Fifty years ago, the launch of Russia's Sputnik satellite kick-started the space age. In this special edition podcast, we reflect on half a century of space exploration, hear from veteran astronaut Jeff Hoffman about what it's like to blast into space, and find out why our future might not lie on planet Earth

The US is the world's biggest emitter of greenhouse gases and the nation that can do the most to slow the impact of global warming. In this special edition podcast we explore American attitudes to climate change and bust some common climate myths.

Professor Richard Wiseman takes us on a tour of the weird, the wonderful and the human mind. Also this week: Uncovering the true story behind America's origins, and just how do our dogs perceive us?

New developments in brain science shed light on how our minds grapple with decisions, large and small. Also this week, astronomers have another chance to witness the great supernovae of history and why "carbs" (like bread, rice and potatoes) are white, while carbon is black.

What can the precariously balanced boulders of California and Nevada tell us about predicting the next big earthquake there? Also this week: astronomers discover the most Earth-like exoplanet yet, and our Last Word column considers an evolutionary explanation for why sheep are notorious road hogs

Epidemiologist Gilbert Burham ignited controversy after publishing figures suggesting the number of people killed by the war in Iraq is far higher than coalition forces have acknowledged - he defends his survey. Also this week: teen transexuals helped and sterile neutrinos hunted.