If I asked you "what color is the sky on Earth?" how would you answer?

Here's a swatch made from various pictures of the sky on Earth during one of my vacations:

The color of the sky on Earth varies greatly, depending on things like the angle of the sun, the temperature, altitude, and dust levels in the sky. Mars isn't much different in that regard.

Getting a true color image of the Martian sky, as it would appear to an astronaut standing on its soil, is a lot tougher than it sounds. Lander/rover cameras are primarily intended to collect information of value to scientists. They usually are greyscale. They take several images using different filters to represent the brightness of various wavelengths. From these we construct color images. Even putting a color scale in the image to assist with calibration isn't easy, because ambient light would affect the appearance of that color scale.

Dust in the Martian sky can alter the color towards salmon, brown, or butterscotch. Ice crystals in the Martian sky can alter the color towards violet. water on the dust gives the sky a pinkish hue. If ice and dust are low, the area of the sky near the sun can appear quite blue.

Here's another swatch. I made this one from a selection of pictures of the sky on Mars that are considered true color.

So if someone asks you what color the sky on Mars is, just point at any of those eight blocks and you'll be right.