The search for sustainable energy will dominate the twenty-first century. This unit provides an introductory overview of the present energy systems and takes a brief look at where the world may find energy in the future – cleaner use of fossil fuels or renewable energy sources?

The new discipline of astrobiology – that is, the science of searching for extraterrestrial life – is not only rapdly growing, but has also captured the public imagination. This unit examines the emergence of icy satellites of distant planets as potential sites of extraterrestrial life. Focussing on the case study of Jupiter's moon Europa, the unit looks at the potential for life there, and speculates on the ethics of searching for life elsewhere in the solar system.