The shortlist exhibition for the Artes Mundi prize has just opened in Cardiff, Wales. The prize, which is now in its eighth edition, celebrates artists who tackle “the biggest issues facing our world, from near constant surveillance and entrenched racism, to industrial exploitation on a global scale and state control of individual freedoms”. This image is by Trevor Paglen, one of five shortlisted artists, who was recently the topic of conversation after announcing plans to send an artwork called The Orbital Reflector into space with Elon Musk’s SpaceX.