The sky on Mars isn't actually pink. It's more of a pale butterscotch yellow during the day, and a reddish-brown at sunset and sunrise.

Here's why:

* Dust: Mars has a very dusty atmosphere, filled with fine particles of iron oxide (rust). This dust scatters sunlight, giving the sky its yellowish hue.

* Wavelengths: Blue light is scattered more easily than red light by the dust particles. This is similar to why the Earth's sky is blue – blue light is scattered more by the atmosphere. However, on Mars, the dust absorbs the blue light, leaving more yellow and red light to reach our eyes.

* Sunrise/Sunset: At sunrise and sunset, the sunlight travels through more of the atmosphere. This causes even more blue light to be scattered away, resulting in the reddish-brown color we see.

So, while the sky on Mars might look pink in some photographs due to color adjustments, it's actually more of a yellowish hue during the day and a reddish-brown at sunrise and sunset.