How do you convert from LA to CI system using right ascension and declination?

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SUMMARY

The discussion focuses on converting from the Local Astronomic (LA) system to the Conventional Inertial (CI) system using specific mathematical transformations. The equation provided for this conversion is r^{CI}= r^{LA}/(P1*R2(90-Ф)*R3(Λ)*R2(-xp)*R1(-yp)*R3(GAST)*N*P). The user initially misinterpreted the notation, confusing "CL" with "CI." The correct approach involves taking logarithms and rearranging the equation to isolate CI. Additionally, the user seeks guidance on computing CI using right ascension and declination.

PREREQUISITES
  • Understanding of Local Astronomic (LA) and Conventional Inertial (CI) coordinate systems
  • Familiarity with MATLAB for mathematical computations
  • Knowledge of rotation matrices and their applications in astronomy
  • Basic logarithmic functions and their properties
NEXT STEPS
  • Research the application of rotation matrices in astronomical coordinate transformations
  • Learn how to implement the transformation equations in MATLAB
  • Study the concepts of right ascension and declination in celestial navigation
  • Explore advanced topics in astrodynamics related to inertial reference frames
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Astronomy students, astrophysicists, and software developers working on astronomical simulations or coordinate transformations.

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Homework Statement



I was given a question to transform the LA system to the CI system. (Local astronomic and Conventional Inertial)

Homework Equations



r^LA=P1*R2(90-Ф)*R3(Λ)*R2(-xp)*R1(-yp)*R3(GAST)*N*P*r^CL


The Attempt at a Solution



I attempted this on MATLAB but I used the wrong rotation and got the question wrong so I was wondering if anyone knew how to convert LA -> CI
 
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I see "LA" on the left side of the equation but I see no "CI". Was the "CL" on the right supposed to be "CI"?

If so, first divide both sides by all the numbers on the right to get
r^{CI}= \frac{r^{LA}}{P1*R2(90-Ф)*R3(Λ)*R2(-xp)*R1(-yp)*R3(GAST)*N*P}

Now, take the logarithm of both sides (it doesn't matter what base)
CI log(r)= LA log(r)- log(P1*R2(90-Ф)*R3(Λ)*R2(-xp)*R1(-yp)*R3(GAST)*N*P)
Finally, divide both sides by log(r) to get
CI= LA- \frac{log(P1*R2(90-Ф)*R3(Λ)*R2(-xp)*R1(-yp)*R3(GAST)*N*P)}{log(r)}
 
HallsofIvy said:
I see "LA" on the left side of the equation but I see no "CI". Was the "CL" on the right supposed to be "CI"?

If so, first divide both sides by all the numbers on the right to get
r^{CI}= \frac{r^{LA}}{P1*R2(90-Ф)*R3(Λ)*R2(-xp)*R1(-yp)*R3(GAST)*N*P}

Now, take the logarithm of both sides (it doesn't matter what base)
CI log(r)= LA log(r)- log(P1*R2(90-Ф)*R3(Λ)*R2(-xp)*R1(-yp)*R3(GAST)*N*P)
Finally, divide both sides by log(r) to get
CI= LA- \frac{log(P1*R2(90-Ф)*R3(Λ)*R2(-xp)*R1(-yp)*R3(GAST)*N*P)}{log(r)}

Yes, that is correct I was confusing myself, sorry xD.

I have another question in order to find the CI using right ascension and declination. How would I be able to compute that?

Thanks!

Maybe I should be in the astronomy section xD
 
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