Final answer:
Earth is unique due to its life-sustaining greenhouse effect, an extremely large moon, and the presence of surface liquid water essential for life, contributing to its robust and detectable biosphere.
Step-by-step explanation:
Earth is unique in our solar system for several reasons. It has a life-sustaining greenhouse effect that helps maintain temperatures suitable for the existence of life. Unlike any other terrestrial planet, Earth is accompanied by an extremely large moon, which influences various Earth processes, such as its climatic stability. Most notably, Earth has liquid water on its surface, which is essential for life as we know it and contributes to Earth being known as the "Blue Planet". This abundance of water, combined with a habitable temperature range and a photosynthetic biosphere, indicates that Earth maintains a robust biosphere capable of creating planet-scale changes that are detectable from space, making it an exceptional case in the solar system.