What Guy Fawkes can teach us about the sky at night

With bonfire night on the horizon, scientists reveal just why fireworks are differently coloured and what this can teach us about stars in space. Elements commonly found in salts are used to make the colours in fireworks. The colours are caused when the elements are heated, causing them to release light in different colours, from bright blues to deep reds. Scientists use these chemistry phenomena when making multicoloured fireworks and harness them to investigate stars in the night sky. Alex Baker, Assistant Professor, Department of Chemistry, University of Warwick, said: "Fireworks are made of different chemical elements - including potassium and sodium. The atoms of these elements house even smaller, negatively charged electrons. "When these elements are heated, such as by someone lighting a firework with a flame, the electrons become 'excited'.