7000lb, Thermo-Nuclear, Yellow Sun, Practice, Inert

Yellow Sun was the first thermonuclear weapon developed for operational service in the United Kingdom. Yellow Sun Mk1 was essentially a boosted fission weapon with a yield of about 500Kt. Yellow Sun Mk2 had a larger yield of 1Mt. The name referred to the bomb's casing, which could contain various different warheads.

Yellow Sun was carried by the RAF V-Bombers Victor, Vulcan and Valiant.