How they'll pick a new Pope to clean up after Benedict

CATHOLIC cardinals have assembled in Rome to begin "sketching an identikit" for the next Pope and to ponder "who among them might be best to lead a church beset by crises," reports Reuters. But how will Pope Benedict's replacement be chosen, how long will it take and will his sometimes controversial tenure and dramatic resignation inform the appointment of his successor?

It won't be a quick process. The job of choosing a new Pope began in earnest today with the first in a series of daily meetings known as general congregations. The cardinals use the events to "meet, mingle and size each other up", reports The Guardian. Top of the agenda will be deciding the date on which the 115 cardinal electors – those under the age of 80 – go into the Vatican's Sistine chapel and begin the centuries-old ritual known as a conclave at which the new Pope will be chosen. The conclave is expected to begin on Monday, because the Vatican is aiming to have a new pope elected "next week" and officially installed several days later. That will allow him to preside over the Holy Week ceremonies starting with Palm Sunday on March 24 and culminating in Easter the following Sunday, says Reuters.

The conclave is incredibly secretive. The cardinals will be alone in the chapel apart from a few servants and emergency medical staff. They eat, vote and sleep within "sealed areas", says the Daily Telegraph, and there is no contact with the outside world. Anyone breaking the vow of silence would face excommunication, so a leak is extremely unlikely.

The voting system is complicated. When voting begins, two ballots are held each morning and two each afternoon. The voting goes on for up to three days until a two-thirds majority is reached. The cardinals write their choice on a ballot paper and place it in an urn. The votes are added up by scrutineers, and, if there are no irregularities, the result is recorded and the ballot papers burned.

Coloured smoke signals a result. The colour of the smoke from the chapel's stovepipe indicates the status of the vote. If the smoke is dark – an effect that used to be achieved using damp straw, but has involved a dye since 1963 - there has to be another vote. If it's white, it means the cardinals have picked their man.

Benedict's legacy will inform the choice. Many cardinals will be looking for a leader who will "clean up the mess left by Benedict's crisis-hit papacy" says The Guardian. But that doesn't mean the choice is clear. There is no obvious frontrunner – despite the what the bookies say – and about a dozen candidates are said to be papabile (literally, pope-able). ·