| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Circinus [1] |
| Right ascension | 15h 10m 44.74301s [2] |
| Declination | −61° 25′ 20.3607″ [2] |
| Apparent magnitude (V) | 6.29±0.01 [3] |
| Characteristics | |
| Evolutionary stage | main sequence or subgiant [2] |
| Spectral type | G0 V Fe+0.4 [4] or G3 IV [3] |
| B−V color index | 0.623±0.003 [1] |
| Astrometry | |
| Radial velocity (Rv) | 43.50±0.74 [1] km/s |
| Proper motion (μ) | RA: −185.606 [2] mas/yr Dec.: −12.142 [2] mas/yr |
| Parallax (π) | 41.6198±0.0202 mas [2] |
| Distance | 78.37 ± 0.04 ly (24.03 ± 0.01 pc) |
| Absolute magnitude (MV) | 4.37 [1] |
| Details [3] | |
| Mass | 1.07±0.07 M☉ |
| Radius | 1.15±0.02 R☉ |
| Luminosity | 1.63 [1] L☉ |
| Surface gravity (log g) | 4.35±0.04 cgs |
| Temperature | 5,965±50 K |
| Metallicity [Fe/H] | +0.14±0.01 dex |
| Rotation | 21.2±1.1 d [5] |
| Rotational velocity (v sin i) | 3.21 [6] km/s |
| Age | 1.75 [6] Gyr |
| Other designations | |
| 38 G. Circini, CD−60°5490, HD 134060, HIP 74273, HR 5632, SAO 253043, LTT 6035 [7] | |
| Database references | |
| SIMBAD | data |
HD 134060, also known by its Gould designation of 38 G. Circini, is a star in the southern constellation of Circinus. It is near the lower limit of stars visible to the naked eye, having an apparent visual magnitude of 6.29. [3] The distance to HD 134060, as determined using an annual parallax shift measurement of 41.6 mas , [2] is 78.4 light years. It is moving further away with a heliocentric radial velocity of 43.5 km/s, having come within 34.6 ly some 439,000 years ago. [1]
During the NStars project, Grey et al. (2006) found a stellar classification of G0 V Fe+0.4 for this star, [4] matching a Sun-like G-type main-sequence star with an overabundance of iron in its outer atmosphere. However, an older classification of G3 IV [3] is still used, which would suggest it is instead a more evolved subgiant star. HD 134060 has an estimated 1.07 times the mass of the Sun and 1.15 times the Sun's radius. [3] It is radiating 1.63 [1] times the Sun's luminosity from its photosphere at an effective temperature of about 5,965 K . [3]
The survey in 2015 have ruled out the existence of any additional stellar companions at projected distances from 22 to 163 astronomical units. [8]
Based upon an 8-year survey using the HARPS spectrograph at La Silla Observatory, in 2011 the detection of a pair of planets orbiting this star were announced. The inner planet, HD 134060 b, is in a tight, eccentric orbit around the star with a period of just over three days. The second object, HD 134060 c, has a more leisurely period of around 3.2 years and a high orbital eccentricity. [9]
The star was observed for a few hours by the Spitzer Space Telescope in the hopes of observing a transit by the inner planet, but none was detected. [3] HD 134060 displays an infrared excess at a wavelength of 18μm, making it a warm debris disk candidate. [10]
| Companion (in order from star) | Mass | Semimajor axis (AU) | Orbital period (days) | Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | 0.0351±0.0021 MJ | 0.0441±0.0010 [6] | 3.269555+0.000092 −0.000080 [6] | 0.480±0.034 [6] | — | — |
| c | 0.1507±0.071 MJ | 2.2263±0.0507 | 1,160.9±27.046 | 0.75±0.19 | — | — |