Catholic cardinals are gathering at the Vatican to elect the successor to Pope Francis, who died on April 21. Voting will take place in the Sistine Chapel, with ballots continuing in succession until any candidate secures two-thirds of the available votes.

If no clear choice has emerged after three days, balloting is suspended for 24 hours to allow cardinal electors time to reflect. Since 1831, no conclave has lasted more than four days.

The end of each round of balloting will be signaled by smoke emanating from a stovepipe chimney atop the Sistine Chapel. Black smoke — fumata nera in Italian — indicates an inconclusive vote, while white smoke — fumata bianca — will signify that a new pope has been elected, as will the ringing of the bells of St. Peter’s Basilica.