Spheres of Earth

The 17 Spheres of Earth

How many spheres of Earth exist on Earth? If you count them all, you would get about 17 of them. This is the definitive guide to all 17 spheres of Earth.

Geographic Poles

Where is the North and South Pole?

If you stick a pencil through Earth at the point of rotation, these 2 points are the north/south poles. Geographically, it’s where longitude lines converge.


A Guide to Earth’s Lithosphere

Earth scientists compare the lithosphere to a thin, solid and brittle eggshell encasing our inner planet or a thick piece of wood that dries and breaks.


How To Define the Geosphere

It’s difficult to pinpoint an exact definition for the “geosphere” because it’s used in several different ways. But here are 2 ways to define the geosphere.

How Gravity Works

How Gravity Sculpted the Earth

What brings order on Earth is gravity. For all matter, it’s always at work. This is how gravity works for ocean tides, planet formation and escape velocity.

Earth Age

Earth Age: How Old Is the Earth?

By dating meteorites, we find the oldest rocks are 4.5 billion or so years old. Thus, we conclude the same staggering 4,543,000,000 years for Earth’s age.

Earth tilt

Earth Tilt: 23.5 Degrees Axis

Imagine sticking a pencil into the Earth’s poles and twisting your wrist 23.5°. This is the Earth tilt essential in seasonal patterns, climate and life on Earth.

Ocean Wave Reverberation

Why Does the Earth Hum?

Seismometers always record periodic noise. Once mysterious in nature, we attribute Earth hum to ocean waves crashing into continents, vibrating like a bell.

Earth Shape Oblate Spheroid

Shape of the Earth: The Oblate Spheroid

Earth is not a perfect sphere. In fact, it’s in the shape of an oblate spheroid. Earth shape bulges at the equator and flattens at the north and south pole.