Plans are taking shape for the day when a global coalition may have to "hack the planet" in a bid to reverse the ravages of global warming. Proposals to cool the Earth by deploying sunshades or sucking carbon dioxide from the atmosphere were considered fanciful just a few years ago, but are now being considered by politicians in the US and UK. At a gathering of key scientists and policy experts held in Asilomar, California, detailed debates began over who should control the development of a planetary rescue plan.