Lifecycle of Stars (T)

• What is the lifecycle of a star?

  It describes the stages a star goes through from formation to death.
• Why is it important to learn the lifecycle of a star?

  It is important for exams and understanding element formation.
• What is a nebula?

  • A cloud of dust and gas
  • The initial stage of a star's lifecycle
• What causes a nebula to collapse and form a protostar?

  Gravity causes the collapse of the nebula, increasing temperature and forming a protostar.
• What is the temperature of a protostar?

  Millions of degrees Celsius.
• What process occurs when hydrogen nuclei fuse together in a star?

  Nuclear fusion occurs, forming helium nuclei and releasing energy.
• What is a main sequence star?

  • A star that is undergoing nuclear fusion
  • Releases a huge amount of energy
• What happens when the hydrogen in a main sequence star begins to run out?

  The star collapses inward due to the imbalance of forces.
• What is formed when helium nuclei fuse together in a star?

  • Heavier elements
  • The star expands to form a red giant
• What is a red giant?

  A stage in a star's lifecycle where it expands after helium fusion.
• What happens to a red giant when it stops fusing helium?

  It shrinks and forms a white dwarf.
• What is a black dwarf?

  A white dwarf that has cooled down and stopped releasing energy.
• How does the lifecycle of a star much larger than the Sun differ?

  • Expands into a red supergiant
  • Heavier elements are formed through fusion
• What is the significance of a supernova in the lifecycle of a star?

  It produces elements heavier than iron and distributes them in the universe.
• What are the two possible remnants of a star after a supernova?

  A neutron star or a black hole.
• What is a neutron star?

  • A remnant of a supernova
  • Consists of densely packed neutrons
• What is a black hole?

  • A remnant of a supernova
  • Has such strong gravity that not even light can escape