ziemi

Ziemi (Polish for Earth) is the third planet from the Sun and the only known celestial body to harbor life. In the Solar System, it orbits at an average distance of about 1 astronomical unit (roughly 149.6 million kilometers) and completes one rotation roughly every 24 hours. Its orbital period is about 365.25 days, defining the calendar year. The planet’s diameter is about 12,742 kilometers and its mass around 5.97 × 10^24 kilograms.

Geologically, Ziemi consists of a silicate crust, a viscous mantle, and a metallic core. The crust includes continental and oceanic types, and plate tectonics drive earthquakes and volcanism. The atmosphere is primarily nitrogen and oxygen, with trace gases, supporting weather and climate systems.

Liquid water covers about 71 percent of the surface, forming oceans that regulate climate and sustain life. Landmasses host diverse ecosystems, from forests to deserts and polar regions. The biosphere interacts with the atmosphere, hydrosphere, and geosphere in complex ways.

Humans are a dominant presence, shaping environments, technology, and culture. Ziemi has been observed since ancient times and studied extensively by space missions, satellites, and Earth science research.

It remains the only known world with life, and the study of its systems—astronomical, geological, and biological—continues to inform our understanding of planetary processes and the potential for life elsewhere in the universe.