The blood shadow of the Earth
There is long shadow dragging behind the Earth, and it normally sweeps over the darker space only, making it hard to detect its existence.
But occasionally, the Moon bravely breaks into this darkness, acting as a curtain. Only then can we get an opportunity to witness the shadow of the Earth while we are on the Earth itself.
Unfortunately, the curtain of Moon is not huge enough to show the complete picture of the Earth, which inspires the idea of putting photos of different stages of eclipse together, giving us a glimpse of this marvelous blood shadow of the Earth.