The Winter Solstice, in the southern hemisphere, occurs on or very close to the 21st of June each year. It is part of the yearly cycle as the Earth orbits around the Sun and was one of the four times of the year closely observed by people such as those who lived in what we now call Egypt many thousands of years ago. The diagram below shows the position of the Earth with sunlight shining from the right of the image, and how the number of daylight hours is effected depending on where you are. Australia has the Tropic of Capricorn running across the country just south of Rockhampton in Queensland. Ancient people in Egypt paid great attention to cycles and little or no attention to time - perhaps we could learn something from that. They were masters of understanding how the Earth moved around the Sun, when the Equinox's and Solstice's occurred, how the stars moved in the sky at night and how their positions changed over time. They understood and observed the constellations and what they represented. It is clear they understood what is known as 'precession' which is caused by the slow wobble in the Earth's axis and represents a cycle of approximately 25772 years (different sources quote slightly different figures). I'll write another blog about precession another time. The Winter Solstice in the Southern Hemisphere marks the day with the least number of daylight hours, and the most hours of darkness. The further south you are located the smaller the number of daylight hours becomes. The Winter Solstice marks the day when the sun rises in its most north-easterly position, and sets in its most north-westerly position. The sun is also at its lowest point at midday as the diagram below hopefully indicates. Interestingly, the Winter Solstice with it's smallest number of daylight hours, does not mark the middle of Winter or the coldest days of the year. This occurs during the following month and is probably the subject of another blog.
The last thing to note regarding the Winter Solstice and the Summer Solstice in six months time, is that by observing the position of the sun rise on the horizon on both occasions, and dividing the angle between these two positions in half gives you exactly due East.
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AuthorI love to understand things, how they work, why they happen - I'm always learning and keen to investigate... Archives
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