Dienstag aus Licht Dienstag aus Licht Dienstag aus Licht (Tuesday from Light) is an opera by Karlheinz Stockhausen in a greeting and two acts, with a farewell, and was the fourth of seven to be completed for the opera cycle "Licht: die sieben Tage der Woche" (Light: The Seven Days of the Week). It was begun in 1977 and completed from 1988 to 1991, to a libretto by the composer. "Dienstag" is an opera for 17 solo performers (three singers, 10 instrumentalists, 4 dancer-mimes), actors, mimes, choir, orchestra, and electronic music. Tuesday is the red day of conflict between Michael and Lucifer .
Determination of the day of the week since the start of the century, and then add these together along with the number of years since the start of the century, and the day number of the month. Eventually, one ends up with a day-count to which one applies modulo 7 to determine the day of the week of the date. Some methods do all the additions first and then cast out sevens, whereas others cast them out at each step, as in Lewis Carroll's method. Either way is quite viable: the former is easier for calculators and computer programs; the latter for mental calculation (it is quite