Science PAT

• Hazards of space


  • Microgravity
  • Weightlessness
  • Bone density
  • Muscle atrophy
  • Coordination concerns
  • Temperature concerns
• Microgravity


  Humans experience weightlessness due to "freefall"
• Causes of issues in space

  • Bone density
  • Muscle atrophy
  • Coordination concerns
  • Temperature concerns
• With temperature, atmosphere temperatures go extremely hot and very cold
• Survivable features are not seroprotection for humans
• Protection levels are not equal
• Unprotected human cells expand/burst, gases and body fluids are released (boiling fluids)
• Food must be made, grown, or transported, and all food must be recycled
• Water must be recycled
• Radiation is DIFFICULT and EXPENSIVE to protect against in space
• Cosmic rays contain different forms of radiation with little to no protection
• Radiation affects cells in the body, causing cancer and cardiovascular disease
• If space junk hits a spacecraft or active satellites, it is damaging and dangerous
• Galileo's early drawings showed shadows on the moon, suggesting mountains and craters
• Galileo recorded how sunspots on the sun change over time, suggesting the sun rotates on its own axis
• Galileo's tracking of the moons of Jupiter showed they appeared to be revolving around the planet, disproving the geocentric theory
• Galileo recorded stars as pinpoints
• Objective lens


  Where light enters the telescope (large lens in front)
• Focal length


  Distance from the lens to the place where the light beams converge (focus)
• Ocular lens


  Where the magnified light leaves the telescope to enter the eye
• Magnification


  Makes something look bigger but doesn't necessarily enhance the detail of the image
• Resolving power


  The ability to distinguish one point from another - higher resolving power means more detail can be seen
• Increasing the objective diameter increases the resolving power of the telescope
• Refraction


  The bending of light rays, and lenses bend light
• Refracting telescopes


  Use lenses to refract light
• Convex lenses


  Curved outward, make things look bigger but blurry
• Concave lenses


  Curved inward, make things look smaller but clearer
• Reflecting telescopes


  Use mirrors to reflect light instead of bending it, so there is no colour distortion
• Combination telescopes


  Use both mirrors and lenses
• Radio telescopes


  Use longer wavelength radio waves which can penetrate dust and clouds better than light waves, but result in lower resolution images
• Altitude


  The angle the object makes with the horizon or the distance it appears above the horizon
• Azimuth


  The object's cardinal direction such as north, east, south, or west, or number of degrees the object is rotated clockwise from a fixed reference point (north)
• Parallax


  The apparent shift in the position of an object due to the location of the observer
• Astronomical unit (AU)


  The distance from the Earth to the Sun
• Light year


  The distance light travels in one year
• Types of spectra


  • Absorption (dark lines)
  • Emission (bright lines)
  • Continuous (coloured)
• Doppler effect


  The change in wavelength of sound or light emitted by an object due to its motion relative to the observer
• Artificial satellite


  A man-made object intentionally placed in orbit around a planet or moon
• Natural satellite


  A celestial body that orbits a larger celestial body
• Gravity


  A force that pulls objects towards each other, the magnitude depends on the size of the objects and their proximity