How much brighter is the magnitude 2 star than the 12 magnitude star?
Could you explain the formula?Which is brighter in our sky, a star with apparent magnitude 2 or a star with apparent magnitude 12?Magnitude 2 star is brighter than magn.12 star by 10,000 times.
In the beginning people started using the term 'First magnitude' for the the brightest 20 (Sirius, Canopus, Rigil Kentaurus, Arcturus, Vega, Capella, Rigel, Procyon, Achernar, Betelgeuse, Hadar (Beta Centauri), Altair, Aldebaran, Antares, Spica, Pollux, Fomalhaut, Deneb, Beta Crucis, Regulus), rather loosely.
Then the next 50 or so, as 'second magnitude' and so on. As per Hipparchus (120 BC) the faintest (just barely visible to naked eye) are classed 'sixth magnitude'.
In 1856, NG Pogson proposed that the difference of five magnitudes corresponds to a ratio (first to sixth) of 100. That is, there is particular ratio ('m') between successive magnitudes which when multiplied by itself if it is two magnitudes, so on till it multiplies itself 5 times over (it is not multiplied by 5, but , m X m X m X m X m) or 'm^5 '.
That is m^5 = 100. If we take logs on both sides
5 log m = log 100 = 2
log m = 0.4.
Antilog of 0.4 (that is 10^0.4) = 2.511886...
As we have already started with a scale that increases in direct proportion to feebleness, higher the magnitude number fainter the star.
When the brightness of each star was scientifically measured by 'photometry', some extermely bright stars have crossed over 'zero' and have negative numbered magnitudes. These are
Sirius (-1.46), Canopus (-0.72), Rigil Kent (-0.06), Achernar (-0.04).
Formula is
(2.512) ^[-m] gives the relative brightness. A star with 0.00 magnitude is the reference.Which is brighter in our sky, a star with apparent magnitude 2 or a star with apparent magnitude 12?I believe that would be the star with the magnitude of 2.
The way it works is, the higher the number, the fainter the star
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