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Why do blue and green objects look brighter than red objects in very dim light?

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A circular RYB color wheel divided into twelve segments, showing a progression of colors from red, orange, and yellow to green, blue, and violet. — colour The RYB color model is being illustrated on a color wheel.

Blue and green objects appear brighter than red objects in dim light due to a phenomenon known as the Purkinje shift.21

This effect occurs because the human eye relies on two different types of photoreceptors: cones, which function in bright light, and rods, which are specialized for vision in low-light conditions (scotopia).234

In daylight, our vision is dominated by cones, which are most sensitive to yellow-green light (around 5550 angstroms). However, as light intensity decreases, the eye transitions to rod-mediated vision. Rods contain a visual pigment called rhodopsin, which is most sensitive to blue-green light (peaking near 5000 angstroms or 496 nm). As darkness increases, the rod luminosity scale prevails over that of the cones, causing red objects—which are less stimulating to rods—to appear much darker or black, while blue and green objects appear relatively brighter.25361