What is the primary test an observer can use to distinguish atmospheric scintillation from a true stellar change?

Answer

Observing the change in flashing intensity as the star's altitude changes

The primary test is altitude; if the flashing diminishes as the star drifts higher in the sky (where the light path is shortest), the cause is atmospheric.

What is the primary test an observer can use to distinguish atmospheric scintillation from a true stellar change?

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A Strange Blinking Star Is Troubling The Astronomers - YouTube

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