On June 21, what is the noon sun angle at 74 degree south Latitude?

Question

since it's not possible to have a negative answer, explain the situation above.

Answer 1

Noon Sun Angle - Sample Calculation (Northern Hemisphere)

At noon, the sun is in the south and reaches its highest point in the sky. We can measure how high in terms of the angle of the sun above the horizon. The noon sun angle changes throughout the year due to the 23.5 degree tilt of the earth's axis. The sun is at its highest on the first day of summer and lowest on the first day of winter.

The noon sun angle also depends on latitude. Latitude lines run from 0 degrees at the equator to 90 degrees at the poles. The higher the latitude, the lower the angle of the sun above the horizon.

Consider a location in Florida at 30 degrees latitude. The noon sun angle on the first days of spring and fall (when there is no tilt toward or away from the sun) is 60 degrees. To determine this angle, subtract the latitude from 90, i.e. 90 - 30 = 60 degrees.

On the first day of summer when the earth's axis is tilted 23.5 degrees TOWARD the sun, the noon sun angle is 60 + 23.5 = 83.5 degrees. On the first day of winter when the axis is tilted 23.5 degrees AWAY from the sun, the noon sun angle is 60 - 23.5 = 36.5 degrees.

You can see how significant the change in the noon sun angle is from winter to summer. When the sun is higher in the sky, the sun's rays are more direct (more overhead) which means they will be more intense. This is one of the reasons why it is warmer in the summer than in the winter.

Practice Calculation
A place is located at 50 degrees latitude. Determine the noon sun angle on the first days of:
a. spring
b. summer
c. fall
d. winter

(answers: a. 40 b.63.5 c. 40 d. 16.5)



A nautical almanac is a publication describing the positions and movements of celestial bodies, including the sun, moon, planets, and 57 stars chosen for their ease of identification and wide spacing. The Almanac specifies for each whole hour of the year the position on the Earth's surface at which each body is directly overhead. The Sun, Moon and Planets 'move' independently and so are specified separately, but for the stars only Aries is specified, the other stars having a set angular distance from that. The navigator can extrapolate by means of difference tables to obtain the position of each object for each minute of time.

In Great Britain a nautical almanac has been published annually by the HM Nautical Almanac Office, ever since the first edition was published in 1767.

To find the position of a ship or aircraft by celestial navigation, the navigator uses a sextant to take a 'sight' to measure the apparent height of the object above the horizon, and notes the time from a chronometer. The object's position is then looked up in the Nautical Almanac for that particular time and after allowance for refraction, instrument error and other errors, a position circle on the Earth's surface is calculated.

If you go to the second link you can calculate this but you need the longitude to get an answer.

Answer 2

This link will help

http://www.phy6.org/stargaze/Slatlong.htm