Knowing the Weather – At twilight, the Earth’s shadow becomes visible on the horizon – Meteo

When the sky is clear, just before sunrise and right after sunset, you can see the Earth’s shadow as a dark arc on the horizon.

When the sun disappears below the horizon, it is worth looking to the other side. There, shortly after sunset, an exciting optical phenomenon appears: the arc of the Earth’s shadow. The sun’s rays no longer reach the lowest levels of the atmosphere, so the Earth’s shadow becomes visible as a dark band on the horizon. This stands out nicely from the orange-pink “belt of Venus” above, where the sun’s rays are still shining directly.

Legend:

When the sun disappears below the horizon towards the west, a dark band appears above the horizon towards the east. Just before sunrise, the arc of the Earth’s shadow to the west can be observed.

SRF Weather

As the sun sinks below the horizon, Venus’ belt fades and Earth’s shadow blends seamlessly into the dark night sky. By the way, the best way to observe the arc of the Earth’s shadow is from the top of a mountain or hill. On the one hand, the chances of being outside the layer of fog are greater there, and on the other hand, the horizon is lower and the Earth’s shadow becomes visible a little earlier.