Ключевые слова: alternative, astronomy, astrophysics, atmosphere, celestial sphere, clean energy, climate, clouds, combustion, ecofriendly energy, ecological, ecology, electricity, energy, heat, holidays, hydrogen, infrared, ionosphere, life, light, particles, photovoltaics, planets, rays of the sun, renewable energy, sky, solar mass, solar power, solar radiation, star, sun, sun rays, sunlight, tan, the sun god, uva rays,