varying depth, that contain some of the equations to calculating the solar path. At the moment, I'm not particularly concerned with precision. I am trying to discern the equations in order to implement them into a java program I am writing.

Some of the equations use degrees multiplied by time constants and so I'm trying to decide if I need to change the degree value to time values? The reason I ask is that my result is not a value I expected. The link provided has the series of equations I would like to use.

The equation of time uses trig functions, but says the result represents minutes. Does that mean I need to convert the degree value to minutes, or the result is already in minutes? No units are used in this case and so its a little confusing to discern.

http://www.pveducation.org/pvcdrom/properties-of-sunlight/solar-time
 
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You should start by saying what you mean by "the Sun's path in the sky".
Usually I would think of you tracking right-ascention and declination from a particular lat/long position on the Earth... but you may just be interested in tracking the spherical-polar coordinates from the center of the earth.

The web page you cite uses "minutes" for time but not for angles - it's pretty good at explaining which bit has what units.
The EoT formual gives the EoT in minutes ... but the angle B, as the following text explains, is in degrees.

In general a description "the equation gives X (in y)" tells you that the equation for X is formulated so that it comes out in units of y.
You can usually tell from the units in the body of the equation.
 

FAQ: Calculating the suns path in sky

How do you calculate the sun's path in the sky?

The sun's path in the sky can be calculated using basic trigonometry and knowledge of the earth's rotation. First, determine the latitude and longitude of your location. Then, use the current date and time to find the sun's declination (angular distance from the celestial equator). Finally, with these values, use the formula for calculating the sun's altitude (angle above the horizon) and azimuth (compass direction) at any given time.

What factors affect the sun's path in the sky?

The sun's path in the sky is affected by several factors, including the earth's tilt, the location and time of year, and the observer's latitude. The tilt of the earth's axis causes the sun's path to change throughout the year, resulting in longer days in the summer and shorter days in the winter. The observer's latitude also plays a role, as the sun's path will be higher in the sky at the equator compared to the poles.

How can I use the sun's path to determine the time of day?

The sun's path in the sky can be used as a natural clock to determine the time of day. By measuring the sun's altitude and azimuth, you can use the formula for solar time to calculate the time of day. This method is known as sundial time and was used before the invention of clocks.

Is there a difference in the sun's path in the sky between the northern and southern hemispheres?

Yes, there is a difference in the sun's path in the sky between the northern and southern hemispheres. This is due to the earth's tilt, which causes the sun's path to be higher in the sky in the northern hemisphere during the summer and higher in the southern hemisphere during the winter.

How does the sun's path in the sky change throughout the day?

The sun's path in the sky changes throughout the day due to the earth's rotation. The sun rises in the east and sets in the west, which means its path will move from east to west throughout the day. The sun's altitude will also change, reaching its highest point (known as solar noon) when it is directly overhead. The length of the sun's path will depend on the time of year and the observer's location.

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