Could Venus actually be very similar to Earth? That is a hot topic of discussion at the International Venus Conference. On this week's Material World, Quentin Cooper finds out if the two planets may at one time have been almost identical. The Pine Island Glacier is the biggest in Western Antarctica - but it is not as big as it used to be. It is melting because of the warming waters surrounding it. The annual ice loss is estimated tens of billions of tonnes which adds nearly a millimetre to sea levels every year. New research, published in the journal Nature Geoscience suggests that the rate of ice loss is speeding up because it's no longer held back by a rocky ridge. Dr. Adrian Jenkins from the British Antarctic Survey is the lead author of this latest study and joins Quentin on the programme. The simulated mission to Mars is now well underway in Russia. 6 volunteers are making themselves at home on the 520 day experiment which will help scientists prepare for a real mission to the Red Planet in the future: Dr. Patrik Sundblad the Director of Human Spaceflight at the European Space Research and Technology Centre tells Quentin how things are going so far. Quentin also catches up with "So you want to be a scientist" finalist Sam O'kell and Professor Geoff Lawday as Sam prepares to test out his specially built pressure suit at the Roskilde Music Festival in Denmark - one of the biggest in Europe. Producer: Martin Redfern.