1. find the closest E◉ in the Nautical Almanac that is prior to the observation time.

2. Since E◉ is given in even-numbered hours, if you want E◉ at an arbitrary time, you can simply calculate it by eye.

3. By adding the observation time (U.T.C.) to the E◉ obtained in step 2, the time angle can be easily obtained.

4.The obtained hour angle is in hours, so if you wish to obtain the angle in angles, you can do so by multiplying by 15.

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5. In the case of declination, find the closest declination before the observation time.

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For solar declination, find the P.P. value of declination from the P.P. value in the right column. At this time, If the declination are increasing, add them.

Find the midday time of January 1, 165°E

How to calculate the sun's midday time.

1. L.A.T. is a constant and must be 12h00m00s.

2. L.T. is a longitude-time and is the number of longitude divided by 15. It is also calculated by East + and West -.

3. What is obtained by this is G.A.T. Using this time, we obtain E◉ from the Nautical Almanac. 

4. E◉ is given in even-numbered hours, so if we want E◉ at an arbitrary time, we can simply calculate it by eye.

Subtract "E◉ - 12h00m00s" to get the Equation of Time.

6. By adding or subtracting G.A.T. and Equation of Time, G.M.T. can be calculated.(The sign of the Equation of Time is reversed.)

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7. L.M.T. can be calculated by adding or subtracting longitude time or standard time.

8.Approximate median time can also be obtained, which is indicated by the M.P. under the sun column. (in the blue frame of the sample image)

Sun's Altitude Correction

Find the hour angle and declination of January 1, 1:20 in U.T.C.