Earth. Characteristics and simulations
The online simulations of the Earth on this page will allow you to deepen your knowledge of our planet. We will discover its most outstanding features, its shape and size, its composition and its most outstanding motions
This Thematic Unit is part of our Earth Sciences collection
STEM OnLine mini dictionary
Core
Center of the Earth, made of iron and nickel, divided into outer and inner.
Earth
Third planet from the Solar System, the only one with confirmed life and surface liquid water.
Earth’s Crust
Outermost and thinnest layer of the Earth, composed of solid rocks.
Geoid
Theoretical shape of the Earth equivalent to the mean sea level extended through the continents.
Lunar Eclipse
Event where the Earth comes between the Sun and the Moon, casting its shadow on it.
Mantle
Intermediate layer of the Earth located between the crust and the core.
Nutation
Small periodic oscillation of the Earth’s axis combined with precession.
Penumbra
Region of partial shadow surrounding the umbra during an eclipse.
Precession
Slow and gradual change in the orientation of Earth’s rotational axis.
Rotation
Earth’s movement on its own axis that results in day and night.
Translation
Earth’s movement around the Sun that determines the length of the year.
Umbra
Darkest and central part of the shadow cast during an eclipse.
What is the Earth
Earth is our home, a beautiful and diverse planet. It is the third planet from the Sun in our solar system and is composed of a unique combination of elements and conditions that allow the existence of life as we know it.
Characteristics of the Earth
It is the densest and fifth largest of the eight planets in the solar system. It is also the largest of the four terrestrial or rocky planets. Earth is home to an astonishing diversity of ecosystems and living things, from microorganisms to animals and plants. In addition to terrestrial life, the oceans are home to a variety of marine creatures, from tiny fish to majestic whales and fascinating coral reefs.
Shape and size of the Earth
The shape of the Earth is described as a geoid, meaning that it has a shape similar to a sphere that is slightly flattened at the poles and widened at the equator. This is due to the effect of the Earth’s rotation, which generates a slight bulge at the equator due to centrifugal force. The equatorial radius is 6,378 kilometers (3,963 miles) while the polar radius is 6,357 kilometers (3,950 miles).
Composition of the Earth
The Earth’s surface is mostly (71%) covered by oceans of water. The remainder is made up of continents and islands. The Earth’s poles are mostly covered with solid ice. No other planet is known with this amount of liquid water, which is indispensable for any known type of life. The interior of the planet is geologically active, with a thick layer of relatively solid mantle, a liquid outer core that generates a magnetic field, and a solid inner core composed of about 88 % iron. The Earth is covered by a layer of air called the atmosphere, which protects and maintains conditions suitable for life. This atmosphere is composed mainly of nitrogen and oxygen.
Motions of the Earth
The Earth performs several motions, the most important of which are rotation and translation.
Rotational motion
The Earth rotates on its imaginary axis in a west-to-east motion. This complete rotational motion is carried out in approximately 24 hours, resulting in the succession of days and nights. The Earth’s rotation is responsible for the daily cycle of the sun and for the patterns of light and dark in different regions of the planet.
Translational motion
The Earth performs a translational motion around the Sun. It takes approximately 365.25 days (one year) to complete one orbit around the Sun. This translational motion is responsible for the seasons of the year. As the Earth moves around the Sun.
Other motions of the Earth
Other motions of the Earth are precession, nutation, Chandler’s wobble and perihelion precession.
These online simulations of the Earth help to improve our knowledge about our home in the universe – make the most of them!
STEM OnLine mini dictionary
Core
Center of the Earth, made of iron and nickel, divided into outer and inner.
Earth
Third planet from the Solar System, the only one with confirmed life and surface liquid water.
Earth’s Crust
Outermost and thinnest layer of the Earth, composed of solid rocks.
Geoid
Theoretical shape of the Earth equivalent to the mean sea level extended through the continents.
Lunar Eclipse
Event where the Earth comes between the Sun and the Moon, casting its shadow on it.
Mantle
Intermediate layer of the Earth located between the crust and the core.
Nutation
Small periodic oscillation of the Earth’s axis combined with precession.
Penumbra
Region of partial shadow surrounding the umbra during an eclipse.
Precession
Slow and gradual change in the orientation of Earth’s rotational axis.
Rotation
Earth’s movement on its own axis that results in day and night.
Translation
Earth’s movement around the Sun that determines the length of the year.
Umbra
Darkest and central part of the shadow cast during an eclipse.
Explore the exciting STEM world with our free, online, simulations and accompanying companion courses! With them you’ll be able to experience and learn hands-on. Take this opportunity to immerse yourself in virtual experiences while advancing your education – awaken your scientific curiosity and discover all that the STEM world has to offer!
Simulations of the Earth
Calculating the circumference of the Earth by Eratosthenes
The first person to measure the size of the Earth was Eratosthenes, an ancient Greek scientist about 2,000 years ago. From basic geometry and the shadow of a tower he calculated the circumference of the Earth to be about 46,000 km. This value is slightly larger than the value measured today of about 40,000 km.
Giants of science
“If I have seen further, it is by standing on the shoulders of giants”
Isaac Newton
Isaac Newton
–
Nicolaus Copernicus
–
Become a giant
The Radio Sky II: Observational Radio Astronomy
The Radio Sky I: Science and Observations
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The History of Ancient Environments, Climate, and Life
Sensing Planet Earth – Water and Ice
Our Global Ocean – An Introduction Course
Sensing Planet Earth – From Core to Outer Space
Professional development for Educators
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Giants of science
“If I have seen further, it is by standing on the shoulders of giants”
Isaac Newton
Galileo Galilei
–
Tycho Brahe
–
Become a giant
The Radio Sky II: Observational Radio Astronomy
The Radio Sky I: Science and Observations
Our Place in the Universe
Our Global Ocean – An Introduction Course
Sensing Planet Earth – From Core to Outer Space
Sensing Planet Earth – Water and Ice
The History of Ancient Environments, Climate, and Life
Professional development for Educators
Introduction to Online Education & Course Planning
Teach kids computing: Computing systems and networks
Teach teens computing: Functions and algorithms, searching and sorting in Python
Teach teens computing: Machine learning and AI
Test your knowledge
What is the Earth and what are its main characteristics?
What are the movements of the Earth and how do they affect daily life?
How is it that we don’t feel the Earth spinning even though we have day and night every day?
Why do the seasons change if the distance to the Sun doesn’t vary much?
Does it make sense that the Earth has more movements besides rotation and revolution?
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