Optical phenomenon

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An optical phenomenon is any observable event which results from the interaction of light and matter. See also list of optical topics and optics.

Common optical phenomena are often due to the interaction of light from the sun or moon with the atmosphere, clouds, water, or dust and other particulates. One common example would be the rainbow, when light from the sun is reflected off water droplets in rain as it falls to the ground. Others, such as the green flash, are rare due to atmospheric conditions. Some, such as instances of Fata morgana, are commonplace only in certain locations.

Other phenomena are simply interesting aspects of optics, or optical effects. The colors generated by a prism are often shown in classrooms for instance.

SunHaloOverGoldenBay4thFeb06 — Sun Halo at latitude 41 degrees South

A list of optical phenomena[]

Entopic phenomena include optical phenomena arising from the structures of the eye.

Some optical illusions can be explained as observations of unusual optical phenomena.

Atmospheric optical phenomena[]

Afterglow
Airglow
Alexander's band, the dark region between the two bows of a double rainbow.
Alpenglow
anticrepuscular rays
Auroral light (northern and southern lights, aurora borealis and aurora australis)
Belt of Venus
crepuscular rays
Elves [1]
Glories (also known as Brocken's Specter or Specter of the Brocken)
the Green ray
Halos, of Sun or Moon, including sun dogs
Heiligenschein or halo effect, partly caused by the Opposition effect
Rainbows
Mirages (including Fata Morgana)
Sprites [2]

PaulMossSunHalo19Jan2006PICT2800web — Sun Halo

Shadow set

Other optical phenomena[]

Gegenschein
Iridescence
Opposition effect
Sylvanshine
Zodiacal light

Optical effects[]

Asterism, star gems such as star sapphire or star ruby.
Aura, a phenomenon in which gas or dust surrounding an object luminesces or reflects light from the object.
Aventurescence, also called the Schiller effect, spangled gems such as aventurine quartz and sunstone.
The camera obscura
Caustics
Chatoyancy, cat's eye gems such as chrysoberyl cat's eye or aquamarine cat's eye
Chromatic polarization
Cathodoluminescence
Diffraction, the apparent bending and spreading of light waves when they meet an obstruction.
Dispersion
Double refraction
The Double-slit experiment
Electroluminescence
Fluorescence, also called luminescence or photoluminescence.
Phosphorescence
metamerism as of alexandrite
Newton's rings
Pleochroism gems or crystals which seem many-colored
Rayleigh scattering (Why the sky is blue, sunsets are red, clouds are white, and associated phenomena)
Sonoluminescence
- Shrimpoluminescence
Synchrotron radiation
The separation of light into colors by a prism
Triboluminescence
The Zeeman effect
Thomson Scattering
Total internal reflection
The Umov effect
Polarized light-related phenomena such as double refraction, or Haidinger's brush
The ability of light to travel through space or through a vacuum.

Entoptic phenomena[]

Main article: Entoptic phenomenon

Diffraction of light through the eye lashes
Floaters
Haidinger's brush
Monocular diplopia (or polyplopia) from reflections at boundaries between the various ocular media
Phosphenes from stimulation other than by light (e.g., mechanical, electrical) of the rod cells and cones of the eye or of other neurons of the visual system
Purkinje images.

Optical illusions[]

Main article: optical illusion

The unusually large size and rich color of the Moon as it rises and sets

There are many phenomena which result from either the particle or the wave nature of light. Some are quite subtle and observable only by precise measurement using scientific instruments. One famous observation was of the bending of light from a star by the Sun during a solar eclipse. This demonstrated that space is curved. See Theory of relativity.

Observations of some phenomena such as the photoelectric effect, the flow of electric current in a material or through a vacuum (as in a photocell) when the material is exposed to light, led to advances in science, as they could not be easily explained by existing theory.

Unexplained phenomena[]

Some phenomena are still unexplained, and they could very possibly be some kind of optical phenomena. Some consider many of these "mysteries" to be simply local tourist attractions not worthy of investigation. [3]

Marfa lights [4]
Hessdalen lights [5]
Min Min lights [6]
Earthquake lights [7]
Light of Saratoga [8]

External links[]

Atmospheric Optics Reference site
SpaceW Site for reporting Aurora activity data
Spaceweather.com Official NASA site with many photos
Astronomy in New Zealand Many atmospheric optical effect photos and descriptions