In and around totality — the brief moments during a total solar eclipse when the moon fully hides the sun — the sudden shift from light to darkness can profoundly change color perception.

As a solar eclipse approaches totality and our eyes adjust to dimming light, our color vision changes. It’s called the Purkinje effect.

During the total lunar eclipse early Friday morning, the moon will still be visible in the night sky, but its color will change. Here's when and how to see the Blood Moon.