Show an American Astronaut in a space suit planting genetically engineered plants on Mars.

With no water to nourish them, the plants were engineered to thrive on the solar radiation that is in the regolith. As a side effect, the genetics in the plants break down the light spectrum, producing the mix of colors. The roots of these plants will eventually soak up harmful elements in the regolith, allowing it to be harvested, taken inside the lava tube colony, and used to grow Earth crops. The plants can be reused to decontaminate more soil.