The Red Sky Paradox

 The Sun & Sky Should Be Red—But They Aren't

Perhaps you learned in elementary school that the sky is blue because the Sun is so bright. The Sun looks yellow or orange, depending on what particles its light passes through on its way to our eyes. Without all this "interference" near Earth's surface, we would see that the Sun's light is actually white. Oddly enough, white light is not what astronomers would expect of a star that is host to a life-bearing planet. Red light is, and for several reasons.

First, stars called "red dwarfs" (stars just hot enough to sustain nuclear burning) are the most numerous in the universe. They account for 78 percent of all nuclear-burning stars.¹ As slower nuclear burners, they continue to...