Earth in Science Fiction - Common Themes

Common Themes

• Earth is often depicted as a member of an interstellar community. Earth is often depicted as a major power-broker in the community due to anthropocentrism. Perhaps the most notable example of this is Star Trek (where Earth is the capital of the United Federation of Planets). Earth can also be depicted as the head of an empire as in Poul Anderson's Dominic Flandry series where "The barbarians in the long ships waited at the edge of the Galaxy for the ancient Terran Empire to fall ... The brilliant Starship Commander Flandry fought to save the empire even as he scorned it" (from the preface to The Rebel Worlds). Marion Zimmer Bradley's Darkover series, too, has a brooding Terran Empire maintaining a colonial enclave on the planet Darkover where the plot takes place, and on countless others. Haegemonia: Legions of Iron also features an empire controlled from Earth with other major planets, such as Eden IV. In the BBC science fiction show Doctor Who, many episodes set in the future depict earth as being the head of an empire that stretches across many galaxies.
• Earth can also play host to alien invasion. While reasons vary, in most stories, it is because extraterrestrials are looking for a new world to colonize or otherwise dominate. The aliens are often used to portray nearly all-powerful beings, placing the strongest forces on earth at the receiving end of attacks that they can barely understand. This theme is one of the earliest in science fiction, demonstrated by H. G. Wells in The War of the Worlds and Doctor Who, where the invasions in the 1960s, 1970s and the 1980s are small scale, and the invasions after the year 2000 are large scale, and also such works as Independence Day. In such scenarios, the author often uses deus ex machina to allow the invasion to be repulsed. In others, like Footfall and Worldwar, the author depicts aliens only slightly more advanced than the inhabitants of Earth, and are fought to a stand-still or defeated in battle. The opposite has also been depicted, with Earth becoming a refuge to aliens as seen in the Men in Black series of movies, and Alien Nation series.
• The memory of Earth and its location may be lost to the sands of time or shrouded in myth. Isaac Asimov's Foundation and Empire series depict a common theme of a destroyed Earth. In other works, such as Battlestar Galactica, it is largely forgotten except by the religious. In the numerous books of the Dumarest saga by E.C. Tubb, the adventurer protagonist was born on a "galactic backwater" Earth and at a young age had stowed away on a rare spaceship touching down on the planet; having seen more than enough of the galaxy he wants to go back, but no one else had ever heard of the planet. The first Terran inhabitants of the Koprulu Sector are Earth-born criminals in sleeper ships in StarCraft. The expansion also mentions about Earth: upon hearing of the United Earth Directorate's forces' arrival, Zeratul remarks "Raynor spoke me of the distant Terran homeworld of Earth." This implies that the Terrans still know about Earth but its location is lost (StarCraft manual mentions that the sleeper ships have became lost in hyperspace when an error erased the intended destination's coordinates, as well as those of Earth's, resulting in the ships going at full speed for several decades until the engines broke down). Also, the Terran Confederacy uses the same flag as the Confederacy in the American Civil War.
• Earth could have been completely destroyed or rendered uninhabitable, but its location (or at least its former location) is well-known. This last scenario is also popular, and was featured in the movie Titan A.E., as well as in The Hitchhiker's Guide to the Galaxy.
• Some works, such as Star Wars series and many fantasy works, never mention the Earth at all (although a proposed novel, Robert J. Sawyer's Alien Exodus, would have linked Earth to the Star Wars universe). This allows the author to operate in a realm unfamiliar and otherworldly to the reader or to explore contentious issues and historical themes in an otherwise entirely alien environment, giving the work a radically different perspective. In the Homeworld games for example, Earth's existence is unknown - and indeed entirely immaterial - as the games take place in a different galaxy altogether (specifically the Whirlpool Galaxy). However, judging by the appearance of members of the Kushan/Hiigaran people, most notably Karan S'jet, Hiigaran biology is at least outwardly similar, if not identical, to human biology.