HOLLYWOOD, Calif. — Homer, Bart, Lisa, Marge and Maggie Simpson were all on hand Sunday night to celebrate 20 years of The Simpsons at the Barker Hangar in Santa Monica.

The Fox series is the longest-running American sitcom, the longest-running American animated program, and it recently surpassed Gunsmoke as the longest-running American primetime scripted entertainment program.

"You know, it's really weird," Matt Groening, the show's creator, told the Associated Press. "I mean, I thought the show would be successful. But the fact that we're still standing here some 20 years later and talking about it is very peculiar. But very happy."

Click here to check out photos of your favorite stars at the event.