Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Piscis Austrinus |
Right ascension | 23h 05m 52.03604s [1] |
Declination | −35° 51′ 11.0475″ [1] |
Apparent magnitude (V) | 7.34 [2] |
Characteristics | |
Spectral type | M0.5V [3] |
U−B color index | +1.18 [2] |
B−V color index | +1.50 [2] |
Variable type | Suspected [4] |
Astrometry | |
Radial velocity (Rv) | +9.7 [5] km/s |
Proper motion (μ) | RA: +6,765.995 [6] mas/yr Dec.: +1,330.388 [6] mas/yr |
Parallax (π) | 304.1354 ± 0.0200 mas [7] |
Distance | 10.7241 ± 0.0007 ly (3.2880 ± 0.0002 pc) |
Absolute magnitude (MV) | 9.8 [8] |
Details | |
Mass | 0.479+0.011 −0.010 [9] M☉ |
Radius | 0.474±0.008 [9] R☉ |
Luminosity | 0.0368±0.0006 [9] L☉ |
Surface gravity (log g) | 4.78 [10] cgs |
Temperature | 3,672+36 −34 [9] K |
Metallicity [Fe/H] | −0.22±0.09 [11] dex |
Rotational velocity (v sin i) | 1 [5] km/s |
Age | 4.57 [12] Gyr |
Other designations | |
Database references | |
SIMBAD | data |
ARICNS | data |
Location of Lacaille 9352 in the constellation Piscis Austrinus |
Lacaille 9352 (Lac 9352) is a red dwarf star in the southern constellation of Piscis Austrinus. With an apparent visual magnitude of 7.34, [2] this star is too faint to be viewed with the naked eye except possibly under excellent seeing conditions. Parallax measurements place it at a distance of about 10.74 light-years (3.29 parsecs ) from Earth. [1] It is the eleventh closest star system to the Solar System [14] and is the closest star in the constellation Piscis Austrinus. The ChView simulation [15] shows that its closest neighbour is the EZ Aquarii triple star system at about 4.1 ly away.
This star has the fourth highest known proper motion, [16] (which was first noticed by Benjamin Gould in 1881 [17] ) moving a total of 6.9 arcseconds per year. However, this is still a very small movement overall, as there are 3,600 arcseconds in a degree of arc. The space velocity components of this star are (U, V, W) = (−93.9, −14.1, −51.4) km/s. [18] If the radial velocity (Vr) equals +9.7 km/s then about 2,700 years ago Lacaille 9352 was at its minimal distance of approximately 10.63 ly (3.26 pc) from the Sun. [19]
The spectrum of Lacaille 9352 places it at a stellar classification of M0.5V, [3] indicating it is a type of main sequence star known as a red dwarf. This was the first red dwarf star to have its angular diameter measured, [20] with the physical diameter being about 47% of the Sun's radius. [9] It has around half the mass of the Sun [3] and the outer envelope has an effective temperature of about 3,670 K. [9]
In June 2020, two super-Earth planets were reported, as well as a third signal with a period of 50.7 days that may be due to stellar activity—however, if this planet is real it may be located within the habitable zone. They were detected using the radial velocity method from observations with HARPS in Chile and HIRES in Hawaii. [21] [22]
Companion (in order from star) | Mass | Semimajor axis (AU) | Orbital period (days) | Eccentricity | Inclination | Radius |
---|---|---|---|---|---|---|
b | ≥ 4.2±0.6 M🜨 | 0.068±0.002 | 9.262±0.001 | 0.09+0.09 −0.06 | — | — |
c | ≥ 7.6±1.2 M🜨 | 0.120±0.004 | 21.789+0.004 −0.005 | 0.22+0.09 −0.10 | — | — |
d(unconfirmed) | ≳ 8.3 M🜨 | ~0.21 | ~50.7 | 0.25+0.20 −0.15 | — | — |
Microscopium is a minor constellation in the southern celestial hemisphere, one of twelve created in the 18th century by French astronomer Nicolas-Louis de Lacaille and one of several depicting scientific instruments. The name is a Latinised form of the Greek word for microscope. Its stars are faint and hardly visible from most of the non-tropical Northern Hemisphere.
Piscis Austrinus is a constellation in the southern celestial hemisphere. The name is Latin for "the southern fish", in contrast with the larger constellation Pisces, which represents a pair of fish. Before the 20th century, it was also known as Piscis Notius. Piscis Austrinus was one of the 48 constellations listed by the 2nd-century astronomer Ptolemy, and it remains one of the 88 modern constellations. The stars of the modern constellation Grus once formed the "tail" of Piscis Austrinus. In 1597, Petrus Plancius carved out a separate constellation and named it after the crane.
Delta Aquarii, officially named Skat, is the third-brightest star in the constellation of Aquarius. The apparent visual magnitude is 3.3, which can be seen with the naked eye. The distance to this star is about 113 light-years based upon parallax measurements, and it has a close companion.
Groombridge 34 is a binary star system in the northern constellation of Andromeda. It was listed as entry number 34 in A Catalogue of Circumpolar Stars, published posthumously in 1838 by British astronomer Stephen Groombridge. Based upon parallax measurements taken by the Gaia spacecraft, the system is located about 11.6 light-years from the Sun. This positions the pair among the nearest stars to the Solar System.
Lacaille 8760 is a red dwarf star in the constellation Microscopium. It is one of the nearest stars to the Sun at about 12.9 light-years' distance, and the brightest M-class main-sequence star in Earth's night sky, although it is generally too faint to be seen without a telescope. At an apparent magnitude of +6.7, it may only be visible to the unaided eye under exceptionally good viewing conditions, under dark skies.
