Final answer:
Arthur Eddington proposed that the Sun's energy comes from hydrogen converting into helium through nuclear fusion, a process that takes place in the Sun's core where temperatures are the highest and which accounts for the Sun's energy output.
Step-by-step explanation:
True, Arthur Eddington is credited with suggesting that the Sun produces its energy by converting hydrogen into helium, a process now known to be nuclear fusion. This concept was further supported by research and theoretical work carried out by other scientists. In the core of the Sun, hydrogen nuclei (¹H) fuse to form helium nuclei (4He). This fusion happens primarily at the boundary of the helium core, where the temperature is highest and sufficient hydrogen is present. About 600 million tons of hydrogen are converted to helium every second to account for the Sun's energy output. A small percentage of the mass of the hydrogen is converted into energy in accordance with Einstein's famous equation, E=mc², leading to the prodigious energy output we observe from the Sun.