Sunsets on Tatooine

vlcsnap-2014-06-13-14h33m51s902“If the stars should appear one night in a thousand years, how would men believe and adore, and preserve for many generations the remembrance of the city of God?” ~ Ralph Waldo Emerson

Yesterday, astronomers at NASA’s Jet Propulsion Laboratory in California made an interesting discovery. While studying an exoplanet in a triple-star system, they discovered that one of the stars in the system was itself a binary-star system, meaning that the exoplanet in question was actually being reared by four different stars. This is not the first such discovery (citizen scientists spotted the same phenomenon back in 2012), but scientists can now infer that approximately 4% of all “solar-type stars” are engaged in quadruple-star systems. To learn more, check out the links here, here, and here. To understand the schematics of how a single planet can have multiple “suns” in its sky, check out this helpful diagram. Meanwhile, it is worth noting that this otherwise obscure fact about stellar evolution, that planets can exist in multiple-star systems, has been utilized to great effect by storytellers on at least two famous occasions. First, fans of Star Wars will no doubt recognize that the image in the overhead banner depicts the famed dual sunset on Tatooine, but only true fans will¬† know that this scene shows Uncle Owen, Aunt Beru, and infant Luke Skywalker at the end of Episode 3, an effective prelude to the far more iconic shot of restless Luke watching the dual sunset near the beginning of Episode 4. Second, since the unique configuration of this four-star system means that the exoplanet only experiences true darkness once every few thousand years, I was reminded of Isaac Asimov’s classic short story, “Nightfall.” In 1941, Asimov’s editor provided him with the quote from Emerson that headlines this essay (see above). In response, Asimov wrote what is routinely named the greatest science fiction short story of all time. If you’d like to judge for yourself, you can read the full text of Asimov’s classic at this link.