Kepler-28

Last updated
Kepler-28
Kepler-28.jpg
Kepler-28 compared to the Sun
Observation data
Epoch J2000       Equinox J2000
Constellation Cygnus [1]
Right ascension 19h 28m 32.8905s [2]
Declination +42° 25 45.959 [2]
Apparent magnitude  (V)15.306 [3]
Characteristics
Spectral type M0V [4]
Astrometry
Radial velocity (Rv)−26.99±6.00 [2]  km/s
Proper motion (μ)RA: −0.463(21)  mas/yr [2]
Dec.: 11.691(21)  mas/yr [2]
Parallax (π)2.2537 ± 0.0185  mas [2]
Distance 1,450 ± 10  ly
(444 ± 4  pc)
Details
Mass 0.684±0.026 [5]   M
Radius 0.664±0.013 [5]   R
Temperature 4499±75 [5]   K
Metallicity [Fe/H]−0.17±0.11 [4]   dex
Rotation 17.951±0.016 days [6]
Rotational velocity (v sin i)0.6 [3]  km/s
Age 2.2 [7]   Gyr
Other designations
KOI-870, KIC  6949607, 2MASS J19283288+4225459 [8]
Database references
SIMBAD data
KIC data

Kepler-28 is an M-type main-sequence star about 1,450 light-years (440 parsecs ) away in the northern constellation of Cygnus. [2] With an apparent visual magnitude of 15.036, [3] this star is too faint to be seen with the naked eye. It is orbited by two exoplanets.

Planetary system

The two transiting planets of Kepler-28 were discovered in 2011 using the Kepler space telescope, and were confirmed in early 2012. [9] They are both warm sub-Neptune gas planets. [7] The planetary parameters were updated in 2023, with lower values for all of mass, radius, and density compared to previous estimates. [5]

The Kepler-28 planetary system [4] [5]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b 1.63+0.51
−0.40
  M🜨
0.0625.91213(17)<0.081.959+0.043
−0.042
  R🜨
c2.06+0.70
−0.52
  M🜨
0.0818.98597(27)0.017+0.023
−0.014
1.857±0.042  R🜨

Related Research Articles

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Kepler-39 is an F-type main sequence star located in the constellation Cygnus. It is located about 3,500 light-years away. One known substellar companion orbits it, Kepler-39b.

<span class="mw-page-title-main">Kepler-46</span> Old star with a planetary system

Kepler-46, previously designated KOI-872, is a star located in the constellation Lyra. Observed since 2009 by the Kepler space observatory, it has since been found to possess a planetary system consisting of at least three planets and while it has a similar mass to the Sun (90%) it is significantly older at ten billion years.

Kepler-32 is an M-type main sequence star located about 1053 light years from Earth, in the constellation of Cygnus. Discovered in January 2012 by the Kepler spacecraft, it shows a 0.58 ± 0.05 solar mass (M), a 0.53 ± 0.04 solar radius (R), and temperature of 3900.0 K, making it half the mass and radius of the Sun, two-thirds its temperature and 5% its luminosity.

Kepler-65 is a subgiant star slightly more massive than the Sun and has at least four planets.

Kepler-66 is a star with slightly more mass than the Sun in the NGC 6811 open cluster in the Cygnus constellation. It has one confirmed planet, slightly smaller than Neptune, announced in 2013.

Kepler-67 is a star in the open cluster NGC 6811 in the constellation Cygnus. It has slightly less mass than the Sun and has one confirmed planet, slightly smaller than Neptune, announced in 2013.

Kepler-88 is a G-type star 1,230 light-years away in the constellation of Lyra, with three confirmed exoplanets. SIMBAD lists a subgiant spectral type of G8IV, while other sources give it a main sequence spectral type of G6V. The latter is more consistent with its properties.

<span class="mw-page-title-main">Kepler-23</span> Star in the constellation Cygnus

Kepler-23 is a G-type main-sequence star about 2,860 light-years away in the northern constellation of Cygnus, the swan. With an apparent visual magnitude of 13.5, it is too faint to be seen with the naked eye. This star is similar in mass and temperature to the Sun, but is larger and more luminous. Kepler-23 is orbited by three known exoplanets.

Kepler-24 is a star in the northern constellation of Lyra. It is located at the celestial coordinates: Right Ascension 19h 21m 39.1857s, Declination +38° 20′ 37.450″. With an apparent visual magnitude of 15.5, this star is too faint to be seen with the naked eye.

<span class="mw-page-title-main">Kepler-25</span> Yellow-white hued star in the constellation Lyra

Kepler-25 is a star in the northern constellation of Lyra. It is slightly larger and more massive than the Sun, with a luminosity 212 times that of the Sun. With an apparent visual magnitude of 10.6, this star is too faint to be seen with the naked eye.

<span class="mw-page-title-main">Kepler-26</span> Star in the constellation Lyra

Kepler-26 is a star in the northern constellation of Lyra. It is located at the celestial coordinates: Right Ascension 18h 59m 45.8408s Declination +46° 33′ 59.438″. With an apparent visual magnitude of 15.5, this star is too faint to be seen with the naked eye.

Kepler-102 is a star 353 light-years away in the constellation of Lyra. Kepler-102 is less luminous than the Sun. The star system does not contain any observable amount of dust. Kepler-102 is suspected to be orbited by a binary consisting of two red dwarf stars, at projected separations of 591 and 627 AU.

