Photo by Dave Benett/Getty Images

U2’s big debut at the Las Vegas Sphere included a brief tribute to Sinead O’Connor.

Bono paid tribute to his fellow Irish singer by singing “Nothing Compares 2 U” at the final line of their song “With Or Without You” while looking up at the sky.

O’Connor died in July at the age of 56.  Bono attended her funeral procession the following month.