|Sister Earth? We may need Keppler 22b - if only we can develop warp travel (solar powered!)|
This advert for BBC Natural History programmes played at the end - a touchingly melancholic celebration of our home. In the week that NASA revealed it has discovered what may turn out to be our sister planet - 600 light years away - and a sci fi film is released about Another Earth, it is a tribute to the power of public broadcasting that a series as powerfully thought-provoking yet visually stunning as this can still be made to highlight the reality that we have only one planet, and we need to start looking after it a lot better, very, very quickly.