NASA’s Kepler mission has confirmed the first near Earth-size planet in the “habitable zone” around a sun-like star.
Dubbed “Kepler-452b,” it is the smallest planet discovered to date orbiting in the habitable zone, the area around a star like Earth’s sun where liquid water could pool on its surface.
Kepler-452b is larger than Earth and orbits its sun in 385 days, an orbit that is only 5 percent longer than Earth’s. It is located 5 percent farther from its parent star than Earth is from the sun. Kepler-452 is 6 billion years old, 1.5 billion years older than our sun, has the same temperature, and is 20 percent brighter with a diameter 10 percent larger.
To confirm the finding and better determine the properties of the Kepler-452 system, a team of scientists performed ground-base observations from the University of Texas at Austin’s McDonald Observatory, the Fred Lawrence Whipple Observatory on Mt. Hopkins in Arizona and the W.M. Keck Observatory on top of Mauna Kea in Hawaii.
The Kepler-452 system is located 1,400 light-years away in the constellation Cygnus.
In addition, the Kepler team has increased the number of new exoplanet candidates by 521 from their analysis of observations conducted from May 2009 to May 2013. The number of planet candidates detected by the Kepler mission is now 4,696. These candidates require follow-up observations and analysis to verify they are actual planets.
Twelve of the new planet candidates have diameters between one to two times that of Earth, and orbit in their star’s habitable zone. Of these, nine orbit stars that are similar to our sun in size and temperature.
These findings are presented in the seventh Kepler Candidate Catalog and will be submitted for publication in the Astrophysical Journal. Data publicly available on the NASA Exoplanet Archive was used to make the discovery.
Scientists are now producing the last catalog based on the original Kepler mission’s four-year data collection. The final analysis will be conducted using sophisticated software that is increasingly sensitive to the tiny telltale signatures of Earth-size planets.