January 10

There could be a lot of Earth-like planets out there, new analysis of data from NASA’s Kepler telescope suggests. Our Milky Way is home to at least 17 billion planets that are similar in size to Earth, a new estimate suggests. Astronomers say that one in six stars hosts an Earth-sized planet in a close orbit – suggesting a total of 17 billion such planets in our galaxy. In 1750, British astronomer Thomas Wright published a book An Original Theory or New Hypothesis of the Universe with a diagram showing the stars of our Milky Way, each surrounded by orbiting planets. Planets just like home — roughly the size of Earth and residing at a distance from a star where water would be liquid — are likely to orbit some of the stars nearest to the Solar System, according to a new statistical study using data from NASA’s Kepler telescope. It was a major feat last year when a team of astronomers announced it had detected two Earth-sized planets, circling very close to a star called Kepler-20, which is 950 light-years away. New estimates suggest that roughly 50 percent of sun-like stars could have planets the size of Earth orbiting in a place where liquid water might exist on their surface. This week the American Astronomical Society (AAS) is meeting in Long Beach. We still don’t know if Earth, as a planet that currently harbors life, is alone in the universe. Enough planets exist in the Milky Way to ensure that there is at least one for each of the hundred million stars in the galaxy, NASA has revealed. Two years ago, mission scientists for NASA’s Kepler space observatory announced the discovery of a mind-boggling 1,235 new planet candidates, each revealed by the tiny dip in brightness created as it passed in front of its host star. Classed as a “super-Earth,” candidate planet KOI (Kepler Object of Interest) 172.02 orbits within the habitable zone of a sun-like star. A new study has shown that the number of exoplanets – planets outside of our solar system – discovered by NASA’s Kepler may be inflated by over a third. The Milky Way is awash in planets by the billions, and astronomers are finding more every day.