In the latest contribution to Radio 4’s “Illuminated” slot — for “one-off documentaries that shed light on hidden worlds” — the journalist and producer Lara Bullens visits the biggest settlement of the world’s northernmost community, Longyearbyen on the Arctic archipelago of Svalbard, as it celebrates the sun’s return after months of darkness. In The Frozen Light, she talks to residents and hears of “the gamble they take to experience, rather than endure, a unique corner of this earth, together”.