Polar Stereographic Projection Flashcards
What projection is used by polar stereographic charts?
Plane.
How does scale vary on polar stereographic charts?
It expands with increasing distance from the pole, but is considered constant as the change is small.
How do:
(a) great circles
(b) rhumb lines
appear on polar stereographic charts?
(a) curves concave to the origin but are assumed to be straight lines
(b) curves concave to the pole and on the equatorial side of great circles
On a polar stereographic chart, when do great circle tracks and rhumb line tracks coincide?
When the track crosses the pole.
On polar stereographic charts, what is the curvature of great circle tracks proportional to?
Distance from the pole.
On polar stereographic charts, where is the parallel of origin?
At the pole.
What is the value of the convergence factor on polar stereographic charts?
1.
Define: convergency formula for polar stereographic projection.
Convergency = ∆λ
Define: vertex.
The point where a great circle track reaches the highest latitude.
At the vertex, RLT = GCT and the track is either 090°T or 270°T.
How to calculate the vertex between two meridians on the same latitude?
The vertex (highest latitude) will be reached half-way between the given meridians.
