NASA’s Kepler space telescope confirmed the existence of 1,284 newfound planets orbiting distant stars, more than doubling the number discovered since the mission was launched in 2009.
A new statistical validation technique enables researchers to quantify the probability that any given candidate signal is in fact caused by a planet, without requiring any follow-up observations. This technique uses two different kinds of simulations-- both simulations of the detailed shapes of transit signals caused by both planets and objects, such as a star, masquerading as planets, and also simulations of how common imposters are expected to be in the Milky Way galaxy. Combining these two different kinds of information gives scientists a reliability score between zero and one for each candidate. Candidates with reliability greater than 99 percent are called “validated planets.”
NASA’s report is from results of a statistical analysis performed on 4,302 potential planets from the Kepler mission’s July 2015 planet candidate catalog. For 1,284 of the candidates, the probability of being a planet was greater than 99 percent – the minimum required to earn the status of “planet.” An additional 1,327 candidates were more likely than not to be actual planets, but did not meet the 99 percent threshold and will require additional study. The remaining 707 candidates were more likely to be some other astrophysical phenomena. This analysis also revalidated 984 candidates that were previously verified by other techniques.
From: The Week magazine, May 27, 2016, Health & Science page, pg. 21.
Further details from: www.nasa.gov/feature/ames/kepler/briefingmaterials160510
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