Determining Lat, Long using trigonometry

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Determining latitude and longitude using spherical trigonometry involves understanding the relationships between the vertices of a spherical triangle formed by the True North Pole, the Geomagnetic North Pole, and a specific location. The known distance between the True North Pole and the Geomagnetic North Pole is 820.76 km, which translates to an angle of 0.13 radians or 7.38°. The discussion revolves around applying the law of sines to find the remaining lengths and angles of the triangle, which could lead to calculating the coordinates of the unknown location. There is some uncertainty about the correct application of the law of sines, particularly regarding the relationships between the angles and sides. Overall, the feasibility of determining the coordinates hinges on correctly applying spherical trigonometric identities.
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I am not sure if this is entirely possible, as my spherical trig skills are lacking.

Would it be possible to determine the Lat and Long coordinates for a position on the Earth knowing the following.

  1. True North Pole is at 90°N
  2. Geomagnetic North Pole is at 82.7°N, 114.4°W
  3. Knowing the direction of True North, I can determine the angle separating the two at my position.

The vertices of the spherical triangle would be.
  1. Point A would be the True North Pole.
  2. Point B would be the Geomagnetic North Pole.
  3. Point C would be my location.

The sides of the spherical triangle would be.
  1. Line AB, or γ
  2. Line BC, or α
  3. Line AC, or β

Side γ has a known length, the distance from the True Pole to GM Pole, which is 820.76km. With Earth's radius at 6371km, this works out to be 0.13 radians, or 7.38°.

sin C/sin γ = -1.07703 = sin A/sin α = sin B/sin β Correct?

Seems to me the other lengths should be able to be determined, and then perhaps the coordinates of Point C. Is that possible?
 
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Insanity said:
Side γ has a known length, the distance from the True Pole to GM Pole, which is 820.76km. With Earth's radius at 6371km, this works out to be 0.13 radians, or 7.38°.

sin C/sin γ = -1.07703 = sin A/sin α = sin B/sin β Correct?

Maybe I have the law of sines upside down?

C is the angle between vertices, γ is the length of the opposite side in degrees, so then

sin γ/sin C = -0.92848

I know the lat, long of two vertices, A and B, of the triangle, and the length of one side γ, and the angle of its opposite vertice C.
 

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