HD 17156, named Nushagak by the IAU,[7] is a yellow subgiant star approximately 255 light-years away in the constellation of Cassiopeia. The apparent magnitude is 8.17, which means it is not visible to the naked eye but can be seen with good binoculars.[2] A search for a binary companion star using adaptive optics at the MMT Observatory was negative.[8]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Cassiopeia |
| Right ascension | 02h 49m 44.4867s[1] |
| Declination | +71° 45′ 11.6322″[1] |
| Apparent magnitude (V) | 8.17[2] |
| Characteristics | |
| Spectral type | G0IV[3] |
| Apparent magnitude (B) | 8.76[2] |
| Apparent magnitude (V) | 8.17[2] |
| Astrometry | |
| Radial velocity (Rv) | −3.15 ± 0.20[4] km/s |
| Proper motion (μ) | RA: 90.982±0.064[1] mas/yr Dec.: −33.197±0.062[1] mas/yr |
| Parallax (π) | 12.7776 ± 0.0389 mas[1] |
| Distance | 255.3 ± 0.8 ly (78.3 ± 0.2 pc) |
| Absolute magnitude (MV) | 3.70 |
| Details | |
| Mass | 1.275 ± 0.018[5] M☉ |
| Radius | 1.5007 ± 0.0076[5] R☉ |
| Temperature | 6079 ± 80[6] K |
| Metallicity [Fe/H] | 0.24 ± 0.05[6] dex |
| Age | 3.37 +0.20 −0.47[5] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
The star is more massive and larger than the Sun while Its absolute magnitude of 3.70 and spectral type of G0, show that it is both hotter and more luminous. Based on asteroseismic density constraints and stellar isochrones, it was found that the age is 3.37 +0.20
−0.47 billion years making it about two thirds as old as the Sun. Spectral observations show that the star is metal-rich.[3][5]
An extrasolar planet, HD 17156 b, was discovered with the radial velocity method in 2007, and subsequently was observed to transit the star. At the time it was the transiting planet with the longest period.[3][9]
Name
editThe star was given the name Nushagak by the IAU, chosen by United States representatives for the NameExoWorlds content, with the comment that "Nushagak is a regional river near Dilingham, Alaska, which is famous for its wild salmon that sustain local Indigenous communities."[7] HD 17156 b was given the designation Mulchatna, as Mulchatna is a tributary of the Nushagak river.
Planetary system
editIt is the first star in Cassiopeia around which an orbiting planet was discovered (in 2007) using the radial velocity method. Later observations showed that this planet also transited the star.[9] In February 2008, a second planet was proposed, with a 5:1 mean motion resonance to the inner planet HD 17156 b, though in 2017 this planet candidate was retracted.[10]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b / Mulchatna | 3.235±0.032 MJ | 0.16278±0.00076 | 21.2163979 ± 0.0000159 | 0.6703+0.0014 −0.0013 |
— | — |
See also
editReferences
edit- ^ a b c d e 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.
- ^ a b c d e "HD 17156". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2009-05-20.
- ^ a b c Fischer, Debra A.; et al. (2007). "Five Intermediate-Period Planets from the N2K Sample". The Astrophysical Journal. 669 (2): 1336–1344. arXiv:0704.1191. Bibcode:2007ApJ...669.1336F. doi:10.1086/521869. S2CID 7774321.
- ^ Barbieri, M.; et al. (2009). "Characterization of the HD 17156 planetary system". Astronomy and Astrophysics. 503 (2): 601–612. arXiv:0812.0785. Bibcode:2009A&A...503..601B. doi:10.1051/0004-6361/200811466. S2CID 3762143.
- ^ a b c d e Nutzman, Philip; et al. (2011). "Precise Estimates of the Physical Parameters for the Exoplanet System HD 17156 Enabled by Hubble Space Telescope Fine Guidance Sensor Transit and Asteroseismic Observations". The Astrophysical Journal. 726 (1). 3. arXiv:1011.0440. Bibcode:2011ApJ...726....3N. doi:10.1088/0004-637X/726/1/3. S2CID 118003582.
- ^ a b Winn, Joshua N.; et al. (2009). "The Transit Light Curve Project. X. A Christmas Transit of HD 17156b". The Astrophysical Journal. 693 (1): 794–803. arXiv:0810.4725. Bibcode:2009ApJ...693..794W. doi:10.1088/0004-637X/693/1/794. S2CID 13894861.
- ^ a b "Approved names (§ United States of America)". Name Exo Worlds. IAU. Retrieved 19 December 2019.
- ^ Adams, E. R.; et al. (2013). "Adaptive Optics Images. II. 12 Kepler Objects of Interest and 15 Confirmed Transiting Planets". The Astronomical Journal. 146 (1). 9. arXiv:1305.6548. Bibcode:2013AJ....146....9A. doi:10.1088/0004-6256/146/1/9. S2CID 119117620.
- ^ a b Barbieri, M.; et al. (2007). "HD 17156b: A Transiting Planet with a 21.2 Day Period and an Eccentric Orbit". Astronomy and Astrophysics Letters. 476 (2): L13–L16. arXiv:0710.0898. Bibcode:2007A&A...476L..13B. doi:10.1051/0004-6361:20078787. S2CID 14430349.
- ^ a b Short, Donald; et al. (2008). "Orbital Dynamics Of A Possible Second Planet In HD 17156". arXiv:0803.2935. Bibcode:2008arXiv0803.2935S.
OUTDATED, REJECTED AND CANNOT BE PUBLISHED. DOES NOT INCLUDE VARIOUS ADVANCEMENTS IN THE FIELD (REPORTED IN OTHER PUBLICATIONS). NEED MORE DATA OBTAINED, AT WHICH POINT A COMPLETELY NEW PAPER WILL BE WRITTEN. PLEASE SCRAP
{{cite journal}}: Cite journal requires|journal=(help) - ^ Bonomo, A. S.; et al. (2017). "The GAPS Programme with HARPS-N at TNG . XIV. Investigating giant planet migration history via improved eccentricity and mass determination for 231 transiting planets". Astronomy and Astrophysics. 602. A107. arXiv:1704.00373. Bibcode:2017A&A...602A.107B. doi:10.1051/0004-6361/201629882. S2CID 118923163.
External links
edit- Extrasolar Planet Interactions Archived 2016-05-05 at the Wayback Machine by Rory Barnes & Richard Greenberg, Lunar and Planetary Lab, University of Arizona
- "HD 17156". Exoplanets. Archived from the original on 2012-04-01. Retrieved 2009-05-20.