The Ratio Given in Isaiah 30:26

The other day, I noted Isaiah 30:26, which stated:

Moreover the light of the moon shall be as the light of the sun, and the light of the sun shall be sevenfold, as the light of seven days, in the day that the Lord bindeth up the breach of his people, and healeth the stroke of their wound.

According to this article, depending on the phase of the Moon, it reflects between 3 and 12% of the Sun's light, or an albedo of 0.12. "However the CERES Earth orbiting satellite climate radiometers have measured the value to be higher and somewhere between 0.136 and 0.137, at a lunar phase angle of seven degrees." In any event, if the Sun were 7 times as bright, per Isaiah, that would mean that the Moon would appear to have a brightness of between 84% and 95.2% of the normal Sun, making the ratio given by Isaiah fairly accurate.