Design an engaging cover for a children's composition notebook with an exciting space and astronauts theme. Incorporate playful and childish designs such as cartoon-style planets, stars, rockets, and smiling astronauts. Utilize bright and vibrant colors to capture children's attention and spark their imagination. Integrate 2D drawings of whimsical space scenes, featuring astronauts exploring alien planets or floating in zero gravity. Include stickers of cute space creatures like aliens or friendly robots to add an interactive element to the cover. Ensure the overall design is fun, cheerful, and visually appealing to children. The cover should inspire creativity and make the notebook irresistible for young space enthusiasts. --ar 2:3 --v 6 --stylize 600