Looking for a lullaby

On the far side of the galaxy, just past the Milky Way, rests a very strange planet, indeed a planet full of green soup volcanos, Music Trees, and adorable, cuddly creatures called The Clangers. The Clangers live in underground burrows and speak to each other by whistling a tune. And every night, the Iron Chicken sings a very special lullaby that lulls the Clangers to sleep.