Songs of Distant Earth by Arthur.C.Clarke

Loren Lorenson is a refugee from a destroyed Earth, aboard the Starship Magellan, the last to flee the solar-system before the sun goes nova, the lucky few who were given a place in her berths observe the demise of the Earth before entering hibernation for a decade long journey to a new home.
In order to make the journey in safety Magellan huddles behind a debris shield made of ice. The shield however would not survive the entire journey and must be replenished from a convenient source. The planet Thalassa would serve well as a way station for the crew to disembark for a few weeks on a world that colonised not long ago had been silent for generations and was believed to be no longer inhabited. On arrival the crew discovers that far from being extinct the human colony has flourished in it's own modest way in the idyllic climate of the planets three islands. In order to cause minimal disruption to the native culture the crew sent to Thalassa is quartered separately and the ice producing plant is placed n a distant shore. Despite the enforced separation the planet side crew builds many friendships and Loren falls in love.