Scientists from NASA have reported that the Kepler Space Telescope has found what appears to be the most Earth-like exoplanet that astronomers have seen so far. The newly discovered planet lies within its star system's own "Goldilocks Zone" sparking hopes of discovering extraterrestrial life.
The Goldilocks Zone, also known as the "habitable zone" is an area where the distance between the planet and its own sun is "just right." Temperatures in the habitable zone are neither too hot nor too cold and water is known to exist in its liquid form.
"The discovery of Kepler-186f is a significant step toward finding worlds like our planet Earth," said NASA Astrophysics Division director Paul Hertz. "Future NASA missions, like the Transiting Exoplanet Survey Satellite and the James Webb Space Telescope, will discover the nearest rocky exoplanets and determine their composition and atmospheric conditions, continuing humankind's quest to find truly Earth-like worlds."
In the past, astronomers have already found a number of planets located within their systems' respective habitable zones. However, these planets were often too big being 40 percent larger than Earth at the minimum. Due to the differences in size, scientists have been at a loss regarding the makeup of these planets. Because Kepler-186f is relatively similar to the Earth in terms of size, scientists can make more probable speculations and predictions about its makeup.
"We know of just one planet where life exists -- Earth. When we search for life outside our solar system we focus on finding planets with characteristics that mimic that of Earth," said Search for Extraterrestrial Intelligence (SETI) Institute researcher Elisa Quintana. "Finding a habitable zone planet comparable to Earth in size is a major step forward." Quintana is the lead author of a paper on Kepler-186, which was published in the online journal Science.
While NASA astronomers have confirmed the size of the newfound exoplanet, little is currently known about its composition and its mass. Due to the size of the planet however, scientists say that the odds of good that the planet is rocky.
The new planet was found in the Kepler-186 system approximately 500 light years away from Earth. The system is located in the constellation Cygnus. Due to the fact that this is the most Earth-like exoplanet Kepler has ever found, scientists from the SETI Institute are keen on learning more about the planet.
"Being in the habitable zone does not mean we know this planet is habitable. The temperature on the planet is strongly dependent on what kind of atmosphere the planet has," said Bay Area Environmental Research Institute researcher and paper co-author Thomas Barclay. "Kepler-186f can be thought of as an Earth-cousin rather than an Earth-twin. It has many properties that resemble Earth."