Not sure about that David. Eye has quite a large airy disc. This is maximum permissible exposure of a laser beam, a point source. Solar constant at Earths surface is about 100mW per square centimetre. Even factoring in that sun is not a point source viewing it naked eye is certainly hazardous. If supernova Betelgeuse was as bright as full moon then it would be 340,000x less.
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