HD 195564
Star in the constellation Capricornus / From Wikipedia, the free encyclopedia
HD 195564 is the Henry Draper Catalogue designation for a star in the southern constellation of Capricornus. It is faintly visible to the naked eye with an apparent visual magnitude of 5.65.[2] Parallax measurements give us an estimate of its distance as 81 light years. This is a candidate wide binary system as a faint companion star shares a common proper motion with the brighter primary component.[7]
Observation data Epoch J2000.0 Equinox J2000.0 | |
---|---|
Constellation | Capricornus |
Right ascension | 20h 32m 23.695s[1] |
Declination | −09° 51′ 12.18″[1] |
Apparent magnitude (V) | 5.65[2] |
Characteristics | |
Spectral type | G2 V[3] |
U−B color index | +0.20[2] |
B−V color index | +0.68[2] |
Astrometry | |
Radial velocity (Rv) | +9.58[4] km/s |
Proper motion (μ) | RA: +309.736 mas/yr[1] Dec.: +109.910 mas/yr[1] |
Parallax (π) | 40.4241 ± 0.0497 mas[1] |
Distance | 80.68 ± 0.10 ly (24.74 ± 0.03 pc) |
Details | |
HD 195564 A | |
Mass | 1.097[5] M☉ |
Radius | 1.867±0.083[5] R☉ |
Luminosity | 2.705±0.047[5] L☉ |
Surface gravity (log g) | 3.74[3] cgs |
Temperature | 5421±118[5] K |
Metallicity [Fe/H] | +0.06[5] dex |
Rotational velocity (v sin i) | 1.91[6] km/s |
Age | 8.2[5] Gyr |
HD 195564 B | |
Mass | 0.55[7] M☉ |
Other designations | |
Database references | |
SIMBAD | data |
ARICNS | data |
Based upon the spectrum of light emitted by the primary, it has a stellar classification of G2 V.[3] This indicates that it is a G-type main sequence star that is generating energy through the process of thermonuclear fusion in its core region. It has an estimated mass of 1.097[5] times the mass of the Sun, but a measured radius that is 1.867 times as large.[5] As a result, it shines with 2.705 times the luminosity of the Sun.[5] The abundance of elements in this star is similar to that in the Sun, although it is an older star with an age of around 8.2 billion years.[5] The effective temperature of the stellar atmosphere is 5,421 K,[5] giving it the yellow-hued glow of an ordinary K-type star.[9]
The secondary companion has an apparent magnitude of 11.30,[10] and a mass just 55% that of the Sun.[7] As measured in 1965, it had an angular separation of 3.20″ from the primary, along a position angle of 27°[10] The pair orbit each other with an estimated period of around 510 years.[7]
In a paper published in April 2017, a candidate planet was found orbiting HD 195564 with a period of 5,404 days (14.80 yr).[11]
Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
---|---|---|---|---|---|---|
b (unconfirmed) | — | — | 5403.77251±164.1426 | — | — | — |