According to IAU educational recommendations for visual charting, approximately how long should one track a sunspot to clearly observe the Sun's rotation?
Answer
Approximately two weeks.
The International Astronomical Union (IAU) frequently uses the sunspot tracking method as a primary educational example for demonstrating solar rotation. For the process of positional tracking to yield clear, convincing evidence of the rotation, the recommended duration for observing a specific sunspot’s path across the solar disk is stated to be approximately two weeks. This timeframe allows the observer to plot the movement relative to the edges of the visible solar surface sufficiently to determine the approximate rotational period.
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