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Clicking on the standard buttons below will bring you to resources that will help you breach, answer breaches and independently study all topics in Earth Science.
Most objects in the solar system are in predictable motions.
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Nine planets move around the sun in nearly circular orbits
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Earth’s coordinate system of latitude and longitude, with the equator and prime meridian as reference lines, is based upon Earth’s rotation and our observation of the Sun and stars.
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Earth rotates on an imaginary axis at a rate of 15 degrees per hour. To people on Earth, this turning of the planet makes it seem as though the Sun, the moon, and the stars are moving around Earth once a day. Rotation provides a basis for our system of local time; meridians of longitude are the basis for time zones.
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The Foucault pendulum and the Coriolis effect provide evidence of Earth’s
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Earth’s changing position with regard to the Sun and the moon has noticeable
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Seasonal changes in the apparent positions of constellations provide evidence of Earth’s revolution.
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The Sun’s apparent path through the sky varies with latitude and season.
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Approximately 70 percent of Earth’s surface is covered by a relatively thin layer of water, which responds to the gravitational attraction of the moon and the Sun with a daily cycle of high and low tides.
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The Universe is vast and estimated to be over ten billion years old. The current theory is that the universe was created from an explosion called the Big Bang. Evidence for this theory includes:
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Stars form when gravity causes clouds of molecules to contract until nuclear fusion of light elements into heavier ones occurs. Fusion releases great amounts of energy over millions of years.
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Our solar system formed about five billion years ago from a giant cloud of gas and debris. Gravity caused Earth and the other planets to become layered according to density differences in their materials.
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Asteroids, comets, and meteors are components of our solar system.
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