We can look to the future using a solid understanding of how the climate of the Earth has varied in the past. In this way, predictions can be made. ‘Ultimate climate change’ predicts the future of the Earth's climate and the Earth itself. While multi-cellular life on Earth is likely to end in about a billion years and microbes in about 3 billion years, this does not mean the end of the Earth. The Earth is predicted to end in about 5 billion years' time. The sun is about halfway through turning its hydrogen into helium.