HD 180902 b

Last updated
HD 180902 b
Discovery [1]
Discovered by Johnson et al.
Discovery site Keck Observatory
Discovery date2010
Doppler spectroscopy
Orbital characteristics [2]
1.40±0.11  AU
Eccentricity 0.107±0.022
510.9±1.5 d
2455055±17  JD
181±12 º
Semi-amplitude 34.25±0.84  m/s
Star HD 180902
Physical characteristics [2]
Mean radius
1.221  RJ
Mass ≥1.685±0.041  MJ

    HD 180902 b is an extrasolar planet orbiting the K-type star HD 180902 approximately 342 light years away [3] in the constellation Sagittarius. [1]

    Contents

    Discovery

    HD 180902 b, along with other planets, was discovered in 2010 by scientists at the Keck Observatory. These planets were discovered via doppler spectroscopy, which is detecting exoplanets using the star's wobble.

    Properties

    Orbit

    HD 180902 b takes 510 days to orbit its parent star, which is longer than Earth's orbital period, which is 365 days. It orbits at a distance similar to Earth from the sun. HD 180902 orbits with mild eccentricity.

    Characteristics

    HD 180902 b has a minimum mass of 1.685 times the mass of Jupiter, but since its inclination is not known, the true mass of the planet cannot be detected. According to a theoretical search by the observatory, it may have a radius that is 22.1% larger than Jupiter.

    Size comparison
    JupiterHD 180902 b
    Small Jupiter.jpg Exoplanet sphere.jpg

    See also

    Related Research Articles

    <span class="mw-page-title-main">HD 80606 and HD 80607</span> Binary star system in the constellation Ursa Major

    HD 80606 and HD 80607 are two stars comprising a binary star system. They are approximately 217 light-years away in the constellation of Ursa Major. Both stars orbit each other at an average distance of 1,200 astronomical units. The binary system is listed as Σ1341 in the Struve Catalogue of Double Stars; however, this designation is not in wide use and the system is usually referred to by the HD designations of its constituent stars. An extrasolar planet has been confirmed to orbit HD 80606 in a highly elliptical orbit.

    109 Piscium is a yellow hued G-type main-sequence star located about 108 light-years away in the zodiac constellation of Pisces. It is near the lower limit of visibility to the naked eye with an apparent visual magnitude of 6.27. The star is moving closer to the Earth with a heliocentric radial velocity of −45.5 km/s. It has one known exoplanet.

    HD 175541 is an 8th magnitude star with an exoplanetary companion in the constellation Serpens. It has the proper name Kaveh, which was selected by Iran during the NameExoWorlds campaign as part of the 100th anniversary of the IAU. Kaveh is one of the heroes of Shahnameh. The apparent visual magnitude of 8.02 is too faint for this star to be visible in the naked eye. It is located at a distance of approximately 424 light years from the Sun based on parallax measurements, and is drifting further away with a radial velocity of +20 km/s. Despite its distance, it was given the number 736 in the Gliese Catalogue of Nearby Stars.

    HD 185269 is a stellar triple system approximately 170 light-years away in the constellation Cygnus. It is easily visible to binoculars, but not the naked eye.

    HD 192699 is a yellow subgiant star located approximately 214 light-years away in the constellation of Aquila. It has the apparent magnitude of 6.45. Based on its mass of 1.68 solar, it was an A-type star when it was a main-sequence. In April 2007, a planet was announced orbiting the star, together with HD 175541 b and HD 210702 b.

    HD 210702 is an orange subgiant star located approximately 177 light-years away in the constellation of Pegasus. With a mass of 1.8 times that of the Sun, the star spent its main-sequence life as an A-type star. The visual luminosity is 11.38 times that of the Sun and the magnitude is near the naked-eye limit, but binoculars can easily see it.

    Kappa Coronae Borealis b is an extrasolar planet approximately 98 light-years away in the constellation of Corona Borealis. This planet was discovered by Johnson et al., who used the radial velocity method to detect wobbling of the star caused by a planet move around by its tug of gravity. It was first discovered in September 2007 and was published in November.


