| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Pisces |
| Right ascension | 00h 44m 41.2003s[1] |
| Declination | +20° 26′ 56.1380″[1] |
| Apparent magnitude (V) | 8.70[2] |
| Characteristics | |
| Spectral type | G5V[3] |
| B−V color index | +0.771±0.021[2] |
| Astrometry | |
| Radial velocity (Rv) | −14.20±0.09[2] km/s |
| Proper motion (μ) | RA: +122.070±0.102[1] mas/yr Dec.: −124.192±0.062[1] mas/yr |
| Parallax (π) | 12.2595 ± 0.0538 mas[1] |
| Distance | 266 ± 1 ly (81.6 ± 0.4 pc) |
| Absolute magnitude (MV) | 4.28[2] |
| Details[4] | |
| Mass | 1.12±0.03 M☉ |
| Radius | 1.35±0.03 R☉ |
| Luminosity | 1.68±0.01 L☉ |
| Surface gravity (log g) | 4.22±0.03 cgs |
| Temperature | 5,666±43 K |
| Metallicity [Fe/H] | 0.34±0.01[2] dex |
| Rotational velocity (v sin i) | 5.6[5] km/s |
| Age | 6.3±1.0 Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
HD 4203 is a single star in the equatorial constellation of Pisces, near the northern constellation border with Andromeda. It has a yellow hue and is too faint to be viewed with the naked eye, having an apparent visual magnitude of 8.70.[2] The distance to this object is 266 light years based on parallax,[1] but it is drifting closer to the Sun with a radial velocity of −14 km/s.[2]
This object is an ordinary G-type main-sequence star with a stellar classification of G5V. It is photometrically-stable star with an inactive chromosphere, and has a much higher than normal metallicity.[3] The star is roughly 6.3 billion years old and is spinning with a projected rotational velocity of 5.6 km/s.[5] It has 12% more mass than the Sun and a 35% greater radius. HD 4203 is radiating 1.68 times the luminosity of the Sun from its photosphere at an effective temperature of 5,666 K.[4]
Planetary system
[edit]Radial velocity observations of this star during 2000–2001 found a variability that suggesting an orbited sub-stellar companion, designated component 'b'.[3] Additional observations led to a refined orbital period of 432 days with a relatively high eccentricity of 0.52 for a gas giant companion.[7] The presence of a second companion was deduced from residuals in the data, then confirmed in 2014. However, the orbital elements for this companion, component 'c', are poorly constrained.[8]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | > 1.164±0.067 MJ | 2.07±0.18 | 431.88±0.85 | 0.519±0.027 | — | — |
| c | > 2.17±0.52 MJ | — | 6,700±4,500 | 0.24±0.13 | — | — |
See also
[edit]Notes
[edit]- ^ a b c d e f 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 f g Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. S2CID 119257644.
- ^ a b c Vogt, Steven S.; et al. (2002). "Ten Low-Mass Companions from the Keck Precision Velocity Survey". The Astrophysical Journal. 568 (1): 352–362. arXiv:astro-ph/0110378. Bibcode:2002ApJ...568..352V. doi:10.1086/338768. S2CID 2272917.
- ^ a b Bonfanti, A.; et al. (2015). "Revising the ages of planet-hosting stars". Astronomy and Astrophysics. 575. A18. arXiv:1411.4302. Bibcode:2015A&A...575A..18B. doi:10.1051/0004-6361/201424951. S2CID 54555839.
- ^ a b Luck, R. Earle (January 2017). "Abundances in the Local Region II: F, G, and K Dwarfs and Subgiants". The Astronomical Journal. 153 (1): 19. arXiv:1611.02897. Bibcode:2017AJ....153...21L. doi:10.3847/1538-3881/153/1/21. S2CID 119511744. 21.
- ^ "HD 4203". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 4 November 2019.
- ^ a b Butler, R. P.; et al. (2006). "Catalog of Nearby Exoplanets". The Astrophysical Journal. 646 (1): 505–522. arXiv:astro-ph/0607493. Bibcode:2006ApJ...646..505B. doi:10.1086/504701. S2CID 119067572.
- ^ Kane, Stephen R.; et al. (April 2014). "Limits on Stellar Companions to Exoplanet Host Stars with Eccentric Planets". The Astrophysical Journal. 785 (2): 10. arXiv:1401.1544. Bibcode:2014ApJ...785...93K. doi:10.1088/0004-637X/785/2/93. S2CID 2053475. 93.
External links
[edit]
Well, that’s interesting to know that Psilotum nudum are known as whisk ferns. Psilotum nudum is the commoner species of the two. While the P. flaccidum is a rare species and is found in the tropical islands. Both the species are usually epiphytic in habit and grow upon tree ferns. These species may also be terrestrial and grow in humus or in the crevices of the rocks.
View the detailed Guide of Psilotum nudum: Detailed Study Of Psilotum Nudum (Whisk Fern), Classification, Anatomy, Reproduction