I have always taken an interest in intertemporal communication related projects like the clock of the long now, the Chronophage clock or the LAGEOS / Voyager and Pioneer satellite plaques etc.

I was not aware of the artistic endeavour below which I saw in the news today - I think even I could mange to keep up with the key changes in this one...

Fans have flocked to a church in Germany to hear a chord change in a musical composition that lasts for 639 years. It is the first change in the piece, As Slow As Possible, in seven years. The work is by the avant-garde American composer, John Cage. It began 19 years ago with a pause lasting nearly 18 months. The change of chord took place on the specially built organ on which the composition is being performed. The Saint Burchardi Church in the city of Halberstadt started playing the music in 2001 and the last note change took place in 2013.The score is made up of eight pages of music, to be played at the piano or organ - very slowly. But the wait for the next scheduled chord change will be quick in comparison - with 5 February 2022 slated as the date. The piece will end in 2640. Cage, who died in 1992 at the age of 79, wrote the piece in the 1980s. The composer is arguably most famous for 4'33". The three-movement composition from 1952 is for any combination of instruments, but instructs performers not to play them. Listeners instead hear the sound of the surrounding environment during the four minutes and 33 seconds the work lasts.

https://www.bbc.co.uk/news/world-europe-54041568


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