A galaxy that emits large amounts of energy from its centre as electromagnetic radiation. The source of the energy output is believed to result from matter falling onto a supermassive black hole at its centre.

Supergiant elliptical galaxy M87 in Virgo is an active galaxy.

Messier 87 is an active galaxy (credit:- NASA, ESA, and The Hubble Heritage Team (STScI/AURA))

Glossary 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

Sky Highlights - April 2017

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Current Moon Phase



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