Kepler-62b

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Kepler-62b
Exoplanet List of exoplanets
Parent star
Star Kepler-62 (KOI-701)
Constellation Lyra
Right ascension (α) 18h 52m 51.06019s
Declination (δ) +45° 20′ 59.507″
Apparent magnitude (mV) 13.654[1]
Mass (m) 0.69 (± 0.02)[2] M
Radius (r) 0.64 (± 0.02)[2] R
Temperature (T) 4925 (± 70)[2] K
Metallicity [Fe/H] −0.37 (± 0.04)[2]
Age 7 (± 4)[2] Gyr
Physical characteristics
Mass (m) ≤9 M
Radius (r) 1.31 (± 0.04)[2] R
Stellar flux (F) 70 ± 9
Temperature (T) 750 K (477 °C; 890 °F)
Orbital elements
Semi-major axis (a) 0.0553[2] AU
Eccentricity (e) ~0[2]
Orbital period (P) 5.714932[2] d
Inclination (i) 89.2 (±0.4)[2]°
Discovery information
Discovery date 18 April 2013[2]
Discoverer(s) Borucki et al.
Discovery method Transit (Kepler Mission)[2]
Other detection methods Transit timing variations
Discovery site Kepler Space Observatory
Discovery status Published refereed article
Other designations
KOI-701.02, K00701.02; KOI-701 b; 2MASS J18525105+4520595 b; KIC 9002278 b; WISE J185251.03+452059.0 b
Database references
Extrasolar Planets
Encyclopaedia
data
SIMBAD data
Exoplanet Archive data
Open Exoplanet Catalogue data

Kepler-62b is the innermost and the second smallest discovered exoplanet orbiting the star Kepler-62, with a diameter roughly 30% larger than Earth. It was found using the transit method, in which the dimming effect that a planet causes as it crosses in front of its star is measured. It is likely to have an equilibrium temperature slighly higher than the surface temperature of Venus (around 750 K (477 °C; 890 °F)), high enough to melt some types of metal.[2] Its stellar flux is 70 ± 9 times Earth's.[2]

Characteristics[edit]

The Kepler Space Telescope search volume, in the context of the Milky Way Galaxy.

Mass, radius and temperature[edit]

Kepler-62b is a super-Earth, an exoplanet with a radius and mass bigger than Earth, but smaller than that of the ice giants Neptune and Uranus. It has an equilibrium temperature of 750 K (477 °C; 890 °F). This is hot enough to melt some types of metal. It has a radius of 1.3 R,[2] placing it below the estimated radius of ≤1.6 R where it would otherwise be a mini-Neptune with a volatile composition, with no solid surface.[3] However, the mass is currently not known, estimates place an upper limit of <9 M, the real mass is expected to be significantly lower than this.[2]

Host star[edit]

The planet orbits a (K-type) star named Kepler-62, orbited by a total of five planets, of which Kepler-62f has the longest orbital period.[2] The star has a mass of 0.69 M and a radius of 0.64 R. It has a temperature of 4925 K and is 7 billion years old.[2] In comparison, the Sun is 4.6 billion years old[4] and has a surface temperature of 5778 K.[5]

The star's apparent magnitude, or how bright it appears from Earth's perspective, is 13.65. Therefore, it is too dim to be seen with the naked eye.

Orbit[edit]

Kepler-62b orbits its host star with about 21% of the Sun's luminosity with an orbital period of 5 days and an orbital radius of about 0.05times that of Earth's (compared to same distance as Mercury from the Sun, which is about 0.38 AU).

Discovery[edit]

In 2009, NASA's Kepler spacecraft was completing observing stars on its photometer, the instrument it uses to detect transit events, in which a planet crosses in front of and dims its host star for a brief and roughly regular period of time. In this last test, Kepler observed 50000 stars in the Kepler Input Catalog, including Kepler-62; the preliminary light curves were sent to the Kepler science team for analysis, who chose obvious planetary companions from the bunch for follow-up at observatories. Observations for the potential exoplanet candidates took place between 13 May 2009 and 17 March 2012. After observing the respective transits, which for Kepler-62b occurred roughly every 5 days (its orbital period), it was eventually concluded that a planetary body was responsible for the periodic 5-day transits. The discovery, along with the planetary system of the star Kepler-69 were announced on April 18, 2013.[2]

References[edit]

  1. ^ "Kepler Input Catalog search result". Space Telescope Science Institute. Retrieved 2013-04-18. 
  2. ^ a b c d e f g h i j k l m n o p q r s Borucki, William J.; et al. (18 April 2013). "Kepler-62: A Five-Planet System with Planets of 1.4 and 1.6 Earth Radii in the Habitable Zone". Science Express 340: 587–90. arXiv:1304.7387. Bibcode:2013Sci...340..587B. doi:10.1126/science.1234702. PMID 23599262. Retrieved 18 April 2013. 
  3. ^ https://astrobites.org/2014/07/31/most-1-6-earth-radius-planets-are-not-rocky/
  4. ^ Fraser Cain (16 September 2008). "How Old is the Sun?". Universe Today. Retrieved 19 February 2011. 
  5. ^ Fraser Cain (15 September 2008). "Temperature of the Sun". Universe Today. Retrieved 19 February 2011. 

Coordinates: Sky map 18h 52m 51.06019s, +45° 20′ 59.507″