Sun Rise Calculations

Knowing the earth rotation and revolution correctly makes it possible to calculate the time and angle of sunrise precisely for any location on Earth.

We should be aware that there are areas near the poles where the sun remains visible or invisible the whole day.

We can calculate sunrise from longitude and equation of time.

the following equation will do the work

sunrise time = (720 – 4 x longitude – equation of time + time zone * 60) – hour angle x 4

Hour angle can be calculated from sun declination and location latitude. we will come back to it some other time.

You can find how equation of time is calculated in a previous post

This web app can give us the time and angle of sunrise for any place on earth. The app is a part of our android app SunCalc

Sun Rise/Set Angle















Sun Rise

Created With Apache echarts

Source : SunCalc App on google Play

to get the whole app for your android system go to google play and download it.

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