sentence: Heavy elements are needed to make living things.
sentences_before: Without supernovas there would be no life on Earth. This is because many of the chemical elements were made in supernova explosions.
sentences_after: The supernova is the only way heavy elements can be made. Other elements were made by fusion in stars. Heavy elements need very high temperature and pressure to form. In a macho supernova explosion the temperature and pressure are so high that heavy elements can be made. Scientists call this 'supernova nucleosynthesis'.
concept_name: heavy element
headings: Supernova Supernovas and life