What causes the Starlink satellites to become suddenly invisible during a pass?

Answer

They pass over the terminator line and enter the Earth's shadow

As the Earth rotates, the satellites move into the region where the Earth blocks the sun's illumination, causing them to abruptly disappear from view.

What causes the Starlink satellites to become suddenly invisible during a pass?

#Videos

Starlink satellites, the string of lights in the night sky. - YouTube

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