Material: Stem cell trials, Archaeology & human remains, Interplanetary encounters: 14 Oct 2010

Stem cell trials - Geron's spinal cord therapy starts after years of regulatory wrangles. Human remains and archaeology - researchers complain of burdensome regulations. And a brief encounter with a comet chaser NASA's Deep Impact space probe is closing in on the Comet Hartley 2; Quentin hears about the science astronomers hope to learn from the encounter.