This week's edition is presented by Guardian science correspondent Ian Sample. To discuss the big science stories of the week, Ian is joined by the Observer science team, Observer Tech Monthly commissioning editor and writer Nicola Davis and Observer Science editor Robin McKie. The team talks about the ill-fated polar explorer, no, not Alok Jha and his recent adventures, but John Franklin, the British Royal Navy officer who died with his crew in the Canadian Arctic in 1847. The team also discusses the awakening of Esa's Rosetta probe and why the African giant pouched rat is so good at sniffing out trouble.
Finally the Guardian's Pascal Wyse meets acoustician Trevor Cox to discuss the science of sound and his new book, Sonic Wonderland: A Scientific Odyssey of Sound.
