Our weekly news round-up: Cassini has only 3 orbits to go before being deliberately crashed into Saturn's atmosphere on September 15; AI and robotics experts call on UN to ban killer robots; Add-ons for your smart phone turn it into a mini lab to measure everything from heavy metals through to detecting and monitoring malaria and ebola and tracking antibiotic resistance; NASA signs contract with BWXT to revisit use of nuclear thermal propulsion; Federal Court blocks 59 pirate movie sites and 127 domains; Optus and Telstra offer refunds for where advertised NBN speeds were not met; MoviePass lets you see a movie a day for US$30/month - in the US; Adelaide high school students win Robotic Olympics.