Polaris and me

Looking into the night sky in the northern hemisphere our major signpost is Polaris.

When you know the pointer stars, it is easy to find, it lays due north, whatever your location in the Northern hemisphere. If you were to take a line from your position down to the centre of the earth, and then continue that line at 90º from the centre of the earth it would meet up with Polaris. This is a constant, no matter what latitude you are from 0º to 90º

Knowing your latitude will allow you to set up your viewing instrument to that angle, in the picture above the location is 45º therefore by setting the incline of your telescope, Polaris will be viewed at 45º in a Northerly direction.

(The reverse method was used by sailors to calculate their latitude on the open seas, using a sextant, they took the angle of degrees of Polaris above the horizon, there was their latitude in the northern hemisphere)

Below is another way of finding Polaris, look north for the Plough, or Big Dipper two of the pan stars furthest from the handle, will lead a slight arc line to Polaris on through to the distinctive "W" formation of Cassiopeia

The orientation around the stars will be dependant on the time of viewing.

Remember that stars rotate anti-clockwise around Polaris

So to recap, we have covered Latitude, and it's relation with our Pole star Polaris. How it can be used crudely for navigation given both northerly direction and latitude above the equator.

Finally how by looking further out, it's relationship with both The Plough and Cassiopeia