HD 70642

Last updated
HD 70642
Observation data
Epoch J2000.0       Equinox J2000.0
Constellation Puppis
Right ascension 08h 21m 28.13685s [1]
Declination −39° 42 19.4843 [1]
Apparent magnitude  (V)+7.17 [2]
Characteristics
Spectral type G6V CN+0.5 [3]
B−V color index 0.692±0.022 [2]
Astrometry
Radial velocity (Rv)+49.31±0.12 [1] km/s
Proper motion (μ)RA: −201.729 mas/yr [1]
Dec.: 225.102 mas/yr [1]
Parallax (π)34.1478±0.0154  mas [1]
Distance 95.51 ± 0.04  ly
(29.28 ± 0.01  pc)
Absolute magnitude  (MV)+4.93 [2]
Details
Mass 1.04±0.02 [4]   M
Radius 0.97±0.01 [4]   R
Luminosity 0.917±0.004 [4]   L
Surface gravity (log g)4.47±0.02 [4]   cgs
Temperature 5732±23 [4]   K
Metallicity [Fe/H]+0.17±0.04 [5]   dex
Rotational velocity (v sin i)1.57 [6]  km/s
Age 1.9±1.1 Gyr [4]
3.8±2.6 [6]   Gyr
Other designations
CD−39°4247, GJ  304, HD  70642, HIP  40952, SAO  199126, LTT  3116 [7]
Database references
SIMBAD data
Exoplanet Archive data
ARICNS data

HD 70642 is a star with an exoplanetary companion in the southern constellation of Puppis. It has an apparent visual magnitude of +7.17, [2] which is too dim to be readily visible to the naked eye. The system is located at a distance of 95.5 light-years (29.3 parsecs ) from the Sun based on parallax measurements, and is drifting further away with a radial velocity of +49.3 km/s. [1] It came to within 55.3 ly of the Solar System some 329,000 years ago. [2]

Contents

This may be considered to be a solar analog star, being similar in physical properties to the Sun. [5] It is a G-type main-sequence star with a stellar classification of G6V CN+0.5. [3] It is comparable to the age of the Sun, estimated to be in the range of 2–6 billion years old. Although chromospherically inactive a magnetic field has been detected. [5] This star has about the same mass and radius as the Sun, is slightly cooler and less luminous, [4] and is richer in abundance of iron relative to hydrogen. [5] It is spinning at a leisurely rate, showing a projected rotational velocity of 1.6 km/s. [6]

Planetary system

A long period planetary companion to HD 70642 was announced in 2003. This planet orbits in a circular orbit (e=0.034) at 3.232 AU. [8] HD 70642 itself is similar enough to the sun that its habitable zone is at around the same distance(0.9-1.3 AU). HD 70642 b is thought to be compatible with potential Earth-mass planets at 1 AU. Because of this the HD 70642 system may be similar in structure to our own. [9] In 2023, the inclination and true mass of HD 70642 b were determined via astrometry. [10]

The HD 70642 planetary system [10]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(years)
Eccentricity Inclination Radius
b 3.9+0.29
−0.27
  MJ
3.295±0.0215.751+0.038
−0.035
0.04+0.034
−0.027
29.9+2.6
−2.4
or 150.1+2.4
−2.6
°

See also

References