Absolute Visual Magnitude of Stars

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SUMMARY

The absolute visual magnitude of the Sun is approximately 4.8, while a particular star has an absolute visual magnitude of -0.29. Using the formula for luminosity comparison, the calculated luminosity ratio indicates that this star is about 109 times more luminous than the Sun. The correct answer to the multiple-choice question regarding how many times more luminous this star is than the Sun is closest to option (a) 100 times, despite a minor calculation error in using 4.81 instead of 4.8 for the Sun's magnitude.

PREREQUISITES
  • Understanding of absolute visual magnitude in astronomy
  • Familiarity with luminosity calculations
  • Knowledge of logarithmic functions and their applications
  • Basic grasp of spectral types of stars
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  • Study the formula for luminosity ratios in detail
  • Learn about the significance of absolute visual magnitude in stellar classification
  • Explore the relationship between spectral types and luminosity
  • Investigate common errors in astronomical calculations and how to avoid them
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Astronomy students, astrophysics researchers, and educators looking to deepen their understanding of stellar luminosity and absolute magnitude calculations.

Jimbob999
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Homework Statement


The Sun has an absolute visual magnitude of about 4.8 and a particular star has an absolute visual magnitude of –0.29. How many times more luminous is this star than the Sun, assuming these stars have similar spectral types and hence colours?

a) 100 times
b) 125 times
c) 150 times
d) 175 times
e) 200 times

Homework Equations


Luminosity of Star 1/ Luminosity of Star 2 = (100^1/5)^M2-M1
Where M1 and M2 are the abolute magnitudes

The Attempt at a Solution


[/B]
2.51^(4.81--0.29)
= 109 times more luminous

I am just wondering whether I have calculated correctly, given my answer is closest to a) but nearly crossing over to b)
 
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Your calculations appear to be okay to me (although you've used 4.81 rather than the given 4.8 for the Sun's absolute magnitude, a minor quibble that doesn't significantly impact your query).
 

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