Premise: Canopus ( ), also designated Alpha Carinae (α Carinae, abbreviated Alpha Car, α Car), is the brightest star in the southern constellation of Carina, and the second-brightest star in the night-time sky, after Sirius. Canopus's visual magnitude is −0.74, and it has an absolute magnitude of −5.71.
Hypothesis: Sirius is the brightest star in the night sky.