Space- physics

    Cards (34)

    • The Milky Way galaxy
    • Eight (plus the dwarf planets)
    • Planets in our solar system orbit around
      • The sun
    • Gravitational force of attraction
    • Phases stars undergo
      • Protostar phase
      • Main sequence phase
    • The sun is a star
    • Phases stars of similar size to the sun go through between being a main sequence star and a black dwarf
      • Red giant
      • White dwarf
    • During fusion processes in a star, all of the naturally occurring elements are produced
    • Stars of a similar magnitude to the sun become a black dwarf at the end of their life-cycle
    • Elements heavier than iron are produced in a supernova
    • Star life-cycle
      1. Protostar phase
      2. Main sequence phase
    • What stars much bigger than the sun can become at the end of their life-cycle
      • Neutron star
      • Black hole
    • Hydrogen nuclei fuse to form heavier elements in a star
    • Phases stars of greater size than the sun go through between being a main sequence star and a neutron star/black hole
      • Red super giant
      • Supernova
    • Very high temperatures are required for fusion reactions to occur in a star
    • Artificial satellites
      • TV satellites
      • Satellites used for satellite imaging
    • For a stable orbit, the radius of orbit must change if the speed changes
      • At higher speeds, the object requires a greater centripetal force
      • For a greater centripetal force, the gravitational force must increase
      • This is achieved by the radius of the orbit being reduced
    • How the force of gravity acting on a satellite affects its speed and velocity
      • The force can alter its velocity since the direction is continually changing
      • It can’t cause a change of speed since there is no force component in the direction of motion
    • Planets and satellites maintain circular orbits because gravity provides the gravitational force that acts as the object’s centripetal force and allows for the object to maintain its circular orbit
    • Type of nuclei
      • Hydrogen nuclei
    • Elements are distributed throughout the universe through the explosion of a massive star (supernova)
    • Type of satellite
      • A natural satellite
    • Red-shift
      An observed increase in the wavelength of light from distant galaxies
    • Red-shift supports the Big Bang theory
    • Compare the observed red-shift of two galaxies, one further away than the other
      • The galaxy that is further away is travelling faster
      • The observed red-shift is greater the further away it is
    • The further away a galaxy is, the greater the observed increase in wavelength
    • Red-shift provides evidence that the universe is expanding
    • The further away a galaxy is, the faster it is moving
    • The Big Bang theory suggests the entire universe started from a very small, hot and dense region in space
    • Scientists observed supernovae to provide evidence that the universe is expanding at an ever faster rate
    • It was thought that gravitational forces would cause this slowing down
    • Prior to observations of supernovae, the rate of expansion was expected to occur at an ever slower rate
    • Ideas explaining the universe’s ever increasing rate of expansion
      • The existence of energy and mass that we can’t detect, known as dark matter and dark energy
      • These ideas are still being developed by scientists and are not yet fully understood
    • Comparison of observed red-shift of two galaxies
      • The galaxy that is further away is travelling faster
      • The observed red-shift is greater the further away it is