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Real astronomy and dated history, with sources. Documented traditions and folklore. Modern lunar astrology · symbolic, not predictive.

Fact #148 Observing

Stand in exactly the right place — a track a few hundred metres wide — and a star will flick on and off several times as it grazes the mountains and valleys of the Moon's limb.

It is the sharpest way to measure the profile of the lunar edge, which matters because the same profile decides exactly where a solar eclipse is total. Amateur observers strung out along a road contributed most of the data that built those limb profiles, and the results still feed into eclipse predictions.

Source: International Occultation Timing Association; Watts limb charts · checked Sep 2026

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Stand in exactly the right place — a track a few hundred metres wide — and a star will flick on and off several times as it grazes the mountains and valleys of the Moon's limb.

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Stand in exactly the right place — a track a few hundred metres wide — and a star will flick on and off several times as it grazes the mountains and valleys of the Moon's limb.

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