Youtor
Teach Astronomy Perihelion and Aphelion
>> YOUR LINK HERE: ___ http://youtube.com/watch?v=wwYcuc6wVrU
http://www.teachastronomy.com/ • Two important points in any elliptical orbit in the solar system or beyond are perihelion and aphelion. They come from the Greek roots peri meaning close, ap meaning far, helion related to Helios, the word for the Sun. Perihelion is the closest approach of an object to the Sun, and aphelion is its most distant place. The planets in the solar system have perihelions and aphelions that are close to each other because their orbits are slightly elliptical. In the case of a comet, perihelion is a much smaller distance than aphelion, and a comet is most active when it is closest to the Sun.
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