Are we alone? For decades a global effort has been made to search for extraterrestrial intelligence (SETI), but have we been looking in the wrong place? A new paper suggests that we should be looking for advanced technological civilizations that had access to coal as this was an important energy rich source enabling industrialisation. In this bonus episode, Susie and Rob take a look at the geological, palaeontolological and evolutionary implications of the seach for coal burning aliens.

This week's paper is "How common are oxygenic photosynthesis and large coal deposits on exoplanets?" by Lincoln Taiz and colleagues, published in the International Journal of Astrobiology in January 2026.

Widescreen art by NASA/SETI.