Big Bang: Spectacular cosmic discovery hailed

Scientists say they have extraordinary new evidence to support a Big Bang Theory for the origin of the Universe.

Researchers believe they have found the signal left in the sky by the super-rapid expansion of space that must have occurred just fractions of a second after everything came into being.

It takes the form of a distinctive twist in the oldest light detectable with telescopes.

The BBC's science editor David Shukman reports.