Catching the Sun: Sorted!

When is sunrise? This was the puzzle I had to solve when I embarked on my sunrise walks way back on the winter Solstice (105 days ago!) 


How would you feel if you were confronted by this as an answer?


'Using local time it is theoretically easy to figure out when the Sun rises. You work out its declination from the time of the year it is. Then you work out how long an object at that declination is up in the sky for given your lattitude on Earth. Then you subtract approximately half of that time from local noon to find the local time at which the sun rises. Of course we don't use local time - we have time zones in which the time is defined to be the same for a certain area of the Earth. Only in the exact centre of that time zone is the time equal to local time. So you also need to know your longitude to know the difference between your local time and the time you use on your watch.'


I've simplified it! Count it as the moment when I first see the sun. Take this morning, officially sunrise was 6.33 but this was my first glimpse of the sun - 7.20 - sorted!