The Earth's Spheres by

Main Ideas

bl0425033 — 2025-10-10 01:57:00 UTC

The Earth is made up of four main spheres: lithosphere, hydrosphere, biosphere, and atmosphere. These spheres make up a system that keeps everything on Earth going.

The Lithosphere

bl0425033 — 2025-10-10 02:04:13 UTC

- This layer is sometimes called the geosphere. This is because it is made up of all the rocks on the Earth including the mantle and crust.

- The thickness of the lithosphere is 40 km to 280 km

- The lithosphere is made of lose to 12 major tectonic plates and multiple minor plates

The Hydrosphere

bl0425033 — 2025-10-10 02:08:03 UTC

- The hydrosphere is made up of all the water on or near the Earth's surface. This includes all bodies of water and the moisture in the air.

- The Earth's water is not static. It moves constantly through the hydrological cycle.

The Biosphere

bl0425033 — 2025-10-10 02:11:25 UTC

- The biosphere is made up of all living organisms on the Earth.

- It is made up of several biomes where similar animals live and thrive in an environment best for them.

The Atmosphere

bl0425033 — 2025-10-10 02:15:27 UTC

- The atmosphere is all of the gasses that surrounds our planet. They are held in place by the Earth's gravity.

- The air of our planet is 79% nitrogen and about 21% oxygen, the rest is other small amounts of different gasses.

- The atmosphere is about 10,000 kilometers high and is divided into four zones. The four zones are the troposphere, stratosphere, mesosphere, and the thermosphere.