By Mark Abrams

PHILADELPHIA (CBS) — The Vatican-sponsored “World Meeting of Families,” scheduled to be held in Philadelphia next September, has announced an all-star lineup of speakers which will include three cardinals, several experts on family issues, and a hoped-for first visit of Pope Francis to the United States.

Philadelphia archbishop Charles Chaput has said he has every reason to believe the pope will be coming to Philadelphia next September, and it’s simply a matter of the Vatican making the formal announcement sometime early next year.

Donna Farrell, executive director of next year’s World Meeting of Families, says the group is planning for Pope Francis to arrive here near the end of the weeklong event, to participate in two key weekend events.

“The Festival of Families would take place on Saturday night, September 26th, in front of the Philadelphia Art Museum, on the Ben Franklin Parkway,” Farrell tells KYW Newsradio.  “And then, overnight, the stage would become an altar and on Sunday the papal mass would take place.”

Farrell says 1½ million people are expected to attend the concluding mass.

She says nearly 100 renowned speakers from around the world will make presentations in the Pennsylvania Convention Center in the days before the pope arrives.

“Cardinal Sean Patrick O’Malley, the archbishop of Boston, will be speaking. Some of our other speakers, though, are from other faith traditions,” she notes.

Farrell says they are planning for 10,000 to 15,000 delegates, coming from more than 150 countries, to attend the events week of events here.