Kepler-61 is a K-type main-sequence star approximately 1,100 light years from Earth in the constellation Cygnus. It is located within the field of vision of the Kepler spacecraft, the satellite that NASA's Kepler Mission used to detect planets that may be transiting their stars. On April 24, 2013 it was announced that the star has an extrasolar planet orbiting in the inner edge of the habitable zone, named Kepler-61b.

Kepler-30 is a star in the northern constellation of Lyra. It is located at the celestial coordinates: Right Ascension 19h 01m 08.0746s Declination +38° 56′ 50.218″. With an apparent visual magnitude of 15.5, this star is too faint to be seen with the naked eye. Kepler-30 is exhibiting a strong starspot activity.

Kepler-43, formerly known as KOI-135, is a star in the northern constellation of Cygnus. It is located at the celestial coordinates: Right Ascension 19h 00m 57.8034s, Declination +46° 40′ 05.665″. With an apparent visual magnitude of 13.996, this star is too faint to be seen with the naked eye. The Kepler-43 has a very strong starspot activity.

Kepler-45, formerly known as KOI-254, is a star in the northern constellation of Cygnus. It is located at the celestial coordinates: right ascension 19h 31m 29.495s, declination +41° 03′ 51.37″. With an apparent visual magnitude of 16.88, this star is too faint to be seen with the naked eye.

<span class="mw-page-title-main">KOI-256</span> Double star in the constellation Cygnus

KOI-256 is a double star located in the constellation Cygnus approximately 575 light-years (176 pc) from Earth. While observations by the Kepler spacecraft suggested the system contained a gas giant exoplanet orbiting a red dwarf, later studies determined that KOI-256 was a binary system composed of the red dwarf orbiting a white dwarf.

Kepler-419 is an F-type main-sequence star located about 3,280 light years from Earth in the constellation Cygnus. It is located within the field of vision of the Kepler spacecraft, the satellite that NASA's Kepler Mission used to detect planets that may be transiting their stars. In 2012, a potential planetary companion in a very eccentric orbit was detected around this star, but its planetary nature was not confirmed until 12 June 2014, when it was named Kepler-419b. A second planet was announced orbiting further out from the star in the same paper, named Kepler-419c.

References

  1. "Cygnus – constellation boundary", The Constellations, International Astronomical Union , retrieved 2011-12-15
  2. 1 2 3 4 5 6 7 Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv: 2208.00211 . Bibcode:2023A&A...674A...1G. doi: 10.1051/0004-6361/202243940 . S2CID   244398875. Gaia DR3 record for this source at VizieR.
  3. 1 2 3 Kepler-28b, NASA Ames Research Center, archived from the original on 2012-05-03, retrieved 2011-12-06
  4. 1 2 3 Muirhead, Philip S.; Hamren, Katherine; et al. (May 2012). "Characterizing the Cool Kepler Objects of Interests. New Effective Temperatures, Metallicities, Masses, and Radii of Low-mass Kepler Planet-candidate Host Stars". The Astrophysical Journal Letters . 750 (2): L37. arXiv: 1109.1819 . Bibcode:2012ApJ...750L..37M. doi:10.1088/2041-8205/750/2/L37.
  5. 1 2 3 4 5 Leleu, A.; Delisle, J.-B.; et al. (January 2023). "Removing biases on the density of sub-Neptunes characterised via transit timing variations. Update on the mass-radius relationship of 34 Kepler planets". Astronomy & Astrophysics . 669: A117. arXiv: 2207.07456 . Bibcode:2023A&A...669A.117L. doi:10.1051/0004-6361/202244132.
  6. McQuillan, A.; Mazeh, T.; Aigrain, S. (2013). "Stellar Rotation Periods of The Kepler objects of Interest: A Dearth of Close-In Planets Around Fast Rotators". The Astrophysical Journal Letters. 775 (1). L11. arXiv: 1308.1845 . Bibcode: 2013ApJ...775L..11M . doi: 10.1088/2041-8205/775/1/L11 .
  7. 1 2 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 , Bibcode:2017MNRAS.466.1868C, doi:10.1093/mnras/stw3103, S2CID   119408956
  8. "Kepler-28". SIMBAD . Centre de données astronomiques de Strasbourg . Retrieved 10 January 2017.
  9. Steffen, Jason H.; Fabrycky, Daniel C.; Ford, Eric B.; Carter, Joshua A.; Desert, Jean-Michel; Fressin, Francois; Holman, Matthew J.; Lissauer, Jack J.; Moorhead, Althea V.; Rowe, Jason F.; Ragozzine, Darin; Welsh, William F.; Batalha, Natalie M.; Borucki, William J.; Buchhave, Lars A.; Bryson, Steve; Caldwell, Douglas A.; Charbonneau, David; Ciardi, David R.; Cochran, William D.; Endl, Michael; Everett, Mark E.; Gautier III, Thomas N.; Gilliland, Ron L.; Girouard, Forrest R.; Jenkins, Jon M.; Horch, Elliott; Howell, Steve B.; Isaacson, Howard; et al. (2012), Transit Timing Observations from Kepler: III. Confirmation of 4 Multiple Planet Systems by a Fourier-Domain Study of Anti-correlated Transit Timing Variations, arXiv: 1201.5412 , Bibcode:2012MNRAS.421.2342S, doi:10.1111/j.1365-2966.2012.20467.x, S2CID   11898578