A planet whose people sent a probe into space to preserve the memory of their world before its sun destroyed it.
Kataan was the inhabited planet of a peaceful civilization that died about a thousand years before the Enterprise's encounter with its probe. Its star grew increasingly hot, causing long droughts and eventually a nova that wiped out life on the planet.
In The Inner Light, the Kataan probe links with Picard and lets him live a lifetime as Kamin in the community of Ressik. Through his experience the people of Kataan ensured that someone would remember them. Picard keeps a flute he played in that life.