For a satellite train to be visible to the naked eye, what geometric condition must be met regarding the sun?

Answer

Satellites must catch the sun's rays while the observer is in darkness

Visibility occurs when the observer on the ground is in darkness (night or twilight) but the satellites are still high enough to catch the sun's rays.

For a satellite train to be visible to the naked eye, what geometric condition must be met regarding the sun?

#Videos

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

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