Republican debate: Presidential candidates tear in to absent Donald Trump in Iowa

Even in boycotting a debate with his Republican rivals, front-runner Donald Trump managed to upstage the event on 28 January with a typical dramatic flourish. Instead of attending a seventh debate, the former reality TV star held a competing event across town that he said raised $6m (£4m) for US military veterans. In doing so, he cast a shadow over his rivals, who frequently tossed barbs his way. Jan 29, 2016

Doomsday Clock remains at three minutes to midnight

Continued threats from climate change and nuclear arsenals prompted the scientists who maintain the Doomsday Clock, a symbolic countdown to global catastrophe, to keep the clock at three minutes to midnight. Jan 27, 2016

How Niagara Falls could be turned off…again

New York State officials are considering turning off the American Falls, one of three waterfalls that make up the Niagara Falls, for several months in order to replace two old stone arch bridges, reported Buffalo news. Jan 26, 2016