Free Astronomy Quiz

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  2. Terminology - B

As with any field of scientific study, astronomy has a long list of important terminology. So we've put together this glossary where you can check you fully understand the meaning of the common terms, as well as some of the more unusual words.



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



Words beginning with 'B' :



Background radiation : in astronomy refers to the microwave radiation coming from all directions. It is thought to be the remnant of the Big Bang.

Barlow lens : a lens used with other optics to increase the focal length of a telescope and thus the magnification of the eyepiece used.

Barycenter : the center of mass of astronomical objects orbiting each other.

Binary star : is a system of two stars orbiting their common barycenter. Viewed without a telescope some of those distant systems will appear as a single point of light.

Black hole : a region of space of extreme gravity from which even light cannot escape.

Blue giant : are massive stars in their slow burning stage before their death. They are stars at a specific time of their lives rather than being a specific type of star. They are rarer and smaller than red giants; they are really hot thus their blue colour. The blue giant stage is short lived and ends in a supernova forming either a neutron star or black hole.

Blue moon : is a second full moon in a calendar month or a third or fourth full moon in a season.




Resources :


To support the quizzes in each section, we've put together some extra resources to provide further information: