Astrophysics

• What does the solar system include?

  Sun, 8 planets, dwarf planets, moons
• Why do objects in the solar system orbit?

  Due to gravitational attraction
• What type of satellites orbit planets?

  Artificial satellites
• What keeps objects in orbit?

  Balance between gravity and inertia
• What is the orbital speed equation?

  v = $\frac{2\pi r}{T}$
• What does 'v' represent in the orbital speed equation?

  Orbital speed
• What does 'r' represent in the orbital speed equation?

  Radius of orbit
• What does 'T' represent in the orbital speed equation?

  Time for one orbit (period)
• How does the distance of an orbit affect its speed?

  Closer orbits have higher speeds
• Where do stars form?

  In nebulae
• What is the first stage of a low-mass star's life cycle?

  Protostar
• What is the stable phase of a low-mass star?

  Main Sequence Star
• What follows the Main Sequence Star stage in a low-mass star's life cycle?

  Red Giant
• What is the final stage of a low-mass star's life cycle?

  Black Dwarf (eventually)
• What is the first stage of a high-mass star's life cycle?

  Protostar
• What follows the Main Sequence Star stage in a high-mass star's life cycle?

  Red Supergiant
• What happens after a high-mass star becomes a Red Supergiant?

  It undergoes a Supernova
• What can result from a Supernova in a high-mass star?

  Neutron Star or Black Hole
• What does red-shift indicate about distant galaxies?

  They are moving away
• What does a greater red-shift imply about a galaxy?

  It is moving faster
• What does red-shift provide evidence for?

  Expansion of the universe
• What does the Big Bang Theory suggest about the universe's origin?

  It began from a small, hot point
• How long ago did the Big Bang occur?

  ~13.8 billion years ago
• What supports the Big Bang Theory?

  Red-shift and Cosmic Microwave Background Radiation
• What is Cosmic Microwave Background Radiation (CMBR)?

  Leftover radiation from the Big Bang
• What do all objects with mass have?

  A gravitational field
• What does the strength of a gravitational field depend on?

  Mass and distance from the object
• What is the formula for weight?

  W = $m \times g$
• What does 'W' represent in the weight formula?

  Weight (N)
• What does 'm' represent in the weight formula?

  Mass (kg)
• What does 'g' represent in the weight formula?

  Gravitational field strength (N/kg)
• What are geostationary satellites used for?

  Communications
• What characterizes low polar orbits?

  They orbit quickly over the poles
• What are low polar orbits used for?

  Imaging and weather
• What are the possible fates of the universe?

  • Keep expanding forever
  • Slow down and stop
  • Collapse back in (Big Crunch)
• What factors determine the fate of the universe?

  • Amount of mass
  • Amount of dark energy