Sunbeam

Sunbeam refers to a beam of sunlight, typically the visible column of light that appears when sunlight streams through gaps in clouds, fog, or dust. In ordinary daylight the Sun is often not directly visible, and its rays become visible only after they are scattered by atmospheric particles such as dust, water droplets, or haze. The phenomenon arises from scattering and, to a lesser extent, diffraction; the beam itself is a narrow, roughly straight path of light that appears brighter due to a higher concentration of photons within that path.

Crepuscular rays are a common form of sunbeam seen at dawn or dusk when sunlight is cast through breaks in the cloud layer, producing parallel-looking shafts that diverge due to perspective. Anticrepuscular rays are similar shafts visible opposite the Sun. In clear air, sunbeams are rarely seen unless the light is foreshortened by particles, so their presence often signals local aerosols or mist.

In photography and film, sunbeams are often highlighted for dramatic effect; their color can range from white to warm or cool tints depending on spectral composition and atmospheric conditions. The term is usually synonymous with sunray and can also be described as god rays in popular usage.

The concept is distinct from solar beams studied in physics and engineering, such as laser beams or solar energetic particle streams, though all share the common feature of directed light or radiation.