M2 Lunar tide of the Earth illustrated by the colour shade. The white lines are called co-tidal lines, they meet up at points on the Earth where there is “no tide” or no change in the surface of the ocean due to the M2 tide. The arrows around them show the direction the tide moves about the point (Image credit NASA). Each journey around the sun, a trip of about 940 million kilometers (584 million miles), is called a revolution. A year on Earth is the time it takes to complete one revolution, about 365.25 days. Earth orbits the sun at a speedy rate of about 30 kilometers per second (18.5 miles per second). The Worlds of J. R. R. Tolkien] is beautifully designed and produced . . . It’s a magical book, one is both intricately researched and filled with gems of wonder."—Lorena Carrington, The Bone Lantern

Now let’s focus on why the tide is different on every planet, and there are a lot of reasons; the size, chemical composition, proximity to other stellar objects and many other things are in play to affect the tide on a planet, however here, we will focus on the role of planetary topography; or land and ocean distribution on a planet, and the effect that has on the tide. Over a period of about 10 million years, the dense center of the cloud grew very hot. This massive center became the sun. The rest of the particles and objects continued to revolve around the sun, colliding with each other in clumps. Eventually, these clumps compressed into planets, asteroids, and moons. This process generated a lot of heat. Let’s begin with a question. Are the tides always the same on every planet? Because of the force of gravity, and interaction between planetary bodies, we know every planet will have tides in some form. However, because every planet is different, the tides cannot be the same everywhere. We know from calculations that they are not; the tide is observably unique on every planet in the solar system. Therefore, by that logic, the tide should be different on every planet in the universe.Much like fantasy maps, these maps can be used as a foundation for other things. These maps have since been used to test the state of the tide into the future to understand if the present day does have abnormally strong tides. This marvelous book draws on Garth's substantial research, his perceptive observations about how Tolkien responded to places and changed them for his own purposes, and insights by other Tolkien specialists. Wonderfully supported by a gallery of illustrations, The Worlds of J. R. R. Tolkien is a fine achievement."—Kevin Crossley-Holland, author of The Norse Myths The crust is covered by a series of constantly moving tectonic plates. New crust is created along mid-ocean ridges and rift valleys, where plates pull apart from each other in a process called rifting. Plates slide above and below each other in a process called subduction. They crash against each other in a process called faulting. Earth is an oblate spheroid. This means it is spherical in shape, but not perfectly round. It has a slightly greater radius at the Equator, the imaginary line running horizontally around the middle of the planet. In addition to bulging in the middle, Earth’s poles are slightly flattened. The geoid describes the model shape of Earth, and is used to calculate precise surface locations. Records the default button state of the corresponding category & the status of CCPA. It works only in coordination with the primary cookie.

The charged particles that int eract with Earth’s magnetosphere are called the solar wind. The pressure of the solar wind compresses the magnetosphere on the “dayside” of Earth to about 10 Earth radii. The long tail of the magnetosphere on the “nightside” of Earth stretches to hundreds of Earth radii. The most well-known aspect of the magnetosphere are the charged particles that sometimes interact over its poles—the auroras, or Northern and Southern Lights. The atmosphere has a layered structure. From the ground toward the sky, the layers are the troposphere, stratosphere, mesosphere, thermosphere, and exosphere. Up to 75 percent of the total mass of the atmosphere is in the troposphere, where most weather occurs. The boundaries between the layers are not clearly defined, and change depending on latitude and season. Earth World map Globe Geography, earth, 3D Computer Graphics, world, sphere png 1280x800px 847.91KBEarth’s rotation causes the periods of light and darkness we call day and night. The part of Earth facing the sun is in daylight; the part facing away from the sun is in darkness. If Earth did not rotate, one-half of Earth would always be too hot to support life, and the other half would be frozen. Earth rotates from west to east, so the sun appears to rise in the east and set in the west. One of the most valuable books out there for understanding Tolkien."—David Bratman, Kalimac’s Corner