Absolute magnitude and luminosity

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Two stars with the same absolute bolometric magnitude do not necessarily have the same absolute visual magnitude due to differences in their emitted radiation across wavelengths. Bolometric magnitude accounts for all radiation emitted, while visual magnitude focuses solely on the visible spectrum. Consequently, a hot star emitting primarily in the ultraviolet may have a higher bolometric magnitude than its visual magnitude, while a cooler star emitting mostly in the infrared would have a lower visual magnitude. The relationship between power output and magnitude is influenced by the stars' surface temperatures. Understanding these distinctions clarifies the complexities of stellar luminosity and visibility.
Rohan1997
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Do two stars of the same absolute bolometric magnitude have the same absolute visual magnitude?

If this is true; does this mean that two stars with the same power output have the same have the same bolometric magnitude and therefore same visual magnitude?
 
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Rohan1997 said:
Do two stars of the same absolute bolometric magnitude have the same absolute visual magnitude?

If this is true; does this mean that two stars with the same power output have the same have the same bolometric magnitude and therefore same visual magnitude?

When you say bolometric, it's about the radiation emitted at all wavelengths. Visual absolute magnitude, it's about the radiation emitted in the visible part of the spectrum. So you could have stars so hot that they emit the most of their radiation in the UV; for them, the bolometric magnitude would be much bigger than the visual magnitude. In the same way, cool stars would produce most of their radiation in the infrared and again, they would be barely visible (small absolute visual magnitude). It all depends on the surface temperature of the star.
 
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virgil1612 said:
When you say bolometric, it's about the radiation emitted at all wavelengths. Visual absolute magnitude, it's about the radiation emitted in the visible part of the spectrum. So you could have stars so hot that they emit the most of their radiation in the UV; for them, the bolometric magnitude would be much bigger than the visual magnitude. In the same way, cool stars would produce most of their radiation in the infrared and again, they would be barely visible (small absolute visual magnitude). It all depends on the surface temperature of the star.

Thank you this has filled the gap in my knowledge :)
 
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