Can two stars have the same apparent but different absolute magnitudes

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SUMMARY

Two stars can indeed have the same apparent magnitudes while possessing different absolute magnitudes, and vice versa. Absolute magnitude is defined as the brightness of a star at a standard distance of 10 parsecs, while apparent magnitude varies based on the star's distance from Earth. A fainter star can appear equally bright as a brighter star if it is closer, and extinction can further influence apparent magnitude by dimming the light from distant stars. This discussion clarifies the relationship between absolute and apparent magnitudes in stellar observations.

PREREQUISITES
  • Understanding of absolute and apparent magnitudes in astronomy
  • Familiarity with the concept of distance in parsecs
  • Knowledge of light extinction and its effects on brightness
  • Basic principles of stellar luminosity
NEXT STEPS
  • Research the concept of light extinction and its impact on astronomical observations
  • Learn about the calculation of absolute magnitude using the distance modulus formula
  • Explore the significance of parsecs in measuring astronomical distances
  • Investigate the methods used to measure apparent magnitudes of stars
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Astronomy students, astrophysicists, and anyone interested in understanding the concepts of stellar brightness and distance measurements.

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Can two stars have the same apparent magnitudes but different absolute magnitudes?

what about if two stars have the same absolute magnitudes but different apparent magnitudes?
 
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Yes to both. Absolute magnitude is independent of distance (how far the star is from us), while apparent magnitude does depend on distance. A bright star very far from us will appear fainter than a less bright star very close to us.

For two stars with different absolute magnitudes to have the same apparent magnitude, the fainter star could be nearer to us and the brighter star could be farther from us.

For two stars with the same absolutely magnitude but different apparent magnitude, one star could be farther than the other.

Extinction (the absorption or scattering of light) also affects apparent magnitude by making a star appear dimmer.
 
Yes the two can have same absolute intensity and different relative magnitudes and vice versa.

As the light travels it spreads, and hence the intensity of light reaching the Earth lessens.
For a star near to us this spreading would be less and for a distant one would be more.So the star far away would seem to be fainter even if it has the same absolute intensity.
 
Apparent magnitude is the luminosity of any given star viewed from earth. Absolute magnitude is the comparative luminosity of stars viewed from the same distance.
 
Question

Could you please elaborate on the absolute intensity scale.
What is chosen as its base line or reference point??
 
anonymoussome said:
Could you please elaborate on the absolute intensity scale.
What is chosen as its base line or reference point??

Absolute magnitude is the visual magnitude the star would have at a distance of 10 parsecs(32.616 lightyears)
 
anonymoussome said:
Could you please elaborate on the absolute intensity scale.
What is chosen as its base line or reference point??

The absolute magnitude of a star is the apparent magnitude that the star would have if it were at a distance of 10 parsecs from the Earth, i.e., for stars at 10 parsecs,

absolute magnitude = apparaent magnitude.

[edit]Somehow (went some time without refreshing), I missed the reply by Janus[/edit]
 

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