Lec #1 The Seasons

Lec #1 The Seasons - Tuesday, May-10-11 Lec #1: The Seasons...

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Tuesday, May-10-11 Lec #1: The Seasons The ecliptic plane is the plane of the Earth’s orbit around the sun. The only 2 objects that lie in it are the Earth and Sun. Pole B is the North Pole. If something is not spinning then there is no defined pole. The North Pole is looked down towards it and is spinning in a counter-clockwise direction. Babylonians created a degree system with a full circle including 360 degrees of rotation. Subtends means to stretch out. A degree is divided into 60 minutes of arc or arcminutes. Therefore there are 3600 arcseconds in one degree. The moon and the sun subtend an angle of slightly greater than ½ degree with 32 arcminutes. The angular distance between the distance of your thumb and pinkie it is 20 degrees. The Big Dipper is part of a large constellation is a little over 5 degrees. Orion’s belt subtends an angle of a little less than 3 degrees. You can’t see anything smaller than 3 arcminutes. These two stars point to the North Star. Latitude is the angular distance north or south of the equator. The arctic circle is a small circle however the centre of it does not coincide with the centre of the Earth. The latitude of any place on the equator is 0 degrees. There are infinitely many place on Earth with the same latitude. Longitude is the angular distance East or West or any great circle that passes through the north/south

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This note was uploaded on 07/20/2011 for the course PHYS 1510 taught by Professor Dawson during the Summer '11 term at Trent University.

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Lec #1 The Seasons - Tuesday, May-10-11 Lec #1: The Seasons...

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