NASA stoked curiosity for a few hours on a discovery made with the Kepler telescope which works by photometry (ie the use of light radiation as the human eye can perceive it). Following the conference on May 10 at 7 p.m. (French time), the news finally broke: Kepler discovered no less than 1284 new exoplanets. “This announcement more than doubles the number of such planets discovered outside our solar system by Kepler. This gives us hope that somewhere around a star similar to our sun, we will eventually discover a sister planet to Earth,” said Ellen Stofan, NASA chief scientist. This discovery is also the most enormous discovery of planets that has ever been made.
Of the 5000 potential planets found so far 3200 have now been verified and it should be noted that 2325 of these planets had been discovered by Kepler. Launched in 2009, Kepler is the first mission to find planets similar in size to Earth that can support life.
Then, it was with a catalog of 4302 potential planets that the analysis was made by the Kepler space telescope in July 2015. For 1284 of these planets, the specialists had serious doubts due to the 99% probability that they may have characteristics allowing them to be effectively considered as planets. And for the time being 1327 additional planets are more likely to be planets than not (but the probabilities do not reach 99% like the others, they will have to be studied in more detail to have confirmation of their status ). The last 707 candidates are probably rather other varied astronomical phenomena. In addition, the analysis provided by Kepler also validated 984 potential planets that had already been identified by other means. In the last planets that have been validated, because of their size, 550 could be rocky planets like our own planet.
Paul Hertz, the director of the Astrophysics Division of NASA headquarters did not fail to note that before “it was not known whether exoplanets were rare or common in the galaxy. Thanks to Kepler and the research community, we now know that there could be more planets than stars. This discovery informs future missions that will be needed to bring us ever closer to the answer of whether we are alone in the universe. »
Kepler focuses on the distinct signals from the planets. Much like the transit of Mercury in front of the Sun on May 9, he observes what happens when the planets pass in front of, or transit in front of, their star. However, as we know since the discovery of the first planets outside our solar system more than two decades ago, researchers have embarked on a laborious process of verifying each planet one by one. Nevertheless, this is a method of statistical analysis that can be applied to several planets simultaneously. Timothy Morton, a scientist from Princeton University who was associated with this research, compared this phenomenon to bread crumbs: “If you throw a few big crumbs on the ground, you can pick them up one after another. But if you spill an entire bag of tiny crumbs, you’ll need a broom. This statistical analysis is our broom. »