Bono Will Become Richest Rock Star on Planet by 4 PM

Bono will no longer breathe Paul McCartney's fumes in the money department ... by the close of trading today, he will become the richest rocker in the world, courtesy of Mark Zuckerberg and company.

Bono owns 2.3 percent of Facebook shares, through his investment group, Elevation Partners. The investment will be worth an estimated $1.5 billion by 4 PM ET -- not bad for a $90 million investment back in 2009.

McCartney's fortune is estimated at just a skosh over $1 billion, so Bono will be leaving the surviving Beatle in the dust.