NEW YORK: What is happiness? The United Nations is teaming up with pop stars to create a playlist that asks, in musical form, that eternal question.

A campaign launched Monday is asking listeners around the world to post through social media the songs that make them happy, with the playlist to be revealed Friday on the UN-declared International Day of Happiness.

The curators who will assess the responses and determine the playlist include the British singer-songwriters Ed Sheeran and James Blunt, US singer-songwriter John Legend, French DJ David Guetta and the Portuguese pop star David Carreira.

UN Secretary-General Ban Ki-moon, who is not generally known for his rock star persona, announced the initiative in an MTV-style video in which he offered his vote for Stevie Wonder’s 1970 hit “Signed, Sealed, Delivered.”