A Panic Button is a single-shot emergency beacon employed by all the UNSC armed forces. It has two settings: The 'Red' setting sent out a distress signal, informing allies that the team's mission has failed and they need immediate assistance. The 'Green' signal merely activates a homing beacon to inform UNSC forces of the location of a hidden objective.
In 2525, the Spartans used a Panic Button to mark a homing beacon on Eridanus secundus. Despite this, the asteroid base survived until 2552. However, since the UNSC was in the middle of the Human-Covenant war, it is probable it didn't have time to deal with a group of pirates.