HD 102956 b

Last updated
HD 102956 b / Isagel
Artistic impression of HD102956.png
Artist's impression HD 102956 b
Discovery [1]
Discovered by Johnson et al.
Discovery site Keck Observatory
Discovery date2010
Doppler spectroscopy
Orbital characteristics [2]
0.0807±0.0073  AU
Eccentricity 0.037±0.019
6.49470±0.00019 d
2455351.45±0.64  JD
301±33 º
Semi-amplitude 74.6±1.8  m/s
Star HD 102956
Physical characteristics [2]
Mass ≥0.960±0.023  MJ
    HD 102956
    Observation data
    Epoch J2000       Equinox J2000
    Constellation Ursa Major
    Right ascension 11h 51m 22.5111s [3]
    Declination +57° 38′ 26.6427″ [3]
    Characteristics
    Evolutionary stage Main sequence
    Spectral type A
    Astrometry
    Radial velocity (Rv)−25±83 km/s
    Proper motion (μ)RA: −11.24±0.049 [3]   mas/yr
    Dec.: −17.578±0.049 [3]   mas/yr
    Parallax (π)8.1753 ± 0.0290  mas [3]
    Distance 399 ± 1  ly
    (122.3 ± 0.4  pc)
    Absolute magnitude  (MV)2.5
    Details
    Mass 1.68±0.11  M☉
    Radius 4.4±0.1  R☉
    Luminosity (visual, LV)11.6±0.5  L☉
    Temperature 5054±44  K
    Metallicity [Fe/H]+0.19±0.04  dex
    Rotational velocity (v sin i)0.30 km/s
    Other designations
    BD+58 1340, HIP  57820, SAO  28161, TYC  3839-00846-1, 2MASS J11512253+5738267 [4]
    Database references
    SIMBAD data
    Exoplanet Archive data

    HD 102956 b or Isagel is an extrasolar planet discovered in 2010 by a team of American astronomers led by John Johnson using Doppler spectroscopy and the Keck Observatory in Hawaii. HD 102956 b is in the orbit of host star HD 102956. The planet is at most the mass of Jupiter, orbiting every 6.5 days at a distance of 12 million km. HD 202956 b has a very circular orbit. [1] The system is roughly 399 light years from us.

    Contents

    Discovery and nomenclature

    HD 102956 is located inside the Big Dipper. HD102956b location.png
    HD 102956 is located inside the Big Dipper.

    The name HD 102956 derives directly from the fact that the star is the 102,956th star catalogued in the Henry Draper catalog. The designation of b is given to the first planet orbiting a given star.

    The star is one of the 2.5 million brightest stars in the sky and is part of the Tycho-2 Catalogue. It is not visible to the naked eye with an apparent magnitude of 8.

    NameExoWorlds

    In 2019 this planet was announced as part of the IAU NameExoWorlds project [5] where it was designated as the planet that will be named by Sweden. The winning proposal was Isagel, from Nobel laureate Harry Martinson's space poem Aniara . [6]

    Host star

    HD 102956 (Aniara) is an orange subgiant with a mass and radius of 1.68 M☉ and 4.4 R☉, respectively. The surface temperature is about 5,054 K (4,781 °C). The star is 11.6 times brighter than the Sun. The star's age is estimated at 2.3 billion years.

    Related Research Articles

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    HD 221420 is a likely binary star system in the southern circumpolar constellation Octans. It has an apparent magnitude of 5.81, allowing it to be faintly seen with the naked eye. The object is relatively close at a distance of 102 light years but is receding with a heliocentric radial velocity of 26.5 km/s.

    References

    1. 1 2 Johnson, John Asher; et al. (2010). "A Hot Jupiter Orbiting the 1.7 M☉ Subgiant HD 102956". The Astrophysical Journal Letters. 721 (2): L153–L157. arXiv: 1007.4555 . Bibcode: 2010ApJ...721L.153J . doi: 10.1088/2041-8205/721/2/L153 .
    2. 1 2 Luhn, Jacob K.; et al. (2019). "Retired A Stars and Their Companions. VIII. 15 New Planetary Signals around Subgiants and Transit Parameters for California Planet Search Planets with Subgiant Hosts". The Astronomical Journal. 157 (4). 149. arXiv: 1811.03043 . Bibcode:2019AJ....157..149L. doi: 10.3847/1538-3881/aaf5d0 . S2CID   102486961.
    3. 1 2 3 4 5 Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics . 616. A1. arXiv: 1804.09365 . Bibcode: 2018A&A...616A...1G . doi: 10.1051/0004-6361/201833051 . Gaia DR2 record for this source at VizieR.
    4. ↑ "HD 102956". SIMBAD . Centre de données astronomiques de Strasbourg . Retrieved 2019-09-21.
    5. ↑ "Name an exoplanet (press release)". 2019-06-06. Archived from the original on 2019-06-08. Retrieved 2019-06-13.
    6. ↑ "Rymddikt gav namn åt Sveriges exoplanet" (in Swedish). 2019-12-17. Archived from the original on 2020-01-12. Retrieved 2021-08-10.
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