Approximately how small is the brightness dip caused by an Earth-sized planet orbiting a Sun-like star?

Answer

About 80 parts per million (0.008 percent).

For an Earth-sized planet orbiting a similar star, the brightness dip plunges to about $0.008$ percent, which is equivalent to about 80 parts per million.

Approximately how small is the brightness dip caused by an Earth-sized planet orbiting a Sun-like star?

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