Golden Hour Calculator

Golden hour and blue hour are bands of solar altitude, not fixed hours: golden runs from four degrees below the horizon to six above it, and blue from six below to four below. Enter a date, a latitude and longitude and the UTC offset in force that day, and this returns both golden windows, both blue windows, sunrise, sunset, solar noon and civil, nautical and astronomical twilight. There is no place lookup, so the coordinates and the offset are yours to supply. At high latitudes the sun may never cross one edge of a band, and it says so rather than inventing a time.