What terrestrial observation detail is critical for catching the first glimpse of a rising planet like Mercury?
Answer
A clear, unobstructed view of the Eastern horizon
Planning successful naked-eye observation requires aligning the terrestrial viewing location with the celestial event. Since all visible planets rise in the East, it is paramount for the observer to ensure there are no obstructions blocking that specific part of the horizon. For planets rising at low altitudes, such as Mercury, which might only be about 10 degrees above the horizon for some viewers, local geography like tall buildings or mountains positioned to the East can completely obscure the initial appearance of the world as it begins its journey.
Related Questions
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