![]() These signals are extremely difficult to find. Roughly one out of every million stars in our Galaxy is visibly affected by microlensing at any given time, but only a few percent of these are expected to be caused by planets. This produces a short burst in brightness that can last from hours to a few days. ![]() Predicted by Albert Einstein 85 years ago as a consequence of his General Theory of Relativity, microlensing describes how the light from a background star can be temporarily magnified by the presence of other stars in the foreground. Such planets may perhaps have originally formed around a host star before being ejected by the gravitational tug of other, heavier planets in the system. These new events do not show an accompanying longer signal that might be expected from a host star, suggesting that these new events may be free-floating planets. However, the four shortest events are new discoveries that are consistent with planets of similar masses to Earth. Many of these had been previously seen in data obtained simultaneously from the ground. The study team found 27 short-duration candidate microlensing signals that varied over timescales of between an hour and 10 days. The study, led by Dr Iain McDonald of The University of Manchester, UK, (now based at the, UK) used data obtained in 2016 during the K2 mission phase of NASA’s Kepler Space Telescope.ĭuring this two-month campaign, Kepler monitored a crowded field of millions of stars near the centre of our Galaxy every 30 minutes in order to find rare gravitational microlensing events. The results include four new discoveries that are consistent with planets of similar masses to Earth, published today in Monthly Notices of the Royal Astronomical Society. The Kepler mission has cost NASA about $600 million, and the US space agency said in 2013 that two of its orientation wheels had lost function, leaving the space telescope beyond repair.īut scientists have years to pore over the data it has returned in order to narrow the search for Earth-like worlds.Tantalising evidence has been uncovered for a mysterious population of ’free-floating’ planets which may be alone in deep space, unbound to any host star. Other scientific tools are needed to judge whether the planet is gassy or rocky. Kepler identifies possible planets by watching for dips in the brightness of stars, which could be caused by a planet passing between the star and the telescope. Of those 12 new candidates, Kepler 452b "is the first to be confirmed as a planet," NASA said. The new catalog includes 12 candidates that are less than twice the diameter of Earth and which are orbiting in the habitable zones of their stars. "This catalog contains our first analysis of all Kepler data, as well as an automated assessment of these results," said SETI Institute scientist Jeffrey Coughlin. On Thursday, NASA released the latest catalog of exoplanet candidates, adding more than 500 new possible planets to the 4,175 already found by the space-based telescope. "Today, and thousands of discoveries later, astronomers are on the cusp of finding something people have dreamed about for thousands of years - another Earth," NASA said in a statement. The Kepler mission launched in 2009 to search for exoplanets, which are planets outside our solar system, particularly those about the size of Earth or smaller. "Kepler 452b could be experiencing now what the Earth will undergo more than a billion years from now, as the Sun ages and grows brighter." The water vapor would be lost from the planet forever," he added. "The increasing energy from its aging sun might be heating the surface and evaporating any oceans. "If Kepler 452b is indeed a rocky planet, its location vis-a-vis its star could mean that it is just entering a runaway greenhouse phase of its climate history," said Doug Caldwell, a Search for Extraterrestrial Intelligence (SETI) Institute scientist working on the Kepler mission. If the planet is rocky, and scientists believe that it has a better than even chance of being just that, then it could be in the midst of a fearful scenario, as the heat from its dying star evaporates Kepler 452b's lakes and oceans. ![]() Its star is four percent more massive than the Sun and 10 percent brighter. "Kepler 452b is orbiting a close cousin of our Sun, but one that is 1.5 billion years older," NASA said in a statement. Known as Kepler 452b, the planet was detected by the US space agency's Kepler Space Telescope, which has been hunting for other worlds like ours since 2009. That means the planet, which is 1,400 light-years away, could offer a glimpse into the Earth's apocalyptic future, scientists said. Not only is this planet squarely in the Goldilocks zone - where life could exist because it is neither too hot nor too cold to support liquid water - its star looks like an older cousin of our Sun, the US space agency said.
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