In advance, make stars. Tint fondant yellow and use small and medium star Cut-Outs? to cut 11 medium stars and 22 small stars. Brush with water and sprinkle with yellow Cake Sparkles?; let dry.

Bake and cool 23 cupcakes; 11 in white baking cups, 12 in silver foil baking cups. Ice bottom of 12 marshmallows and position on top of cupcakes with foil baking cups.

Cover marshmallows with tip 12 vertical lines to fill in top; round and smooth with spatula and flatten with finger dipped in cornstarch.

Pipe tip 2A gray ring around iced marshmallow. Use spatula to ice remaining top of cupcake and smooth to a beveled edge. Position mini candy-coated chocolates.

Pipe tip 6 Martian face and pull-out ears (smooth with finger dipped in corn starch). Pipe tip 1 dot eyes and outline mouth.

Cut 1/2 in. off end of lollipop stick and insert into cupcake top; attach candy-coated chocolate on top.

Ice cupcakes in white baking cups with chocolate icing; position 1 medium and 2 small fondant stars on each cupcake.

Position all cupcakes on stand.