Red giant

The red giant was one stage in the expansion of a star.

In the year 5000000000, Earth's sun "blossomed", as Cassandra O'Brien.Δ17 put it, into a red giant, finally resulting in the destruction of Earth. Gravity satellites had held back the sun until the National Trust ran out of money. (TV: The End of the World)

The Fifth Doctor and Amy were once on board a ship on a collision course with Leboon, then in the red giant stage of its life. (AUDIO: The Judgement of Isskar)

The sun of Proamon had been a red giant and became a supernova a thousand years later. (TV: Dragonfire)