Sun

• 6000°K (6273°C)
• Fusion Reactor
  • 4 ¹H --> ⁴He + 2e^- + energy
• Solar Constant = amount of Sun's energy intercepted by the Earth
  • Avg. 2 cal / cm² minute

Mercury

• 430°C
• lacks an atmosphere

Venus - sister planet

• 450°C
• massive cloud cover
  • 96.4% CO₂
  • 3.4% N₂

Earth

• 15°C
  • 78% N₂
  • 21% O₂
• Water

     0°C     100°C
  ice | liquid | gas