P1 Key Word

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Across
  1. 1. FUSION The process in which two small nuclei combine to form a larger one, releasing energy (e.g. hydrogen combining to form helium). This happens in stars, including the Sun
  2. 4. Lump of rock and ice in a highly elongated orbit around the Sun
  3. 7. The tiny central part of an atom (made up of protons and neutrons).
  4. 9. The maximum disturbance of a wave motion from its undisturbed position
  5. 10. The layer of rock between the crust and the outer core of the Earth (approximately 2900 km thick)
  6. 11. theoretical beginning of the Universe, when energy and matter expanded outwards from a point
  7. 13. A collection of thousands of millions of stars held together by gravity
  8. 14. WAVE A wave in which the particles of the medium vibrate in the same direction as the wave is travelling. Sound is an example
  9. 16. The distance between one wave crest (or wave trough) and the next
  10. 17. The number of waves passing a set point, or emitted by a source, per second
  11. 18. A dwarf rocky planet, generally orbiting the Sun between the orbits of Mars and Jupiter.
  12. 20. Event in which rocks break to allow tectonic plate movement, causing the ground to shake
  13. 22. SPEED The speed at which waves move through a medium
  14. 23. RIDGE A line of underwater mountains in an ocean, where new seafloor constantly forms
  15. 25. Longitudinal shock waves following an earthquake that can travel through the molten core of the Earth; they change direction at the boundary between different layers of the Earth
  16. 27. The movement of solids at the Earth’s surface (for example, soil, mud, and rock) caused by wind, water, ice, gravity, and living organisms
Down
  1. 2. The centre of the Earth. It’s made mostly from iron, solid at the centre and liquid above.
  2. 3. The shift of lines in a spectrum towards the red (longer wavelength) end, due to the motion of the source away from us
  3. 4. The movement that occurs when hot material rises and cooler material sinks.
  4. 5. Molten (liquid) rock
  5. 6. Scientist who studies rocks and the changes in the Earth
  6. 8. Angle between two imaginary lines from two different observation points on Earth to an object such as a star or plant, used to measure the distance to that object
  7. 12. DRIFT: Slow movement of continents (land masses) relative to each other
  8. 15. Spherical object orbiting the Sun, smaller than a planet and larger than an asteroid
  9. 19. Faint patch of light in the night sky. With good telescopes we can see that some are gas clouds, others are distant clusters of stars.
  10. 21. BRIGHTNESS: The apparent brightness of a star as seen from Earth; a dim star close to Earth may appear brighter than a bright one that is further away
  11. 22. EQUATION The speed of a wave is equal to its frequency multiplied by its wavelength
  12. 24. A rocky layer at the surface of the Earth, 10 – 40 km deep
  13. 26. CYCLE Continuing changes in rock material, caused by processes such as erosion, sedimentation, compression, and heating
  14. 28. BRIGHTNESS: A measure of the light emitted by a star compared to the Sun, taking into account how far away it is