The Quantity Rule Of Animal Crossing Star Fragments

According to the introduction of the official strategy book, when making a wish to the meteor shower.

The number of fragments that can be obtained depends on the number of times the island owner makes a wish (up to 20) + the number of times the tourists make a wish (up to 100) * 0.2. 

Therefore, the maximum number of star fragments that can be picked up at one time is 40, so players can improve the efficiency of making a wish.