We all know that moon phases are caused by the shadow of the Earth falling on the moon. I think I read somewhere that the shadow of the earth travels about 1 million kilometres. Have you ever wondered what the speed of shadow is?
Anyway there is an easier more spectacular way of viewing the Earth’s shadow. Just look west during sunrise and east during sunset. I’m positive most of us have seen this and either dismissed it as a clump of clouds or just darkness creeping in. But it’s pretty cool when you realise that it’s actually Earth’s shadow that’s beginning its long journey.
The shadow of the Earth is that dark blue band and the pink band above it is called the belt of Venus (essentially refracted light).
If you look west during sunrise you can once again observe the shadow.