Theoretical human friendly world with two moons revolving about a red small celebrity. Astronomers have found that 6 percent of all red small celebrities have an Earth-sized world in the human friendly area, which is heated enough for fluid water on the earth's surface. Since red small celebrities are so common, then in past statistics the nearest Earth-like world should be only 13 light-years away.
Using openly available information from NASA's Kepler area telescope, astronomers at the Harvard-Smithsonian Middle for Astrophysics (CfA) have discovered that six % of red small celebrities have human friendly, Earth-sized planet's. Since red dwarves are the most typical celebrities in our universe, the nearest Earth-like world could be just 13 light-years away.
"We believed we would have to search wide ranges to find an Earth-like world. Now we recognize another World is probably in our own lawn, patiently waiting to be identified," said Stanford uranologist and cause writer Courtney Putting on a costume (CfA).
Dressing provided her results these days in a media meeting at the Harvard-Smithsonian Middle for Astrophysics in Arlington, Bulk.
Red small celebrities are smaller sized, chilly, and fainter than our Sun. A typical red small is only one-third as huge and one-thousandth as shiny as the Sun. From World, no red small is noticeable to the undressed eye.
Despite their dimness, these stars are good places to look for Earth-like planets. Red dwarfs make up three out of every four stars in our galaxy for a total of at least 75 billion. The signal of a transiting planet is larger since the star itself is smaller, so an Earth-sized world blocks more of the star's disk. And since a planet has to orbit a cool star closer in order to be in the habitable zone, it's more likely to transit from our point of view.
Dressing culled the Kepler catalog of 158,000 target stars to identify all the red dwarfs. She then reanalyzed those stars to calculate more accurate sizes and temperatures. She found that almost all of those stars were smaller and cooler than previously thought.
Since the size of a transiting planet is determined relative to the star size, based on how much of the star's disk the planet covers, shrinking the star shrinks the planet. And a cooler star will have a tighter habitable zone.
Dressing identified 95 planetary candidates orbiting red dwarf stars. This implied that at least 60 percent of such stars have planets smaller than Neptune. However, most weren't quite the right size or temperature to be considered truly Earth-like. Three planetary candidates were both warm and approximately Earth-sized. Statistically, this means that six percent of all red dwarf stars should have an Earth-like planet.
"We now know the rate of occurrence of habitable planets around the most common stars in our galaxy," said co-author David Charbonneau (CfA). "That rate implies that it will be significantly easier to search for life beyond the solar system than we previously thought."
Our Sun is surrounded by a swarm of red dwarf stars. About 75 percent of the closest stars are red dwarfs. Since 6 percent of those should host habitable planets, the closest Earth-like world is likely to be just 13 light-years away.
Locating nearby, Earth-like worlds may require a dedicated small space telescope, or a large network of ground-based telescopes. Follow-up studies with instruments like the Giant Magellan Telescope and James Webb Space Telescope could tell us whether any warm, transiting planets have an atmosphere and further probe its chemistry.
