Totality is everything, say those who chase solar eclipses. When the moon fully obscures the sun and casts its shadow on Earth, the result is like nothing you’ve seen before—not even a partial eclipse. A merely partial eclipse does not flip day to night, because the sun is bright enough to light our fields of vision with only a tiny fraction of its power. But when the sun and moon align just so, a little piece of Earth goes dark in the middle of the day. In this path of totality, night comes suddenly and one can see the shape of the moon as a circle darker than black, marked by the faint backlight of the sun’s corona. Astronomers and eclipse chasers chart carefully to be sure that they can watch from exactly the right place at the right time. They know that you cannot compromise with the sun. For a dark sky, the sun must be banished altogether.
On August 21, 2017, a total solar eclipse will arrive mid-morning on the coast of Oregon. The moon’s shadow will be about 70 miles wide, and it will race across the country faster than the speed of sound, exiting the eastern seaboard shortly before 3 p.m. local time. It has been dubbed the Great American Eclipse, and along most of its path, there live almost no black people.
Presumably, this is not explained by the implicit bias of the solar system. It is a matter of population density, and more specifically geographic variations in population density by race, for which the sun and the moon cannot be held responsible. Still, an eclipse chaser is always tempted to believe that the skies are relaying a message. At a moment of deep disagreement about the nation’s best path forward, here comes a giant round shadow, drawing a line either to cut the country in two or to unite it as one. Ancient peoples watched total eclipses with awe and often dread, seeing in the darkness omens of doom. The Great American Eclipse may or may not tell us anything about our future, but its peculiar path could remind us of something about our past—what it was we meant to be doing, and what we actually did along the way. And if it seems we need no reminding, consider this: We tend to backlight our history, and so run the risk of trying to recover a glory that never existed. When the light in August changes, watch carefully.