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Glossary
Origins of Earth: Magmatic Chaos and the Birth of the Solid World 
Earth's Atmosphere: The Invisible Shield Protecting Life 
The Three Ages of Terrestrial Water: Multiple Origins 
From Carbon 14 to Uranium-Lead: The Science of Dating 
The Boundary of Space: Where Does It Really Begin? 
The Leap Second 
Planetary Alignments: A Fascinating but Relative
Phenomenon 
All Deserts of the World 
Earth's Paleoclimates and Carbon Dioxide 
Three Gorges Dam and Day Length 
International Date Line 
Start Date of the Seasons: A Complex Celestial Mechanism 
Reversal of the Earth's magnetic field over time 
3D Simulator: Revolutions of the Planets 
Geological Time and Mass Extinctions: From the Ordovician to the Cretaceous 
Earth History: Timeline Compressed into 24 Hours 
Earth's Water: An Extraterrestrial Origin? 
Reading the Sky: Understanding Declination and Right
Ascension 
Inversions of the Earth's Magnetic Field 
Earth's Magnetosphere: The Invisible Shield 
Fujita Scale: Classifying the Fury of Tornadoes 
Earth's Radioactivity: The Internal Energy of Our Planet 
The Deep Sea: Exploring the Deepest Ocean Trenches 
Why Are Days Getting Longer? 
The Depths of the Earth: From the Lithosphere to the Core 
Earth's Movements: How Earth Traces Its Spiral Through the Universe? 
How much is the sea level rising? 
The Life of Earth: Structure and Layers of the Earth 
The Eccentricity of Earth's Orbit: An Ellipse That Changes
Everything 
Little Ice Age: The History of a Natural Climatic Cooling 
The Quest for Time: How Ancient Civilizations Used
Astronomy? 
Van Allen Radiation Belt: A Shield Against Cosmic Particles 
Axis of rotation of the planets or obliquity 
The Cosmos in Our Measure: When Man Invents the Universe 
The Galilean Cut 
What is the pendulum fixed relative to? 
Problem of longitude at sea 
World population, still gallopingin 2008 
The Oldest Image of Earth from Space 
Earth's Obliquity and Variations in Its Axis of Rotation 
The Astronomical Unit Fixed: A Length, No Longer an Orbit 
One Molecule, Three States: Solid, Liquid, Gas on a Single Planet 
Simulator, the round of near-Earth cruisers 
Satellites that measure underwater relief 
Hadean's Hell 
The First Free Flight of an Astronaut in Space 
The first measurement of the Earth-Sun
distance 
La The Announced End of the World on December 21, 2012: A Millennial
Prophecy
The Equinoxes: An Astronomical Event
Milankovitch Cycles: The Astronomical Rhythm of Earth's Climate