HD 1502 (proper name Citadelle) is an 8th-magnitude K-type subgiant star in the constellation of Pisces, located at a distance of approximately 630 light-years. A super-Jupiter planet, HD 1502 b (proper name Indépendance), is known to orbit the star.

HD 1502 / Citadelle
Location of HD 1502 (circled)
Observation data
Epoch J2000.0[1]      Equinox J2000.0[1]
Constellation Pisces
Right ascension 00h 19m 17.0663772928s[1]
Declination +14° 03′ 17.121365380″[1]
Apparent magnitude (V) 8.36[2]
Characteristics
Spectral type K0 IV[2][3][4]
B−V color index 0.92[2]
Astrometry
Radial velocity (Rv)−9.81[1] km/s
Proper motion (μ) RA: 74.113[1] mas/yr
Dec.: −16.945[1] mas/yr
Parallax (π)5.2095 ± 0.0753 mas[1]
Distance626 ± 9 ly
(192 ± 3 pc)
Details
Mass1.46±0.15[4] M
Radius4.67±0.57[4] R
Luminosity11.75+15.14
−9.12
[4] L
Surface gravity (log g)3.18[4] cgs
Temperature4947[4] K
Metallicity [Fe/H]0.09±0.03[2] dex
Rotational velocity (v sin i)2.70±0.5[2] km/s
Age3.0+1.2
−0.8
[4] Gyr
Other designations
BD+13°34, Gaia DR2 2768172019308167296, HD 1502, HIP 1547, SAO 91845, TYC 601-636-1, GSC 00601-00636, 2MASS J00191704+1403172[1]
Database references
SIMBADdata

Nomenclature

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In 2019, the Republic of Haiti was assigned to giving the HD 1502 system a proper name as part of the IAU100 NameExoWorlds Project, planned to celebrate the hundredth anniversary of the International Astronomical Union (IAU), which grants the right to name an exoplanetary system to every state and territory in the world.[5] Names were submitted and selected within Haiti, which were then presented to the IAU to be officially recognized.[6] On 17 December 2019, the IAU announced that HD 1502 and its planet, b, were named Citadelle and Indépendance, respectively.[7]

Citadelle refers to the Citadelle Laferrière, a fortress located in Milot in northern Haiti, which was built in 1820 and declared a world heritage site in 1982 as part of the National History Park. Indépendance was named after the Haitian Declaration of Independence, in celebration of the country's independence on 1 January 1804.[7]

Stellar characteristics

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The star has evolved past the main sequence stage and is now a subgiant with a mass of 1.46 M, a radius of 4.67 R, and a spectral type of K0.[2][3][4] The star is slightly richer than the Sun in elements heavier than hydrogen and helium, with a metallicity of 0.09 ± 0.03.[a][2]

The star has an effective temperature of 4,947 K (4,674 °C; 8,445 °F),[4] making it cooler than the Sun (5,772 K).[8] Despite this, its large size makes it roughly 12 times brighter.[4] At around 3.0 billion years old,[4] the star is about two-thirds the age of the Sun (4.6 Gyr).[9] Due to its high mass, however, it is further evolved than the Sun, which will spend a total of 10 billion years as a main sequence star.[10]

Planetary system

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In 2011, an exoplanet orbiting HD 1502, designated HD 1502 b, was discovered using the radial-velocity method.[2] HD 1502 b revolves around its host star at a distance of 1.262 AU (188,800,000 km) with a period of little over one year in a near-circular orbit (i.e., with a low eccentricity),[3] similarly to planets in the Solar System.[11] It is a super-Jupiter planet with a minimum mass of 2.75 MJ and a predicted radius of 1.183 RJ.[3]

The HD 1502 planetary system[3]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b (Indépendance) ≥2.75 ± 0.16 MJ 1.262 ± 0.092 428.5 ± 1.2 0.031 ± 0.022 1.183 (predicted)  RJ

See also

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References

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  1. ^ a b c d e f g h "Results for HD 1502". SIMBAD Astronomical Database. Observatory of Strasbourg. Retrieved 2019-07-17.
  2. ^ a b c d e f g h Johnson, John Asher; et al. (2011). "Retired A Stars and Their Companions. VII. 18 New Jovian Planets". The Astrophysical Journal Supplement Series. 197 (2): 26. arXiv:1108.4205. Bibcode:2011ApJS..197...26J. doi:10.1088/0067-0049/197/2/26. ISSN 0067-0049.
  3. ^ a b c d e 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. ISSN 1538-3881.
  4. ^ a b c d e f g h i j k Brewer, John M.; Fischer, Debra A.; Valenti, Jeff A.; Piskunov, Nikolai (2016). "Spectral Properties of Cool Stars: Extended Abundance Analysis of 1,617 Planet-search Stars". The Astrophysical Journal Supplement Series. 225 (2): 32. arXiv:1606.07929. Bibcode:2016ApJS..225...32B. doi:10.3847/0067-0049/225/2/32. ISSN 1538-4365.
  5. ^ "List of stars and planets | IAU100 Name ExoWorlds - An IAU100 Global Event". Name Exoworlds. International Astronomical Union. Retrieved 2019-07-17.
  6. ^ "Methodology | IAU100 Name ExoWorlds - An IAU100 Global Event". Name Exoworlds. International Astronomical Union. Retrieved 2019-07-17.
  7. ^ a b "Haiti | NameExoworlds". Name Exoworlds. International Astronomical Union. 2019-12-17. Retrieved 2020-01-26.
  8. ^ Williams, D. R. (1 July 2013). "Sun Fact Sheet". NASA Goddard Space Flight Center. Archived from the original on 15 July 2010. Retrieved 12 August 2013.
  9. ^ Connelly, J. N.; Bizzarro, M.; Krot, A. N.; Nordlund, Å.; Wielandt, D.; Ivanova, M. A. (2 November 2012). "The Absolute Chronology and Thermal Processing of Solids in the Solar Protoplanetary Disk". Science. 338 (6107): 651–655. Bibcode:2012Sci...338..651C. doi:10.1126/science.1226919. PMID 23118187. S2CID 21965292.(registration required)
  10. ^ "Main Sequence Stars". Australia Telescope National Facility. Retrieved 2024-07-17.
  11. ^ Limbach, MA; Turner, EL (2015). "Exoplanet orbital eccentricity: multiplicity relation and the Solar System". Proc Natl Acad Sci U S A. 112 (1): 20–4. arXiv:1404.2552. Bibcode:2015PNAS..112...20L. doi:10.1073/pnas.1406545111. PMC 4291657. PMID 25512527.

Footnotes

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  1. ^ This translates to an abundance of iron 100.09≈1.23 times that of the Sun. The margin of error (0.06–0.12) corresponds to a comparative abundance of 115–132% (100.06–100.12).

Further reading

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