Sirius-A is the brightest extrasolar star visible to the naked eye from Earth, being almost twice as bright as the second brightest, Canopus.  Sirius-A and Sirius-B combine to form a binary system and appear as one star to the naked eye, though the vast majority of luminosity to the naked eye comes from Sirius-A, Sirius-B being a white dwarf which is only around 30 AU (astronomical units) away from Sirius-A.  It is also theorized that there is a Sirius-C, but to date, this has not been proven.  Sirius A and B (and possibly C) combine to form a bright point known as Sirius or the “Dog Star”. *looks at J.K. Rowling*

Sirius-A is a white main sequence star (A1V) that is about twice the size of our Sun. The extreme brightness from our point of view comes not so much because it is a particularly bright star, but rather because it is only 8.6 light years away (2.6 parsecs).  That’s a really long ways away by standards of distance we normally deal with, but by galactic standards, it’s just next door and is one of our nearest neighbors.

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