Assertion: star's companion | /r/HasProperty | sirius b
Facets:
Source sentences:
text: Its companion, Sirius B, is a star that has already evolved off the main sequence and become a white dwarf.
text: On January 31, 1862, American telescope-maker and astronomer Alvan Graham Clark first observed the faint companion, which is now called Sirius B, or affectionately "the Pup".
text: Its companion, Sirius B, is much smaller.