HD 142 is a wide binary star system in the southern constellation of Phoenix. The main component has a yellow-white hue and is dimly visible to the naked eye with an apparent visual magnitude of 5.7. The system is located at a distance of 85.5 light years from the Sun based on parallax measurements, and is drifting further away with a radial velocity of +6 km/s.
HD 222582 is a multiple star system in the equatorial constellation of Aquarius. It is invisible to the naked eye with an apparent visual magnitude of 7.7, but can be viewed with binoculars or a small telescope. The system is located at a distance of 137 light years from the Sun based on parallax, and it is drifting further away with a radial velocity of +12 km/s. It is located close enough to the ecliptic that it is subject to lunar occultations.
IC 2391 is an open cluster in the constellation Vela consisting of hot, young, blueish stars, some of which binaries and one of which is a quadruple. Persian astronomer A. a.-R. al-Sufi first described it as "a nebulous star" in c. 964. It was re-found by Abbe Lacaille and cataloged as Lac II 5.
36 Ursae Majoris is a double star in the northern constellation of Ursa Major. With an apparent visual magnitude of 4.8, it can be seen with the naked eye in suitable dark skies. Based upon parallax measurements, this binary lies at a distance of 42 light-years from Earth.
Delta Piscis Austrini, Latinized from δ Piscis Austrini, is a yellow-hued star in the southern constellation of Piscis Austrinus. It is visible to the naked eye with an apparent visual magnitude of +4.175. There is a magnitude 9.86 common proper motion companion located at an angular separation of 5.2 arc seconds – the pair most likely form a binary star system. Based upon an annual parallax shift of 18.9796 mas as seen from the Gaia satellite, Delta Piscis Austrini is located 172 ± 2 light-years from the Sun.
Epsilon Piscis Austrini, Latinized from ε Piscis Austrini, is a blue-white hued star in the southern constellation of Piscis Austrinus. It is visible to the naked eye with an apparent visual magnitude of +4.17. Based upon an annual parallax shift of 8.0981 ± 0.3582 mas as seen from the GAIA satellite, the system is located roughly 400 light years from the Sun.
Eta Piscis Austrini is binary star system in the southern constellation of Piscis Austrinus. As of 2000, the two components had an angular separation of 1.818 arc seconds along a position angle of 113.4°. The pair have a combined apparent visual magnitude of +5.43, which is bright enough to be seen with the naked eye. Based upon an annual parallax shift of 3.99 mas as seen from the Earth, the system is located roughly 820 light years from the Sun.
Mu Piscis Austrini, Latinized from μ Piscis Austrini, is a solitary, white-hued star in the southern constellation of Piscis Austrinus. It is visible to the naked eye with an apparent visual magnitude of +4.49. Based upon an annual parallax shift of 26.75 mas as seen from the Gaia space telescope, the star is located around 122±2 light years from the Sun.
HD 114613 is a fifth magnitude yellow subgiant that lies 66.7 light-years away in the constellation of Centaurus. The star may be host to a long-period giant planet.
HD 41742 and HD 41700 is a star system that lies approximately 88 light-years away in the constellation of Puppis. The system consists of two bright stars where the primary is orbited by two fainter stars, making it a quadruple with an unequal hierarchy.
2 Piscis Austrini, also known as HD 200763 or simply 2 PsA, is a solitary orange hued star located in the southern constellation Microscopium. It was once part of Piscis Austrinus, the southern fish. The object has an apparent magnitude of 5.2, making it faintly visible to the naked eye under ideal conditions. Based on parallax measurements from the Gaia satellite, it is estimated to be 354 light years away from the Solar System. However, it is receding with a poorly constrained heliocentric radial velocity of 3.1 km/s. At its current distance, 2 PsA's brightness is diminished by 0.11 magnitudes due to interstellar dust. It has an absolute magnitude of 0.19.
3 Piscis Austrini, also known as HD 201901 or simply 3 PsA, is an astrometric binary located in the southern constellation Microscopium. It was once part of Piscis Austrinus, the southern fish. The system has a combined apparent magnitude of 5.39, making it faintly visible to the naked eye under ideal conditions. Gaia DR3 parallax measurements imply a distance of 404 light years and it is currently approaching the Solar System with a heliocentric radial velocity of −46.2 km/s. At its current distance, 3 PsA's brightness is diminished by 0.12 magnitudes due to extinction from interstellar dust and it has an absolute magnitude of +0.19.
Gliese 686 is a star in the constellation of Hercules, with an apparent magnitude +9.577. Although it is close to the Solar System – at 26.6 light-years – it is not the closest known star in its constellation, since Gliese 661 is 20.9 light years away. The closest system to this star is the bright μ Herculis, at 4.5 light years. They are followed by GJ 1230 and Gliese 673, at 7.2 and 7.6 light years respectively.
11 Trianguli is a solitary star located in the northern constellation Triangulum, with an apparent magnitude of 5.55. The star is situated 281 light years away but is approaching with a heliocentric radial velocity of −41.614 km/s. It is probably on the horizontal branch fusing helium in its core, and is calculated to be about 6.3 Gyr old. It has a stellar classification of K1 III. It has 2.446 times the mass of the Sun and 12.055 times the radius of the Sun. It shines at 54.6 times the luminosity of the Sun from its photosphere at an effective temperature of 4,572 K.
absolute magnitude is 9.8