Totality

Totality of a lunar eclipse, as witnessed in Sidney, Australia, by way of fizzenergy.com, a sample of Photography that is Out of This World. "The moon gradually glides into the Earth’s shadow, until the normally pale white colour disappears and is replaced by an orange and red hue," accurately enough, though this fails to mention the intervening stage. Because before the blood-red appears at totality, the curve of Earth casts the darkest evidence of our home planet's curvature, and the relatively enormous distance to the Sun, can be deduced, also, when only a few simple facts are already known. The blood red of totality, "is caused by sunlight being refracted around the edge of the Earth, through the atmosphere. Blue light from the sun tends to be scattered by the atmosphere so the light that reaches the surface of the moon during a lunar eclipse is predominantly red."