ASTR 1110 book summary - ch.1.3

ASTR 1110 book summary - ch.1.3 - with respect to a line...

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Astronomy – Book Notes 1.3 Spaceship Earth Most basic motions of Earth – its: o Rotation (spin) about its axis – more than 1,000 kilometers/hr (600 mph) o Orbit (sometimes called revolution ) around the Sun. As the earth is rotating about its axis, it is also orbiting the Sun, completing one orbit each year. o Astronomical Unit (AU): Earth’s average orbital distance - the average distance (semimajor axis) of the Earth from the Sun, which is about 150 million km. (93 million miles) o Ecliptic Plane : The plane of the Earth’s orbit around the Sun. o Axis Tilt (of a planet in our solar system): The amount by which a planet’s axis is tilted
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Unformatted text preview: with respect to a line perpendicular to the ecliptic plane. Oriented so that it points almost directly at a star called Polaris ( North Star ) Earth orbits the un in the same direction that it rotates on its axis: counterclockwise as viewed from above the North Pole. Our Local Solar Neighborhood o Local Solar Neighborhood: The portion of the Milky Way Galaxy that is located relatively close (within a few hundred to a couple thousand light-years) to our Sun. Even smaller region of the Galaxy...
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This note was uploaded on 02/27/2008 for the course ASTR 1110 taught by Professor Hornstein during the Spring '08 term at Colorado.

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