Illustration of an astronaut exploring a lush, alien world with vibrant foliage and towering trees, set against a backdrop of distant mountains under a swirling nebula sky. The scene captures a masterpiece of sci-fi atmosphere with intricate, highly detailed elements in sharp focus. The astronaut's suit reflects the verdant surroundings, dotted with otherworldly fauna. Streams of light break through the canopy, casting dappled shadows on the forest floor. This 4k resolution piece is trending on artstation, showcasing the beauty and mystery of the cosmos.