Researchers suggest at least two Earth-sized planets exist beyond Pluto


There may be at least two undiscovered, Earth-sized planets lurking within our solar system, researchers say in two new papers published in the journal Monthly Notices of the Royal Astronomical Society Letters.
Scientists analyzing a set of "extreme trans-Neptunian objects" found that the elliptical paths of the 13 bodies they analyzed had "unexpected orbital parameters." The team suggests that the discrepancies are the result of "other unknown planets…altering the distribution of the orbital elements." Such unknown planets — dubbed "Planet X" and now "Planet Y" — would most likely exist beyond Neptune and Pluto, Space.com reports.
The latest research follows similar work published in March 2014. Scientists Chadwick Trujillo and Scott Sheppard noted, however, that there could be alternative explanations for the unexpected ETNOs. Lead author of the recent study Carlos de la Fuente Marcos, of the Complutense University of Madrid, agreed that alternate theories must be considered, but that "if (our study) is confirmed, our results may be truly revolutionary for astronomy."
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Sarah Eberspacher is an associate editor at TheWeek.com. She has previously worked as a sports reporter at The Livingston County Daily Press & Argus and The Arizona Republic. She graduated from Northwestern University's Medill School of Journalism.
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