(ANSA) - Catania, December 17 - Catania airport reopened Tuesday after authorities shut it down for two days after nearby Mount Etna erupted for the 17th time this year, spewing volcanic ash that could enter aircraft engines causing them to malfunction. It will take time for the Sicilian airport to get back to normal as it struggles with Christmas traffic congestion as well as passengers stranded during the eruption, authorities said. Some of the flights have been diverted to a smaller airport in the town of Comiso, which also reopened Tuesday. These are three Alitalia flights to Milan and Rome, and an Air One flight to Pisa.