Angular distance
Angular distance is the angle between the rainbow axis and the direction in which an observer must look to see a specific colour within the arcs of a rainbow. Angular ...
Angular distance
When discussing rainbows, angular distance is the angle between the line from the observer to the centre of the rainbow (rainbow axis) and the line from the observer to a ...
Angular distance
When discussing rainbows, angular distance is the angle between the line from the observer to the centre of the rainbow (rainbow axis) and the line from the observer to a ...
Anti-solar point
On a sunny day, stand with the Sun on your back and look at the ground, the shadow of your head coincides with the antisolar point. The anti-solar point is ...
Areas around rainbows
The area inside a primary rainbow The area inside the arcs of a primary rainbow, from its centre-point out to the violet band at 40.70 appears tonally lighter or brighter ...
Artificial light source
An artificial light source is any source of light created by humans, as opposed to natural light sources like the sun or stars. Artificial light sources are generated by converting ...
Atmospheric rainbow
An atmospheric rainbow is an arc or circle of spectral colours and appears in the sky when an observer is in the presence of strong sunshine and rain. Atmospheric rainbows: ...
Atmospheric rainbows summary
Rainbows form when sunlight encounters a curtain of rain. The sunlight enters raindrops at one angle and then emerges at another. The water droplets have to be in just the ...
Atom
An atom is the smallest unit of a chemical element that retains all of its physical and chemical properties. At the core of an atom is a nucleus that contains ...
Atom
An atom is the smallest unit of a chemical element that retains all of its physical and chemical properties. At the core of an atom is a nucleus that contains ...
Atom as a light source
An atom isn't typically considered a light source in the conventional sense because it can't generate light spontaneously. In its "ground state," an atom is stable and doesn't emit light ...
Attributes of visual perception
Attributes of visual perception consist of inherent abilities and skills developed over time that facilitate our understanding of visual information.Attributes of visual perception associated with the response of the human ...
Aurora
Aurora (also known as the polar lights) are natural displays featuring curtains, rays, spirals, and flickering patterns of light in the northern polar latitudes (Aurora Borealis) and southern polar latitudes ...
Aurora
Auroras are caused by the interaction between charged particles (such as electrons), ejected from the Sun (solar wind), with the Earth's magnetosphere. The magnetosphere accelerates electrons as they enter the ...
Bands of colour
An observer perceives bands of colour when visible light separates into its component wavelengths and the human eye distinguishes between different colours. In the presence of a rainbow, an observer ...
Bands of colour
An observer perceives bands of colour when visible light separates into its component wavelengths and the human eye distinguishes between different colours. The human eye and brain together translate light ...
Bands of colour
The fact that we see a few distinct bands of colour in a rainbow, rather than a smooth and continuous gradient of hues, is sometimes described as an artefact of ...
Bands of colour, spectral and non-spectral colours
About bands of colour, spectral and non-spectral colours Bands of colour Bands of colour are composed of a continuous range of wavelengths, so for example: A continuous range of wavelengths ...
Bioelectroluminescence
Bioelectroluminescence is a type of chemiluminescence where the emission of light is specifically produced by a biological process within a living organism. Bioelectroluminescence is a type of chemiluminescence where the ...
Bioluminescence
Bioluminescence is a type of luminescence resulting from the production and emission of electromagnetic radiation by living organisms. Bioluminescence, meaning "living light," occurs in a wide variety of creatures, from ...
