Astronomy:HD 224693
| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Cetus |
| Right ascension | 23h 59m 53.8316s[1] |
| Declination | −22° 25′ 41.2159″[1] |
| Apparent magnitude (V) | 8.23[2] |
| Characteristics | |
| Spectral type | G2V[3] or G2IV[4] |
| B−V color index | 0.639±0.015[2] |
| Variable type | constant[4] |
| Astrometry | |
| Radial velocity (Rv) | 1.49±0.14[1] km/s |
| Proper motion (μ) | RA: 147.125±0.100[1] mas/yr Dec.: 26.853±0.058[1] mas/yr |
| Parallax (π) | 10.6666 ± 0.0577[1] mas |
| Distance | 306 ± 2 ly (93.8 ± 0.5 pc) |
| Absolute magnitude (MV) | 3.29[2] |
| Details | |
| Mass | 1.29±0.09[5] M☉ |
| Radius | 1.82+0.05 −0.04[1] R☉ |
| Luminosity | 3.78±0.03[1] L☉ |
| Surface gravity (log g) | 4.18±0.06[5] cgs |
| Temperature | 5,971+55 −88[1] K |
| Metallicity [Fe/H] | 0.28±0.02[5] dex |
| Rotational velocity (v sin i) | 4.2[6] km/s |
| Age | 3.0[6] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
| Extrasolar Planets Encyclopaedia | data |
HD 224693, also named Axólotl, is a star in the equatorial constellation of Cetus, and is positioned near the western constellation border with Aquarius. It can be viewed with a small telescope but is too faint to be seen with the naked eye, having an apparent visual magnitude of 8.23.[2] Based on parallax measurements, the object is located at a distance of approximately 306 light years from the Sun. It is drifting further away with a radial velocity of 1.5 km/s.[1]
The star HD 224693 is named Axólotl. The name was selected in the NameExoWorlds campaign by Mexico, during the 100th anniversary of the IAU. "Axólotl" means "water animal" in the native Nahuatl language and an axolotl is also a species of salamander endemic to the valley of Mexico.[7][8]
This is an ordinary G-type main-sequence star with a stellar classification of G2V.[3] However, in 2006, Johnson and associates assigned it a class of G2 IV, suggesting it is instead an evolving subgiant star.[4] It is about three[6] billion years old and chromospherically quiet,[4] with a projected rotational velocity of 4.2 km/s.[6] The star is metal rich, showing a higher abundance of elements other than hydrogen and helium when compared to the Sun.[4] It has 1.3[5] times the mass of the Sun and 1.8 times the Sun's radius. The star is radiating 3.78 times the luminosity of the Sun from its photosphere at an effective temperature of 5,971 K.[1]
Planetary system
In 2006, an extrasolar planet was discovered orbiting HD 224693 by the Keck telescope using radial velocity measurements.[9] A preliminary search for transits using photometric data from Fairborn Observatory was inconclusive because data around the predicted time of transit was too sparse to rule out possible transits.[4] This exoplanet was named Xolotl, after the Aztec god of fire and lightning.[10]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b / Xólotl | ≥0.7±0.12 MJ | 0.191±0.014 | 26.6904±0.0019 | 0.104±0.017 | — | — |
See also
References
- ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 Brown, A. G. A. (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics 616: A1. doi:10.1051/0004-6361/201833051. Bibcode: 2018A&A...616A...1G. Gaia DR2 record for this source at VizieR.
- ↑ 2.0 2.1 2.2 2.3 Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters 38 (5): 331. doi:10.1134/S1063773712050015. Bibcode: 2012AstL...38..331A.
- ↑ 3.0 3.1 Houk, Nancy; Smith-Moore, M. (1978). Michigan catalogue of two-dimensional spectral types for the HD stars. 4. Ann Arbor: Dept. of Astronomy, University of Michigan. Bibcode: 1988mcts.book.....H.
- ↑ 4.0 4.1 4.2 4.3 4.4 4.5 Johnson, John Asher et al. (2006). "The N2K Consortium. VI. Doppler Shifts without Templates and Three New Short-Period Planets". The Astrophysical Journal 647 (1): 600–611. doi:10.1086/505173. Bibcode: 2006ApJ...647..600J.
- ↑ 5.0 5.1 5.2 5.3 Santos, N. C. et al. (2013). "SWEET-Cat: A catalogue of parameters for Stars With ExoplanETs". Astronomy and Astrophysics 556: A150. doi:10.1051/0004-6361/201321286. Bibcode: 2013A&A...556A.150S.
- ↑ 6.0 6.1 6.2 6.3 Delgado Mena, E. et al. (April 2015). "Li abundances in F stars: planets, rotation, and Galactic evolution". Astronomy & Astrophysics 576: 24. doi:10.1051/0004-6361/201425433. A69. Bibcode: 2015A&A...576A..69D.
- ↑ "Approved names" (in en). http://www.nameexoworlds.iau.org/final-results.
- ↑ "100 000s of People from 112 Countries Select Names for Exoplanet Systems In Celebration of IAU's 100th Anniversary". December 17, 2019. https://www.iau.org/news/pressreleases/detail/iau1912/.
- ↑ "Exoplanet-catalog". https://exoplanets.nasa.gov/exoplanet-catalog/6846/hd-224693-b/.
- ↑ Astronomy, Go. "Exoplanet Xolotl | Axolotl star | Cetus Constellation | GO ASTRONOMY" (in en-US). https://www.go-astronomy.com/exoplanet.php?Exo=9.
- ↑ Ment, Kristo et al. (2018). "Radial Velocities from the N2K Project: Six New Cold Gas Giant Planets Orbiting HD 55696, HD 98736, HD 148164, HD 203473, and HD 211810". The Astronomical Journal 156 (5): 213. doi:10.3847/1538-3881/aae1f5. Bibcode: 2018AJ....156..213M.
External links
- "Notes for star HD 224693". Extrasolar Planets Encyclopaedia. http://exoplanet.eu/star.php?st=HD+224693.
Coordinates: 
23h 59m 53.8329s, −22° 25′ 41.208″
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