    HD 192699 b is an exoplanet located approximately 214 light-years away in the constellation of Aquila, orbiting the star HD 192699. This planet was discovered in April 2007, massing at least 2.5 times the mass of Jupiter (MJ). Despite its orbital distance more than that of Earth, the orbital period is less than a year, because the parent star is more massive than the Sun.

    HD 210702 b is an exoplanet located approximately 177 light-years away in the constellation of Pegasus, orbiting the star HD 210702. This planet, together with HD 175541 b and HD 192699 b, are planets around intermediate mass stars that were announced in April 2007 by Johnson et al. It has at least twice the mass of Jupiter and it orbits with semimajor axis of 1.17 AU, corresponding to a period of 341.1 days.

    HD 185269 b is a hot Jupiter extrasolar planet approximately 170 light years away in the constellation of Cygnus. The minimum mass is slightly less than Jupiter and the orbital period is about one week. Most hot Jupiters are thought to have undergone tidal circularization, making the eccentricity of HD 185269 b (e=0.3) unusual. Despite having a large transit probability, none have yet been detected by various photometric monitoring campaigns.

    HD 179079 is a star with an exoplanetary companion in the equatorial constellation of Aquila. It has an apparent visual magnitude of approximately 7.96, making it too faint to be readily visible to the naked eye. The distance to this star can be determine using parallax measurements, which yields an estimate of approximately 228 light years. It is drifting further away with a radial velocity of +20 km/s.

    HD 212771 b is an extrasolar planet orbiting the G-type star HD 212771 approximately 364 light years away in the constellation Aquarius.

    HD 206610 b is an extrasolar planet orbiting the K-type star HD 206610 approximately 633 light years away in the constellation Aquarius.

    HD 181342 b is an extrasolar planet orbiting the K-type star HD 181342 approximately 394 light years away in the constellation Sagittarius.

    <span class="mw-page-title-main">HD 4313 b</span> Extrasolar planet in the constellation Pisces

    HD 4313 b is an extrasolar planet orbiting the K-type star HD 4313 approximately 447 light years away in the constellation Pisces. This planet was discovered using the Doppler spectroscopy method.

    HD 180902 is a binary star approximately 342 light years away in the constellation Sagittarius. The primary is a K-type star while the nature of the secondary is unknown since it has only been detected by its effect on the radial velocity of the primary.

    HD 181342 is a star in the constellation of Sagittarius. With an apparent magnitude of 7.55, it cannot be seen with the naked eye. Parallax measurements made by Gaia spacecraft put the star at a distance of 394 light-years away.

    HD 98219 is a subgiant star in the constellation Crater. It has a confirmed exoplanet. At around 4 billion years old, it is a star around 1.3 times as massive as the Sun that has cooled and expanded to 4.5 times the Sun's diameter, brightening to be around 11 times as luminous. The International Astronomical Union (IAU) gave the opportunity to Honduras to name the star Hunahpú as part of NameExoWorlds. Hunahpú was one of the twin gods who became the Sun in K'iche' (Quiché) Mayan mythology.

    <span class="mw-page-title-main">HD 102956 b</span> Extrasolar planet in the constellation Ursa Major

    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. The system is roughly 399 light years from us.

    HD 212771 is a solitary star in the southern zodiac constellation Aquarius. It has an apparent magnitude of 7.60, making it readily visible with binoculars but not the naked eye. Parallax measurements place the object at a distance of 364 light years, and is currently receding with a radial velocity of 15 km/s.

    References

    1. 1 2 Johnson, John Asher; et al. (2010). "Retired a Stars and Their Companions. IV. Seven Jovian Exoplanets from Keck Observatory". Publications of the Astronomical Society of the Pacific. 122 (892): 701–711. arXiv: 1003.3445 . Bibcode: 2010PASP..122..701J . doi: 10.1086/653809 .
    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. 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.