What color is the Martian sky during sunset?

The Martian sky appears blue around the Sun during sunset. This is the opposite of the familiar orange and red sunsets seen on Earth.

Mars has a very thin atmosphere filled with fine dust particles, many containing iron-bearing minerals. During the day, that dust gives the sky a butterscotch, pink, or rusty appearance. Near sunset, sunlight travels through a longer path of dusty atmosphere, changing which wavelengths reach an observer.

The dust preferentially scatters blue light forward, keeping a blue glow close to the setting Sun while red and orange light spreads more widely across the surrounding sky. NASA rovers, including Spirit, Curiosity, and Perseverance, have photographed this effect from the Martian surface.

A common mix-up is saying that the entire Martian sky turns deep blue. The blue is most prominent near the Sun; the broader sunset sky can still look hazy, pink, gray, or reddish depending on dust conditions.