A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

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Absolute Brightness (Absolute Magnitude):

A measure of the true intensity of an object. The absolute intensity or magnitude of an object is the apparent intensity or magnitude it will have if it were situated exactly 32.6 light-years (10 parsecs) away.

Absolute Zero:

The coldest probable temperature, at which all molecular motion stops. On the Kelvin hotness scale, this temperature is the zero point (0 K) that is equivalent to –273° C and –460° F.

Absorption:

The procedure by which light transfers its power to matter. For example, a gas cloud could absorb starlight that passes through it. After the starlight passes during the cloud, dark lines called amalgamation lines appear in the star’s continuous spectrum at wavelengths equivalent to the light-absorbing elements.

Active Galaxy:

A galaxy possessing a lively galactic nucleus at its center.

Atom:

The smallest unit of substance that possesses chemical properties. All atoms have the similar basic structure: a nucleus containing absolutely charged protons with an equivalent number of pessimistically charged electrons orbiting around it.