The Cause of the Seasons
Motivation
Some seasons are good for planting crops while some are not. Some seasons are good for fishing while others are not. Some seasons are good for hunting animals while others are not. If we can understand what causes the seasons, we can better prepare for them, harvesting more food to ensure our survival and help us flourish. The Sun's light warms things up. In addition, the Sun travels different lengths of path across the sky during the day, sometimes making the day longers, sometimes shorter.
Question
Since the Sun warms the Earth, and Sun is up for different durations of time on different days, does the amount of time for which the Sun shines on the Earth cause the seasons?
Investigation
An ancient astronomer records:
- Daily warmth according to what he feels directly
- Time that the Sun is in the sky
- Highest angle that the Sun makes with the horizon in a given day
This astronomer observes that the longest day is also the day when the Sun reaches its highest point in the sky and that the hottest days tend to occur about 60 days after the longest day. Similarly, the shortest days is also the day when the Sun reachest the lowest high point in the sky, and the coldest days tend to occur about 60 days after the shortest day. Although the delay from the longest day to the hottest day, it can be understood since objects take time to heat up and cool down.
Conclusion
The amount of time for which the Sun shines on the Earth casues the seasons
Comments
Recording time requires a time-recording device such as a water clock or a shadow clock and a conceptual unit for measuring time (presumably, the hour). Given the worldwide diversity of prehistoric sites with solar alignments, it seems likely that measuring sunrise and sunset points on the horizon and tracking their variation over the course of the year conceptually precedes measuring the temporal length of the day.
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