Houthis vow to continue attacking Israel in solidarity with the Palestinians after Israeli air strikes on Yemen. We ask the US envoy to Yemen, Tim Lenderking, where this escalation could lead. Also in the programme: NASA says it has successfully flown a space probe closer to the sun than ever before - one of its scientists tells us what happens next; and this year's Booker Prize winning novelist Samantha Harvey and the retired astronaut Cady Coleman discuss life on the International Space Station.