👉 In physics and astronomy, a penumbra is an area of light that appears to be brighter than surrounding areas due to the angle between the sun's rays and the observer's line of sight. This phenomenon can occur when the angle of incidence from a solar eclipse is greater than 90 degrees (the maximum angle at which sunlight can reach Earth), causing the light to travel through an opaque medium, such as water or air. The term "penumbral" comes from the Greek word "
