All the Earth's heat and light comes from the Sun. The Sun keeps the temperature on the Earth at -50°C to +50 °C.

Most living things can only survive at 2°C to 50°C. If the Earth received less heat from the Sun, the oceans would turn to ice and life would die. If the Earth received more heat from the Sun, the oceans would boil and life would die.

We are very lucky, we receive that much heat from the Sun that we need.

• What is the temperature at your place right now?
• Do you have a thermometer?
• How can you check the temperature online?