Great circles (23-05-18) Flashcards
What is a great circle?
a circle around the earth with radius and centre matching that of the Earth.
What is a small circle?
Any circle that is not a great circle.
How many great circle options do antipodal points have?
infinite
What is a loxoddrome/loxodromic line?
A rhumb line from the equator to a pole, which causes a spiral track.
What is a rhumb line?
A line connecting 2 positions that crosses all meridians at the same angle relative to north.
When comparing rhumb lines and great circles, which is always closer to the nearest pole?
A great circle.
When do great circles and rhumb lines intersect?
At the equator.
What is geocentric latitude?
latitude measured at the centre of the earth from the equator.
What is geodetic/geographic latitude?
latitude measure at a point off set from the centre of the earth which intersects the earths surface at 90degrees, due to the elliptic profile of the Earth.
Where is the maximum difference between geodetic and geocentric latitudes found, and what is the maximum difference?
it is found at 45degN/S and the difference is 11.6’ of arc.
At what latitude is the arctic circle found?
66.5degN
At what latitude is the Tropic of Cancer found?
23.5degN
At what latitude is the equator found?
00degN/S
At what latitude is the Tropic of Capricorn found?
23.5degS
At what latitude is the Antarctic circle found?
66.5degS