Paint the small balls to resemble planets, adding simple color variations, then let them dry fully.
Cut layered cloud shapes and a crescent sun from cardstock, then glue them inside the shadow box background.
Use a paint pen or brush to add scattered white dots for stars across the backdrop.
Thread fishing line through each planet, adjusting string lengths to create varied hanging depths.
Secure the strings to the top inside edge of the frame, spacing planets evenly so they appear to float.