Ep. 21: Luna and others investigate ruins while Bell prepares a cave as winter approaches

21

Luna, Shingo, and Chako explore the ruins for shelter but fail to enter, returning with a substance sample. Meanwhile, Menori and Howard create cloaks from shuttle upholstery. Bell urges the group to move to a cave due to dropping temperatures, but the children resist leaving their home. Bell works alone on the cave for a week until Kaoru secretly shares fish with him. Luna discovers his progress, but Bell collapses from exhaustion. He shares a childhood story about his father preparing for a cold snap. Inspired, the others join him. Chako identifies the ruins' emission as an infrared reflector blocking solar heat, confirming the worsening weather. The cave is completed just as snow begins to fall.