Here's what will happen when Pope Francis dies

Only cardinals under the age of 80 are eligible to cast ballots. Around 120 will vote in secret for their chosen candidate, writing their name on a ballot and placing it in a chalice atop the altar.

If no candidate receives the required two-thirds majority, another round of voting takes place. There can be up to four rounds per day. The conclave that elected Pope Francis in 2013 took about 24 hours and five ballots, but the process can run longer; a conclave in the 13th century took about three years, while another in the 18th century took four months.

Once ballots are counted, they are burned in a stove inside the Sistine Chapel, installed ahead of time by Vatican firefighters. A second stove burns a chemical sending up a smoke signal through a chimney to the outside world: Black smoke means a new pope has not been selected, white smoke means one has.

The new pope

Once a pope is chosen, a representative from the College of Cardinals reads out the Latin announcement Habemus papam, meaning “We have a pope,” from the main balcony of St. Peter’s Basilica overlooking thousands of eager faithful.

Then the freshly elected pope, having chosen a papal name (most likely one honoring a saint or predecessor) and donned a white cassock, steps out onto the balcony to give his first address to the public. And with that, the Catholic world has a new leader.

Along with setting the church’s teachings and morals, the pope wields significant diplomatic and political power in world politics, acting as a mediator in global conflicts and guiding humanitarian efforts.

Most popes serve until the day they die. Pope Benedict XVI, who resigned in 2013, aged 85, because of declining health, was the first pontiff to step down in 600 years.

Ben Munster contributed to this report.