how to work out latitude and longitude
Your current position is S 41o 17’02.9” E 174o 46’ 05.6”
Latitude and longitude are both required to identify an exact location. A place’s latitude, location north or south of the equator, can be determined by observing the sun and stars.
However, to gauge longitude, or the east/west position, you must know both the time at a reference point (Greenwich Mean Time) and the time at your current location. Since time is calculated by how long it takes the earth to rotate every 24 hours – one hour for every 15o turn – the two times allow navigators to compute the angle on the earth where they are located: their longitude.
How it works:
New Zealand is 12 hours ahead of Greenwich Mean Time.
Using the equation: 12 hours (difference between the two times) x 15o = 180o, we find that New Zealand is near enough to 180o longitude.
I learnt all that from the observatory board – so why not share it here as well...