Two of the music industry's megastars, Rihanna and Jennifer Lopez, have just been added to the list of performers at the Billboard Music Awards. They join a list that already includes the Black Eyed Peas and Lady Antebellum.

The show will take place in Las Vegas on May 22. For Rihanna, the performance is yet another notch in her belt, as the singer seems to have performed at almost every major awards show over the last year. She's already performed at the 2011 Grammys, the 2011 Brit Awards and the NBA All-Star game. Last year, she performed at the 2010 American Music Awards.

J-Lo will likely treat fans to a performance of her new single, "On the Floor."

(Photos, from left: Kevin Winter/Getty Images, John Ricard/Retna Ltd.)