Taking in epidemics of nostalgia in the 18th century, NASA scientists looking at homesick astronauts, and generations of homesickness in refugee camps, travel writer Gail Tolley considers why home – and leaving it – is a far more complex experience than is often understood. Inspired by her childhood experience of homesickness, she argues that the condition is being felt particularly acutely in the 21st century, and looks for ways of relieving some of its symptoms.