Kepler-28b

Last updated
Kepler-28b
Discovery [1]
Discovered by Jason Steffen et al.
Discovery site Kepler Space Observatory
Discovery date25 January 2012
Transit
Orbital characteristics
0.05375 AU (8,041,000 km) [2]
5.91227 [2] d
Star Kepler-28
Physical characteristics
Mean radius
2.41+0.04
−0.17
[2] R🜨
Mass 8.8+3.8
3.1
ME [3]
Temperature 743 K [3]

    Kepler-28b is an extrasolar planet orbiting the star Kepler-28. It is a transiting planet that is smaller than Jupiter that orbits very closely to Kepler-28.

    Contents

    Host star

    Kepler-28 is the host star of Kepler-28b, and is alternatively known as KOI-870 and KIC 6949607. The star is smaller, less massive, and cooler than the Sun, with (respectively) a radius 0.7 times of the Sun; a mass 0.75 times of the Sun; and an effective temperature of 4590 K. [4] The star has a high metallicity with relation to the Sun, equal to [M/H] = 0.34. With an apparent magnitude of 15.05, Kepler-28 is invisible to the naked eye from Earth, requiring a medium-size telescope to see it. [5]

    Characteristics

    Kepler-28b is a gas giant. Upon discovery, it was poorly characterized, with only an upper mass limit of 1.51  times the mass of Jupiter (which, given its radius, would imply an impossibly low density) ascertained from dynamical simulations. The planet transits its host star over 2.77 hours of each orbit, making a shadow we can detect from earth. [5] In 2016 improved radial velocity data made it possible to classify Kepler-28b as a small (sub-Neptune) gas giant. [3]

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    <span class="mw-page-title-main">Kepler-1647b</span> Circumbinary gas giant orbiting the Kepler-1647 star system

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    References

    1. Steffen, J.; Fabrycky, D. (2012). "Transit Timing Observations from Kepler: III. Confirmation of 4 Multiple Planet Systems by a Fourier-Domain Study of Anti-correlated Transit Timing Variations" (PDF). Monthly Notices of the Royal Astronomical Society. 421 (3): 2342. arXiv: 1201.5412v1 . Bibcode:2012MNRAS.421.2342S. doi:10.1111/j.1365-2966.2012.20467.x. S2CID   11898578. Archived (PDF) from the original on 2018-11-04. Retrieved 2018-11-04.
    2. 1 2 3 "Kepler-28 b". NASA Exoplanet Archive. Archived from the original on 21 October 2021. Retrieved 23 January 2017.
    3. 1 2 3 Cubillos, Patricio; Erkaev, Nikolai V.; Juvan, Ines; Fossati, Luca; Johnstone, Colin P.; Lammer, Helmut; Lendl, Monika; Odert, Petra; Kislyakova, Kristina G. (2016), "An overabundance of low-density Neptune-like planets", Monthly Notices of the Royal Astronomical Society, 466 (2): 1868–1879, arXiv: 1611.09236 , doi:10.1093/mnras/stw3103
    4. "Star: Kepler-28". Extrasolar Planets Encyclopaedia . 2012. Archived from the original on 26 April 2012. Retrieved 22 June 2012.
    5. 1 2 "Kepler Table of Discoveries". Kepler Mission . Ames Research Center, NASA. 2012. Archived from the original on 2010-05-27. Retrieved 22 June 2012.