The sun: provides heat and light needed to support life.
Magnetic field: deflects the solar wind.
Ozone layer: Acts as a barrier against ultraviolet light and other radiation.
Greenhouse gases such as methane and carbon dioxide: retain warmth within the Earth.
Oxygen and carbon dioxide: oxygen is needed for aerobic respiration.
carbon dioxide is needed by photosynthesising organisms.
Liquid water: has many useful properties such as good solubility properties.
