Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Sculptor |
Right ascension | 00h 53m 00.71555s [1] |
Declination | −30° 21′ 25.1677″ [1] |
Apparent magnitude (V) | +7.3029 [1] |
Characteristics | |
Spectral type | K2.5 V (k) [2] |
B−V color index | 0.936 [1] |
Astrometry | |
Radial velocity (Rv) | −13.021±0.0064 [3] km/s |
Proper motion (μ) |
RA: +620.35
[1]
mas/
yr Dec.: +30.26 [1] mas/ yr |
Parallax (π) | 71.5472 ± 0.0573 mas [4] |
Distance | 45.59 ± 0.04
ly (13.98 ± 0.01 pc) |
Absolute magnitude (MV) | +6.39 [5] |
Details | |
Radius | 0.660 [6] R☉ |
Luminosity | 0.29 [5] L☉ |
Surface gravity (log g) | 4.55 [2] cgs |
Temperature | 4,822 [2] K |
Metallicity [Fe/H] | −0.21 [2] dex |
Rotational velocity (v sin i) | 1.8 [7] km/s |
Age | 6.67±4.74 [8] Gyr |
Other designations | |
Database references | |
SIMBAD | data |
Gliese 42 is a star in the southern constellation of Sculptor. It is too faint to be seen with the naked eye, having an apparent visual magnitude of +7.3. [1] The annual parallax shift of 70.56 mas provides a distance estimate of 46 light years. It has a relatively high proper motion, advancing 0.62 [10] arcseconds across the sky per annum, and is moving closer to the Sun with a radial velocity of −13 km/s. [3]
The spectrum of the star matches a stellar classification of K2.5 V (k), [2] indicating it is an ordinary K-type main-sequence star that is generating energy through hydrogen fusion at its core. It is radiating 29% [5] of the Sun's luminosity from its photosphere at an effective temperature of 4,822 K. [2] The star has 66% [6] of the Sun's radius.
An infrared excess has been detected around this star, [11] most likely indicating the presence of a circumstellar disk at a radius of 45.7 astronomical units (6.84×109 km; 4.25×109 mi). The temperature of this dust was initially estimated as 30 K (−243.2 °C; −405.7 °F) [6] according to measurement by Herschel Space Observatory. Later that measurement was deemed questionable, [12] and fixed temperature of 62 K (−211.2 °C; −348.1 °F) was obtained in 2020. [13]
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Sculptor |
Right ascension | 00h 53m 00.71555s [1] |
Declination | −30° 21′ 25.1677″ [1] |
Apparent magnitude (V) | +7.3029 [1] |
Characteristics | |
Spectral type | K2.5 V (k) [2] |
B−V color index | 0.936 [1] |
Astrometry | |
Radial velocity (Rv) | −13.021±0.0064 [3] km/s |
Proper motion (μ) |
RA: +620.35
[1]
mas/
yr Dec.: +30.26 [1] mas/ yr |
Parallax (π) | 71.5472 ± 0.0573 mas [4] |
Distance | 45.59 ± 0.04
ly (13.98 ± 0.01 pc) |
Absolute magnitude (MV) | +6.39 [5] |
Details | |
Radius | 0.660 [6] R☉ |
Luminosity | 0.29 [5] L☉ |
Surface gravity (log g) | 4.55 [2] cgs |
Temperature | 4,822 [2] K |
Metallicity [Fe/H] | −0.21 [2] dex |
Rotational velocity (v sin i) | 1.8 [7] km/s |
Age | 6.67±4.74 [8] Gyr |
Other designations | |
Database references | |
SIMBAD | data |
Gliese 42 is a star in the southern constellation of Sculptor. It is too faint to be seen with the naked eye, having an apparent visual magnitude of +7.3. [1] The annual parallax shift of 70.56 mas provides a distance estimate of 46 light years. It has a relatively high proper motion, advancing 0.62 [10] arcseconds across the sky per annum, and is moving closer to the Sun with a radial velocity of −13 km/s. [3]
The spectrum of the star matches a stellar classification of K2.5 V (k), [2] indicating it is an ordinary K-type main-sequence star that is generating energy through hydrogen fusion at its core. It is radiating 29% [5] of the Sun's luminosity from its photosphere at an effective temperature of 4,822 K. [2] The star has 66% [6] of the Sun's radius.
An infrared excess has been detected around this star, [11] most likely indicating the presence of a circumstellar disk at a radius of 45.7 astronomical units (6.84×109 km; 4.25×109 mi). The temperature of this dust was initially estimated as 30 K (−243.2 °C; −405.7 °F) [6] according to measurement by Herschel Space Observatory. Later that measurement was deemed questionable, [12] and fixed temperature of 62 K (−211.2 °C; −348.1 °F) was obtained in 2020. [13]