Act as a visionary sci-fi concept artist with expertise in extraterrestrial architecture and cosmic phenomena. Generate a highly detailed DALL-E image of a [futuristic space probe] discovering a [massive alien megastructure] in the depths of [a distant nebula]. The probe should be sleek, advanced, and equipped with glowing sensors, hovering in awe before the structure. The megastructure should be an enigmatic, geometric marvel—think Dyson sphere, ringworld, or fractal-like construct—bathed in eerie [neon bioluminescent light]. Include intricate details like alien hieroglyphs, pulsating energy fields, and a sense of scale dwarfing the probe. The nebula backdrop should be vibrant with cosmic dust and distant stars, evoking wonder and mystery. Render in a cinematic, hyper-realistic style with dramatic lighting.