Thermal exhaust port/Legends

A Thermal Exhaust Port is, as the name suggests, an outlet for heat from starships and space-stations. They draw excess heat energy from the reactors and other equipment and expell it into space to prevent the crew from being cooked by heat build-up.

The Death Star I's thermal exhaust port was a major flaw in the design that the Rebels were able to exploit at the Battle of Yavin. The port was only two meters wide and lay at the end of a large trench in the hull of the battle station, and was ray-shielded against energy weapons such as laser cannons. It was through this flaw that Luke Skywalker fired a pair of proton torpedoes, causing the destruction of the battle station.