The global impact of energy price rises

It has been a day of turmoil on the world's financial markets after Israel - on Wednesday - struck an Iranian facility in the South Pars gas field, part of the world's biggest natural gas field, which Iran shares with Qatar. That, in turn, prompted Iran to retaliate against energy facilities in Qatar and its other Gulf neighbours sending the price of both gas and oil surging upwards. Also in the programme: a mysterious signal is being broadcast in the Farsi language on shortwave radio from Europe - what is it? And how a conversation in the Caribbean Sea about...