Sun and Moon

Sun and Moon ("Munraito") is a logic puzzle invented by Naoki Inaba (Japan). A square grid contains planets in some cells. The goal is to place exactly one star and one stardust cloud into each row and each column of the grid. If a particular semicircle of a planet is illuminated, there must be a star in that rank to light it. A star shines horizontally and vertically only; planets and stardust clouds block starlight.

Sun and Moon

Cross+A can solve puzzles from 4 x 4 to 20 x 20.