How do I approximately calculate the sidereal time at an specific location in a specific time and month ? Most formulas required to input a year too, and then they want you to deal with Julian day, etc. but these are not things I have seen, instead what would be a simple approximation when you don't have the year?
As an example, on the 20 March, at coordinates 6°E,52°N (if needed 9° west to the center of the time zone) what is the approximate sidereal time at astronomical midnight?
I know that astronomical midnight is 24h 36 min at that location (calculated by considering that a sidereal day is approx 23h56m and that when it is midnight at the center of the time zone, the point 9° west to the center of the time zone still has to to move for 9°*((23h56m)/360°))=36 min approx.)
The definition of sidereal time is the right Ascension which at any given moment crosses the meridian in direction due South. But I can't figure out how to get to the sidereal time from this.
