What is the primary source of energy for life on Earth?

The primary source of energy for life on Earth is the Sun. Solar energy drives photosynthesis, the process through which plants, algae, and some bacteria convert sunlight into chemical energy stored in glucose. This energy is foundational for nearly all life forms on the planet because it forms the base of the food web; herbivores consume plants, and in turn, carnivores consume those herbivores. Additionally, solar energy influences weather patterns and ecosystems, promoting diverse habitats.

In contrast, while the Earth itself provides the necessary conditions for life, including water and nutrients, it does not serve as an energy source. The Moon and other stars outside of our solar system do not directly contribute energy essential for life on Earth. Thus, the Sun stands out as the universal energy provider critical to sustaining life processes.