Apparent magnitude

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Asteroid 65 Cybele an twa starns, wi thair magnitudes labeled

The apparent magnitude (m) o a celestial body is a measur o its brichtness as seen bi an observer on Yird, adjustit tae the value it would hae in the absence o the atmosphere. The brichter the object appears, the lower the value of its magnitude. Generally the visible spectrum (vmag) is used as a basis for the apparent magnitude, but ither regions o the spectrum, such as the near-infrared J-band, are an aa uised. In the veesible spectrum Sirius is the brichtest starn in the nicht sky, whauras in the near-infrared J-band, Betelgeuse is the brichtest.