By Robbie Gibb, programme producer
Presented by Jeremy Paxman
North Korea has stepped up its military might
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We hate doing stories about North Korea. How do you report intelligently from a completely closed and highly secretive society?
With great difficulty is the usual answer, but when that country explodes a nuclear bomb, then it's no longer a country you can safely ignore.
If that's how we felt after this morning's news, that's probably also the mood across the world in the diplomats' drawing room and the officers' mess, as everyone struggles to come to grips with a threat that cannot yet be quantified.
We've got Tim Whewell on the case and Laura Trevelyan at the United Nations.
A much better known quantity is President Bashar al-Assad of Syria.
Painted by the west as a terrorist sponsor and, if not quite part of the axis of evil then something pretty close, what must it be like to lead a secular Arab state through the era of the War on Terror?
President Assad talks exclusively to the BBC's John Simpson.
And where do you stand on Goldilocks theory? That, as every Newsnight viewer knows, is the proposition that the universe has just the right conditions (not too hot, not too cold) to allow life to form.
Is it proof of God, proof of lots of universes, or just proof that some people have too much time on their hands?
Our Science Editor Susan Watts does the heavy lifting so you don't have to.
Read extracts and review Paul Davies' The Goldilocks Enigma.
And Martha Kearney is at Westminster as Parliament returns, to report on John Reid and the prisons crisis.