Discovery and validation of Kepler-452b: A 1.6 R{sub ⨁} super earth exoplanet in the habitable zone of a G2 star

Journal Article · Sat Aug 01 00:00:00 EDT 2015 · The Astronomical Journal (Online)

DOI:https://doi.org/10.1088/0004-6256/150/2/56· OSTI ID:22879439

Jenkins, Jon M.; Twicken, Joseph D.; Batalha, Natalie M.; Caldwell, Douglas A.; Seader, Shawn; Rowe, Jason F.; Bryson, Stephen T. ^[1]; Cochran, William D.; Endl, Michael; Ramirez, Ivan ^[2]; Latham, David W.; Esquerdo, Gilbert A.; Bieryla, Allyson; Torres, Guillermo; Buchhave, Lars ^[3]; Petigura, Erik; Marcy, Geoffrey W.; Isaacson, Howard ^[4]; Ciardi, David R. ^[5]; Huber, Daniel ^[6] ; others, and

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1. NASA Ames Research Center, Moffett Field, CA 94035 (United States)
2. McDonald Observatory and Department of Astronomy, University of Texas at Austin 2515 Speedway, Stop 1402, Austin, TX 78712 (United States)
3. Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States)
4. University of California, Berkeley, CA 94720 (United States)
5. NASA Exoplanet Science Institute/Caltech Pasadena, CA 91125 (United States)
6. SETI Institute, 189 Bernardo Avenue, Mountain View, CA 94043 (United States)

We report on the discovery and validation of Kepler-452b, a transiting planet identified by a search through the 4 years of data collected by NASA’s Kepler Mission. This possibly rocky 1.63{sub −0.20}{sup +0.23} R{sub ⊕} planet orbits its G2 host star every 384.843{sub −0.012}{sup +0.007} days, the longest orbital period for a small (R{sub P}<2 R{sub ⊕}) transiting exoplanet to date. The likelihood that this planet has a rocky composition lies between 49% and 62%. The star has an effective temperature of 5757 ± 85 K and a logg of 4.32 ± 0.09. At a mean orbital separation of 1.046{sub −0.015}{sup +0.019} AU, this small planet is well within the optimistic habitable zone of its star (recent Venus/early Mars), experiencing only 10% more flux than Earth receives from the Sun today, and slightly outside the conservative habitable zone (runaway greenhouse/maximum greenhouse). The star is slightly larger and older than the Sun, with a present radius of 1.11{sub −0.09}{sup +0.15} R{sub ⊙} and an estimated age of ∼6 Gyr. Thus, Kepler-452b has likely always been in the habitable zone and should remain there for another ∼3 Gyr.

• OSTI ID: 22879439
• Journal Information: The Astronomical Journal (Online), Vol. 150, Issue 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 1538-3881
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
DETECTION
EARTH PLANET
GREENHOUSES
MARS PLANET
NASA
ORBITS
SUN
VALIDATION
VENUS PLANET