Suppose the distance between earth and sun becomes half of its present distance. What is likely to happen to life?

Even when Earth is present at a sufficient distance from the Sun, the temperature on the surface of the Earth is too high. If the distance between the Sun and the Earth becomes half of the existing distance then the temperature on the Earth would be enormous for us to bear. It would even destroy the vegetation on the Earth. The water may dry up too soon. Seeing these conditions we can definitely say that if the distance between the Earth and the Sun is halved then there would be no life on the Earth.