Myths: Light & color

Light & color

1. Visible light is the only type of light.

Visible light is just a tiny slice of radiation that makes up the electromagnetic spectrum. In order from lowest energy to highest energy, and longest wavelength to shortest wavelength, the radiation types are: radio, microwave, infrared, visible light, ultraviolet, X-rays, and gamma rays.

2. All radiation is harmful.

All radiation is not harmful. Light is a form of radiation. All parts of the electromagnetic spectrum are considered radiation, but only X-rays and gamma rays are made up of harmful, ionizing radiation. Ionizing radiation is dangerous because it can penetrate body tissues and cause cell damage. Ultraviolet light from the Sun causes sunburn, which is a common form of “harmful” radiation. Radiation with wavelengths equal to or longer than visible light (radio, infrared, and visible light) is considered harmless.

3. The primary colors of light are identical to the primary colors of pigments.

The primary colors of light are red, green, and blue, while the primary colors of pigments are red, yellow, and blue. When combined, the primary colors of pigments produce a black pigment, while the primary colors of light produce white light.

4. Red objects in space are hot; blue objects are cool.

In astronomy, the color of an object does not always signify its temperature. An object's color can mean many different things, including its distance from Earth, its temperature, and its chemical makeup.

5. Filters change the color of light.

Filters don't change the color of light, but they do allow only certain colors of light to pass through, and block the others.

Myths: Light & color