The sun's hot inner layers produce a fairly continuous spectrum of radiation, from infra-red to X-rays. When this radiation passes through the cooler outer layers, which are majorly composed of hydrogen ( ∼91.2% of all atoms is hydrogen), some wavelengths get absorbed. Ignoring the other elements composing the outer layers and considering only hydrogen, can you guess the longest missing wavelength in the rainbows we see on Earth?
What are fine black particles, chiefly composed of carbon, produced by incomplete combustion of coal, oil, wood, or other fuels called?