Ключевые слова: astronomy, atmosphere, balanced, blue, care, celestial, clean, climate, cloud, concept, connect, conservation, continent, cooperation, cosmos, development, earth, eco, ecology, ecosystem, education, environment, environmental, galaxy, geography, global, globe, grass, green, growth, hope, idea, leaf, map, nature, planet, planetary, plant, protect, protection, recycle, save, science, space, sphere, sustainability, universe, water, world,