then hoisted the massive shield flashing far and wide
like a full round moon – and gleaming bright as the light
that reaches sailors out at sea, the flare of a watchfire
burning strong in a lonely sheepfold up some mountain slope
when the gale-winds hurl the crew that fights against them
far over the fish-swarming sea, far from loved ones –
so the gleam from Achilles’ well-wrought blazoned shield
shot up and hit the skies.

– Homer

The Iliad, Book 19, lines 442-449. Homer describes in an epic simile how much of a gleam the shield of Achilles lets off as it lights up the skies. It is as bright as the blazing light that sailors glimpse at sea from a watchfire burning in an isolated farm in the mountains.