If an object moving smoothly across the sky exhibits flashing lights, what might it be instead of a star?

Answer

An airplane with navigation lights.

If an object shows steady movement across the background stars, it is likely an artificial source like an airplane or satellite, rather than a distant star which remains fixed relative to other stars.

If an object moving smoothly across the sky exhibits flashing lights, what might it be instead of a star?

#Videos

What Does It Mean When A Star Is Flickering? - Physics Frontier

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