Sunrises and sunsets on the compass

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In summary, the conversation is about the sun's movement in relation to the compass and how it differs depending on the season and latitude. The individual is asking for confirmation on their understanding of the sun's position at various times of the year. They are also referred to a website for more detailed information and tables on the sun's altitude, declination, and azimuth.
  • #1
DaveC426913
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I feel a fool for even asking this; my father is a Geography teacher, and I am supposedly well-educated in the sciences.

But the only dumb question is the one not asked, so...


I've never quite understood where the Sun actually rises and sets on the compass. It does not set due West (except at brief, specific times of the year).

If I live at 45N lat. then:
- at summer solstice, the sun rise to within ~22.5d of zenith at noon
- at summer dusk, the sun will not set due West, it will set at ~22.5d North of due west
- in the peak of winter, the sun will only rise to within 67.5d of zenith at noon
- at winter dusk, the sun will set 22.5d south of due west

Are these suppositions correct?
 
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  • #2
Hi,

Your values are approximately correct for the height at noon. I believe the formula is (L-delta) where L is the latitude and delta is the angular distance of the sun above (or below) the equator. On summer solstice the result is (45-23.5) or 21.5 degrees from zenith, while for winter solstice it is (45+23.5) or 68.5 from zenith.

However, these may not translate exactly into the north south deviations of the sun at sunrise and sunset. The equations may notbe linear in this manner. I am not sure. You can probably look them up on the web. They might be found by searching for solar altitude, declination, or azimuth.

Try this site for tables.

http://aa.usno.navy.mil/data/docs/AltAz.html [Broken]

juju
 
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  • #3



First of all, let me assure you that there is no shame in asking questions about things that you may not fully understand. As you said, the only dumb question is the one not asked. It is important to continue learning and seeking knowledge, no matter how much education or experience one may have.

To answer your question, yes, your suppositions are correct. The position of the sunrise and sunset on the compass is determined by the Earth's tilt on its axis and its rotation around the sun. As you mentioned, during the summer solstice, the sun rises and sets closer to the North (or South, depending on your location) than it does during the winter solstice.

This phenomenon is also responsible for the changing lengths of days throughout the year. During the summer solstice, the sun is at its highest point in the sky and therefore has the longest period of daylight. Conversely, during the winter solstice, the sun is at its lowest point and has the shortest period of daylight.

I hope this explanation helps to clarify your understanding of the sun's position on the compass. Remember, there is always more to learn and it is never too late to ask questions. Keep curious and keep seeking knowledge.
 

1. What causes the different colors in sunrises and sunsets?

The different colors in sunrises and sunsets are caused by the scattering of light by particles in the Earth's atmosphere. The shorter, bluer wavelengths of light are scattered more, leaving behind the longer, redder wavelengths which give the sky its vibrant colors.

2. Why do sunrises and sunsets appear at different locations on the compass?

The location of sunrises and sunsets on the compass is determined by the Earth's rotation on its axis. As the Earth rotates, different parts of the planet are facing towards or away from the sun, resulting in different locations for sunrises and sunsets.

3. Are sunrises and sunsets the same length of time?

No, sunrises and sunsets are not the same length of time. The length of a sunrise or sunset depends on the time of year and the latitude of the observer. In general, sunrises and sunsets are longer near the equator and shorter near the poles.

4. Can sunrises and sunsets be predicted?

Yes, sunrises and sunsets can be predicted using mathematical models and astronomical data. These predictions can be affected by factors such as weather conditions and the Earth's atmosphere, but they are generally accurate.

5. Do sunrises and sunsets look the same from all locations on Earth?

No, sunrises and sunsets can look different from different locations on Earth. Factors such as altitude, weather conditions, and atmospheric composition can affect the appearance of sunrises and sunsets. Additionally, the time of year and latitude of the observer can also impact the colors and duration of sunrises and sunsets.

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