https://apod.nasa.gov/apod/ap240228.html

                    Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our
  fascinating universe is featured, along with a brief explanation
                written by a professional astronomer.

                          2024 February 28
 A rocky shoreline is shown with land on the right and water on the
       left. Above is a sky that shows unusually pixelated and
 coloredvertical bands. Please see the explanation for more detailed
                            information.
                           Shades of Night
             Image Credit & Copyright: Dario Giannobile

Explanation: How does the sky turn dark at night? In stages, and with
different characteristic colors rising from the horizon. The featured
image shows, left to right, increasingly late twilight times after
sunset in 20 different vertical bands. The picture was taken last
month in Syracuse, Sicily, Italy, in the direction opposite the Sun.
On the far left is the pre-sunset upper sky. Toward the right,
prominent bands include the Belt of Venus, the Blue Band, the Horizon
Band, and the Red Band. As the dark shadow of the Earth rises, the
colors in these bands are caused by direct sunlight reflecting from
air and aerosols in the Earth's atmosphere, multiple reflections
sometimes involving a reddened sunset, and refraction. In practice,
these bands can be diffuse and hard to discern, and their colors can
depend on colors near the setting Sun. Finally, the Sun completely
sets and the sky becomes dark. Don't despair -- the whole thing will
happen in reverse when the Sun rises again in the morning.

                 Tomorrow's picture: extra February

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