Peel and section oranges over a bowl, reserving any juice. Stir together orange sections, juice, pineapple, and coconut. Cover and chill 8 hours.
Beat whipping cream until foamy; gradually add powdered sugar, beating until soft peaks form.
Spoon fruit mixture into individual dishes; top each serving with whipped cream and a cherry.
Note: For sweeter ambrosia, stir 2 tablespoons granulated sugar into fruit mixture.
