HD 168746

Last updated
HD 168746 / Alasia
Observation data
Epoch J2000       Equinox J2000
Constellation Serpens
Right ascension 18h 21m 49.7827s [1]
Declination −11° 55 21.652 [1]
Apparent magnitude  (V)7.95 [2]
Characteristics
Spectral type G5V [2]
B−V color index 0.713 [2]
Astrometry
Radial velocity (Rv)−25.606±0.0003 [1]  km/s
Proper motion (μ)RA: −22.946±0.054 [1]   mas/yr
Dec.: −68.402±0.040 [1]   mas/yr
Parallax (π)24.0282 ± 0.0573  mas [1]
Distance 135.7 ± 0.3  ly
(41.62 ± 0.10  pc)
Absolute magnitude  (MV)4.78 [2]
Details [2]
Mass 0.88±0.01  M
Luminosity 1.10  L
Surface gravity (log g)4.50±0.15  cgs
Temperature 5610±30  K
Metallicity [Fe/H]−0.06±0.05  dex
Rotational velocity (v sin i)1.0 km/s
Other designations
Alasia, BD-11° 4606, HIP 90004 [3]
Database references
SIMBAD data
Exoplanet Archive data

HD 168746 is an 8th magnitude star in the constellation of Serpens. It is very similar to the Sun, a yellow dwarf star (spectral class G5V). It is not visible to the unaided eye, but is easily visible with binoculars or a small telescope. In 2000 a planet was announced orbiting it. [4]

Contents

In 2019 the HD 168746 planetary system was chosen as part of the NameExoWorlds campaign organised by the International Astronomical Union to mark to 100th anniversary of the organisation. Each country was assigned a star and planet to be named with HD 168746 being assigned to Cyprus. The winning proposal named the star Alasia, an ancient name for Cyprus, and the planet Onasilos after an ancient Cypriot physician identified in the Idalion Tablet, one of the oldest known legal contracts.

Planetary system

The planet HD 168746 b was discovered by Exoplanet group at the Geneva Observatory with the radial velocity method using the CORALIE spectrograph on the Swiss 1.2-metre Leonard Euler Telescope. [2] At the time it was one of the lowest mass planets that had been discovered.

The HD 168746 planetary system [2]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b (Onasilos)>0.23  MJ 0.0656.403 ± 0.0010.081 ± 0.029

See also

Related Research Articles

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<span class="mw-page-title-main">HD 192263</span> Star in the constellation Aquila

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HD 111232 is a star in the southern constellation of Musca. It is too faint to be visible with the naked eye, having an apparent visual magnitude of 7.59. The distance to this star is 94.5 light years based on parallax. It is drifting away from the Sun with a radial velocity of +104 km/s, having come to within 14.1 light-years some 264,700 years ago. The absolute magnitude of this star is 5.25, indicating it would have been visible to the naked eye at that time.

HD 141937 is a star in the southern zodiac constellation of Libra, positioned a couple of degrees to the north of Lambda Librae. It is a yellow-hued star with an apparent visual magnitude of 7.25, which means it is too faint to be seen with the naked eye. This object is located at a distance of 108.9 light years from the Sun based on parallax, but is drifting closer with a radial velocity of −2.2 km/s. It has an absolute magnitude of 4.71.

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<span class="mw-page-title-main">HD 108147 b</span> Exoplanet in the constellation Crux

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HD 65216 b is an extrasolar planet located approximately 115 light-years away in the constellation of Carina, orbiting the star HD 65216. This planet was discovered by the Geneva Extrasolar Planet Search Team in 2003. Like most planet candidates so far, it was detected with the radial velocity method.

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References

  1. 1 2 3 4 5 6 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.
  2. 1 2 3 4 5 6 7 Pepe, F.; et al. (2002). "The CORALIE survey for southern extra-solar planets VII. Two short-period Saturnian companions to HD 108147 and HD 168746". Astronomy and Astrophysics. 388 (2): 632–638. arXiv: astro-ph/0202457 . Bibcode:2002A&A...388..632P. doi:10.1051/0004-6361:20020433. S2CID   13942987.
  3. "HD 168746". SIMBAD . Centre de données astronomiques de Strasbourg . Retrieved 2018-04-05.
  4. "Exoplanets Galore!" (Press release). Garching, Germany: European Southern Observatory. April 15, 2000. Retrieved December 30, 2012.