ABC has revealed the identities of the 16 celebrities -- the show's largest cast ever -- who will be competing on Dancing with the Stars' ninth season this fall.

Dancing with the Stars host Tom Bergeron revealed the identities during ABC's Monday morning broadcast of Good Morning America.

The 16 celebrities who will compete for Dancing with the Stars' ninth-season mirror ball trophy will be singer Aaron Carter; Olympic gold medalist swimmer Natalie Coughlin; martial artist and Iron Chef America "The Chairman" host Mark Dacascos; indicted former House Majority Leader Tom DeLay; singer Macy Gray; Ashley Hamilton, the actor/singer son of former second-season Dancing with the Stars participant George Hamilton; actress Melissa Joan Hart; former supermodel Kathy Ireland; retired NFL star Michael Irvin; model and actress Joanna Krupa; UFC mixed martial arts fighter Chuck Liddell; actress Debi Mazar; singer Mya; former The Osbournes star Kelly Osbourne; entertainer Donny Osmond, the brother of former second-season Dancing with the Stars participant Marie Osmond; and professional snowboarder Louie Vito.

In addition to Dacascos and Osbourne, several of the other celebrity dancers also have previous reality ties -- including Irvin, who recently produced and hosted Spike TV's 4th and Long; Krupa, who recently competed in ABC's The Superstars; and Aaron Carter, who co-starred in E!'s House of Carters with his siblings in 2006.

Although the celebrities will learn their identities before then, ABC will publicly announce each celebrity's professional partner next Monday.

"Do you know who my partner is?" Osmond, who was present for the Good Morning America announcement, asked Bergeron after his Dancing with the Stars participation was revealed.

"Ah... no.  I honestly don't," Bergeron replied.

"I find out tomorrow," Osmond responded.

"I think they do today," Bergeron said.

Dancing with the Stars' ninth season will premiere with a two-hour performance episode on Monday, September 21 at 8PM ET/PT.