Aliens are a common element in many works of science fiction. They are typically depicted as more advanced lifeforms from other planets that are either hostile invaders or peaceful visitors exploring Earth. Some key examples include the Cylons from Battlestar Galactica who seek to destroy humanity, and the various alien races Greg encounters through space travel in many Star Trek episodes who have diverse cultures and technologies. Aliens allow science fiction writers to reflect on humanity and ask profound questions by placing people in contact with lifeforms that are both similar and different from us.

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2. Works CitedCylon Centurion. 2007. Photograph. Flickr.com. Yahoo, 17 Mar. 2007. Web. 17 Jan. 2010.Świerczek, Michał. Honorverse Map. 2006. Photograph. Wikipedia. 21 Nov. 2006. Web. 16 Jan. 2010.Williams, Greg. Tractor Beam. 2007. Photograph. Wikipedia. WikiWorld. 12 Dec. 2007. Web. 14 Jan. 2010.Winterling. Picture Frame Gold - Path Included. Photograph. Dreamstime.org. Web. 16 Jan. 2010.

3. Map from the universe of David Weber’s Honor Harrington series

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