Which planet is referred to as Earth's sister due to its similar size and proximity?

Venus is referred to as Earth's sister planet due to its comparable size and mass. Venus has a diameter of about 12,104 kilometers, which is roughly 95% of Earth's diameter, making it very similar in size. Additionally, both planets are composed primarily of rock and metal, leading to similarities in their geological features.

The proximity of Venus to Earth also contributes to this sister planet designation. Venus is the second planet from the Sun, while Earth is the third, which means they are relatively close neighbors in the solar system. This closeness in size and location often leads scientists to draw parallels between the two planets in terms of their potential to support life and their atmospheric conditions, even though their surface environments are quite different.

Understanding this relationship helps in comparative planetology, where researchers can study these similarities and differences to gain insights into planetary formation and evolution.