List of most luminous stars

Below is a list of stars arranged in order of decreasing luminosity (increasing bolometric magnitude). Accurate measurement of stellar luminosities is quite difficult in practice, even when the apparent magnitude is measured accurately, for four reasons:

Because of all these problems, other references may give very different lists of the most luminous stars (different ordering or different stars altogether). Data on different stars can be of somewhat different reliability, depending on the attention one particular star has received as well as largely differing physical difficulties in analysis (see the Pistol Star for an example). The last stars in the list are familiar nearby stars put there for comparison, and not among the most luminous known. It may also interest the reader to know that the Sun is more luminous than approximately 95% of all known stars in the local neighborhood (out to, say, a few hundred light years), due to enormous numbers of somewhat less massive stars that are cooler and often much less luminous. For perspective, the overall range of stellar luminosities runs from dwarfs less than 1/10,000th as luminous as the Sun, to supergiants over 1,000,000 times more luminous.

This list is currently limited mostly to galactic and Magellanic Cloud objects, but a few stars in other local group galaxies can now be examined in enough detail to determine the luminosities. As of mid-2012 the list is more or less complete for stars down to 1,000,000 times the luminosity of the Sun. Some suspected binaries in this magnitude range are excluded because there is insufficient information about the luminosity of the individual components. Selected fainter stars are also shown for comparison.

Despite their extreme luminosity, many of these stars are nevertheless too distant to be observed with the naked eye. Stars that are at least sometimes visible to the unaided eye have their apparent magnitude (6.5 or brighter) highlighted in blue.

Note that even the most luminous stars are much less luminous than the more luminous persistent extragalactic objects, such as quasars. For example, 3C 273 has an average apparent magnitude of 12.8 (when observing with a telescope), but an absolute magnitude of −26.7. If this object were 10 parsecs away from Earth it would appear nearly as bright in the sky as the Sun (apparent magnitude −26.74). This quasar's luminosity is, therefore, about 2 trillion (10¹²) times that of the Sun, or about 100 times that of the total light of average large galaxies like our Milky Way. (Note that quasars often vary somewhat in luminosity.)

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