|
This is a list of the brightest naked eye stars to +2.50 magnitude, as determined by their ''maximum'', ''total'' or ''combined'' apparent visual magnitudes as seen from Earth. Although several of the brightest stars are also known close binary or multiple star systems, they do appear to the naked eye as single stars. The given list below combines/adds the magnitudes of bright individual components. ==List== Apparent visual magnitudes of the brightest star can also be compared to non-stellar objects in our Solar System. Here the maximum visible magnitudes above the brightest star, Sirius (-1.46), are as follows. Other than the Sun, the brightest object is the Moon (−12.7), Venus (−4.89), Jupiter (−2.94), Mars (−2.91), Mercury (−2.45), and Saturn (−0.49). Any exact order of the visual brightness of stars is not perfectly defined for the following reasons: * Stellar brightness were traditionally based on the apparent visual magnitude as perceived by the human eye, from the brightest stars of 1st magnitude to the faintest at 6th magnitude. Since the invention of the telescope and the discovery of double or binary stars meant that star brightness could be expressed as either ''individual'' (separate) or ''total'' (combined). The table is ordered by combined magnitude of all components that appear to the naked eye as if it were a single star, with the magnitudes of any individual components bright enough to make a detectable contribution included in parentheses. For example, the total or combined magnitude of the double star Alpha Centauri is −0.27, while its two component stars have magnitudes of +0.01 and +1.33. * New or more accurate photometry, standard filters, or adopting differing methods using standard stars can measure stellar magnitudes slightly differently. This can change the apparent order of lists of bright stars. The table shows V magnitudes, and is measured using a specific filter that closely approximates human vision. However, other kinds of magnitude systems do exist based on different wavelengths, some well away from the distribution of the visible wavelengths of light, and this effects the assumed apparent brightness. This generally explains the cause of magnitude variance in the literature. * There are sometimes small statistical variations in measured magnitudes; however, for most of the brightest stars, accurate photometry means brightness stays unchanged. These particular stars are sometimes called standard stars, which appear in the Catalogues of Fundamental Stars like the FK4, FK5 or FK6. * Some stars, like Betelgeuse and Antares, are variable stars, changing their magnitude over days, months or years. In the table, the range of variation is indicated with var. Magnitudes are expressed within the table are either when the stars are at maximum, or for the red variable stars, they are based on the mean brightness of the star when it is near maximum, which is general estimated over many observed light-curve cycles, sometimes lasting centuries. * The source of magnitudes cited in this list is the Wikipedia articles referenced - this list is simply a catalog of what Wikipedia itself documents. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「list of brightest stars」の詳細全文を読む スポンサード リンク
|