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an open source database of all discovered extrasolar planets

Kepler-21

The planetary system Kepler-21 hosts at least one planet. Note that the system is a multiple star system. It hosts at least 2 stellar components.

  System parameters
Primary system name Kepler-21
Alternative system names KOI-975, KIC 3632418
Right ascension 19 09 26.83535
Declination +38 42 50.4593
Distance [parsec] 113±7
Distance [lightyears] 368±24
Number of stars in system 2
Number of planets in system 1

ArchitectureArchitecture of the system

This list shows all planetary and stellar components in the system. It gives a quick overview of the hierarchical architecture.

  •  Stellar binary
    •  Kepler-21 A, stellar object
      •  Kepler-21 b, planet, semi-major axis: 0.0425±0.0001 AU
      •  Kepler-21 B, stellar object

      PlanetsPlanets in the system

      This table lists all planets in the system Kepler-21.

        Kepler-21 b
      Alternative planet names Kepler-21 A b, HIP 94112 b, TYC 3120-00963-1 b, HD 179070 b, HD 179070 A b, BD+38 3455 A b, SAO 67891 b, 2MASS J19092683+3842505 b, KIC 3632418 b, KOI-975.01, KOI-975 b, KOI-975 A b
      Description This planet has been discovered with the Kepler spacecraft. It is orbiting Kepler's brightest host star and is only 1.6 times larger than the Earth.
      Lists Confirmed planets; Planets in binary systems, S-type
      Mass [Mjup] < 0.0327
      Mass [Mearth] < 10.3930
      Radius [Rjup] 0.146+0.003−0.004
      Radius [Rearth] 1.63±0.04
      Orbital period [days] 2.7858±0.0000
      Semi-major axis [AU] 0.0425±0.0001
      Eccentricity N/A
      Equilibrium temperature [K] N/A
      Discovery method transit
      Discovery year 2011
      Last updated [yy/mm/dd] 16/01/22

      starStars in the system

      This table lists all stars in the system Kepler-21.

        Kepler-21 A Kepler-21 B
      Alternative star names KOI-975 A, KIC 3632418 A, HIP 94112, TYC 3120-963-1, SAO 67891, BD+38 3455 A, 2MASS J19092683+3842505 KOI-975 B, KIC 3632418 B, HD 179070 B, BD+38 3455 B
      Mass [MSun] 1.340±0.010 0.42+0.14−0.32
      Radius [RSun] 1.86±0.02 N/A
      Age [Gyr] N/A N/A
      Metallicity [Fe/H] -0.15±0.06 N/A
      Temperature [K] 6131±44 N/A
      Spectral type F6IV N/A
      Visual magnitude 8.250±0.010 N/A

      Planet sizes

      The following plot shows the approximate sizes of the planets in this system The Solar System planets are shown as a comparison. Note that unless the radius has been determined through a transit observation, this is only an approximation (see Lissauer et al. 2011b).

      PlutoMercuryMarsVenusEarthNeptuneUranusSaturnJupiterKepler-21 b

      Habitable zone

      The following plot shows the approximate location of the planets in this system with respect to the habitable zone (green) and the size of the star (red). This is only an estimate, using the star's spectral type and mass. Note that if no green band is shown in the plot, then the planet's orbit is far outside the habitable zone. The equations of Selsis, Kasting et al are used to draw the inner and outer boundaries.

      Kepler-21 b

      referencesScientific references and contributors

      Links to scientific papers and other data sources

      history http://arxiv.org/abs/1601.01524
      history http://phl.upr.edu/projects/habitable-exoplanets-catalog/data/database
      history http://adsabs.harvard.edu/abs/2012ApJ...746..123H
      history http://cdsbib.u-strasbg.fr/cgi-bin/cdsbib?2003yCat.2246....0C

      This table lists all links which are relevant to this particular system. Note that this is just a summary. More references to the scientific publications and comments can be found in the commit messages. To see these, head over the github or click here to directly go to the git blame output of this system. In the left column of the output you can see the commit message corresponding to each parameter. It also lists the date of the last commit and the person making the changes. Within the commit message, you will find a link to the scientific publication where the data is taken from. Note that this is a new feature and not all system parameters might have a reference associated with it yet. Please help making this catalogue better and contribute data or references!

      Open Exoplanet Catalogue contributors

      Contributor E-mail Number of commits
      Andrew Tribick ajtribick(at)googlemail.com 4
      Hanno Rein hanno(at)hanno-rein.de 5
      Marc-Antoine Martinod marc-antoine.martinod(at)ens-cachan.fr 2
      Ryan Varley ryanjvarley(at)gmail.com 4

      This table lists all people who have contributed to the Open Exoplanet Catalogue. Please consider contributing! Click here to find out how. You can also view all commits contributing to this file on github.

      xmlData download

      You can download the xml file corresponding to this planetary system, which is part of the Open Exoplanet Catalogue. All information on this page has been directly generated from this XML file. You can also download the entire catalogue over at github. If you prefer to download the dataset as an ASCII tables, you might find the oec_tables repository useful.

      correctionsCorrections

      If you spot an error or if you can contribute additional data to this entry, please send an e-mail to exoplanet@hanno-rein.de. Please include the corrected xml file and a reference to where the new data is coming from, ideally a scientific paper. If you are fluent with git and github, you can also create a pull request or open an issue on the Open Exoplanet Catalogue repository. Please include the reference to the relevant scientific paper in your commit message.