The Earth Shadow and the Belt of Venus

When the sun sets, people usually just look at and appreciate the setting sun without looking at the opposite side of the sky to see another phenomenon. When sunset skies are almost cloudless, you should be able to see the Earth's shadow opposite the sunset. It's best to spot this right after the sun has slipped down the horizon.

So, if you look at the eastern part of the sky, you'll see a dark bluish gray narrow band hanging above the eastern horizon. When you spot that, you're actually seeing the shadow of the Earth cast upon the atmosphere. It's a narrow band that quickly disappears as the twilight gives way to the darkness of the night.

Hanging above the Earth shadow (or Earth's shadow) is the so-called Belt of Venus, which you can identify by its orangey or pinkish hue. I don't know why they call it that way. The Earth shadow fades into the Belt of Venus, which in turn fades into the blue sky.