Star
The Sun has an apparent magnitude of −26.7, but its absolute magnitude is only +4.83. Sirius, the brightest star in the night sky as seen from Earth, is approximately 23 times more luminous than the Sun, while Canopus, the second brightest star in the night sky with an absolute magnitude of −5.53, is approximately 14,000 times more luminous than the Sun. Despite Canopus being vastly more luminous than Sirius, however, Sirius appears brighter than Canopus. This is because Sirius is merely 8.6 light-years from the Earth, while Canopus is much farther away at a distance of 310 light-years.
Deneb
Deneb is the most luminous first magnitude star, that is, stars with apparent magnitude brighter than 1.5. Deneb is also the most distant of the 30 brightest stars by a factor of almost 2. Based on its temperature and luminosity, and also on direct measurements of its tiny angular diameter (a mere 0.002-second of arc), Deneb appears to have a diameter of about over 200 times that of the Sun; if placed at the center of the Solar System, Deneb would extend out to the orbit of the Earth. It is one of the largest known white stars.