What Steps Are Missing in Deriving Pogson's Law?

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SUMMARY

The discussion focuses on deriving Pogson's Law, a mathematical relationship used in astronomy to express the difference in brightness between two celestial objects. The user has made significant progress by establishing equations that relate the magnitudes and brightness ratios of two objects using logarithmic functions. Key equations presented include the relationships between brightness (j) and magnitudes (m), specifically utilizing the base 10 logarithm and the constant 2.5. The user seeks assistance in identifying any missing steps in their derivation process.

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  • Understanding of logarithmic functions and their properties
  • Familiarity with Pogson's Law and its application in astronomy
  • Basic knowledge of celestial magnitudes and brightness ratios
  • Experience with mathematical derivations and algebraic manipulation
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  • Study the application of logarithmic identities in scientific calculations
  • Explore examples of brightness comparison in astronomy
  • Investigate common pitfalls in mathematical derivations involving logarithms
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Astronomy students, mathematicians, and anyone interested in understanding the mathematical foundations of brightness measurements in celestial objects.

71GA
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Hello i am strugling to derive Pogson's law, i feel i am soo close, but i am not there yet. Here is what i ve done soo far.


\begin{equation}
\begin{split}
j_6 \cdot 100 &= j_1\\
\frac{j_6}{j_1} &= \frac{1}{100}\\
\frac{j_6}{j_1} &= 10^{(-2)}\\
\frac{j_6}{j_1} &= 10^{-0,4\cdot 5}\\
\frac{j_6}{j_1} &= 10^{-0,4\cdot (m_6 - m_1)}\\
\frac{j_1}{j_2} &= 10^{-0,4\cdot (m_1 - m_2) }\\
\frac{j_1}{j_2} &= 10^{-0,4\cdot (m_1 - m_2) }\\
\frac{j_1}{j_2} &= 2,5^{-(m_1 - m_2) }\\
\log_{10} \frac{j_1}{j_2} &= \log_{10} 2,5^{-(m_1 - m_2) }\\
\log_{10} \frac{j_1}{j_2} &= -(m_1 - m_2) \cdot \log_{10} 2,5\\
(m_1 - m_2) &= -\frac{\log_{10} \frac{j_1}{j_2}}{\log_{10} 2,5}\\
\end{split}
\end{equation}

What am i missing?
 
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I already got it. TY
 

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