Lacaille 9352

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 even 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[12] and is the closest star in the constellation Piscis Austrinus. The ChView simulation[13] shows that its closest neighbour is the EZ Aquarii triple star system at about 4.1 ly away.

Properties

This star has the fourth highest known proper motion,[14] (which was first noticed by Benjamin Gould in 1881[15]) 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.[16] 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.[17]

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,[18] with the physical diameter being about 46% of the Sun's radius.[3] It has around half the mass of the Sun[3] and the outer envelope has an effective temperature of about 3,626 K.[3]
Planetary system

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, were this planet 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.[19][20]
The Lacaille 9352 planetary system 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 — —
See also

List of nearest stars
Lacaille 9352 in fiction

References

van Leeuwen, F. (November 2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. S2CID 18759600.
Cousins, A. W. J. (1973). "UBV photometry of some southern stars". Monthly Notes of the Astronomical Society of Southern Africa. 32: 11. Bibcode:1973MNSSA..32...11C.
Demory, B.-O.; et al. (October 2009), "Mass-radius relation of low and very low-mass stars revisited with the VLTI", Astronomy and Astrophysics, 505 (1): 205–215, arXiv:0906.0602, Bibcode:2009A&A...505..205D, doi:10.1051/0004-6361/200911976, S2CID 14786643
Micela, G.; Pye, J.; Sciortino, S. (April 1997). "Coronal properties of nearby old disk and halo dM stars". Astronomy and Astrophysics. 320: 865–877. Bibcode:1997A&A...320..865M.
Torres, G. R.; et al. (December 2006). "Search for associations containing young stars (SACY). I. Sample and searching method". Astronomy and Astrophysics. 460 (3): 695–708. arXiv:astro-ph/0609258. Bibcode:2006A&A...460..695T. doi:10.1051/0004-6361:20065602. S2CID 16080025.
Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
Murdin, Paul, ed. (November 2000). "Lacaille 9352". Encyclopedia of Astronomy and Astrophysics. Bristol: Institute of Physics Publishing. Bibcode:2000eaa..bookE5158.. doi:10.1888/0333750888/5158. ISBN 0333750888. "absolute magnitude is 9.8"
Rabus, Markus; Lachaume, Régis; Jordán, Andrés; Brahm, Rafael; Boyajian, Tabetha; Von Braun, Kaspar; Espinoza, Néstor; Berger, Jean-Philippe; Le Bouquin, Jean-Baptiste; Absil, Olivier (2019). "A discontinuity in the Teff–radius relation of M-dwarfs". Monthly Notices of the Royal Astronomical Society. 484 (2): 2674–2683. arXiv:1901.08077. Bibcode:2019MNRAS.484.2674R. doi:10.1093/mnras/sty3430. S2CID 119189542.
López-Morales, Mercedes (May 2007). "On the Correlation between the Magnetic Activity Levels, Metallicities, and Radii of Low-Mass Stars". The Astrophysical Journal. 660 (1): 732–739. arXiv:astro-ph/0701702. Bibcode:2007ApJ...660..732L. doi:10.1086/513142. S2CID 119530297.
Yee, Samuel W.; Petigura, Erik A.; von Braun, Kaspar (2017). "Precision Stellar Characterization of FGKM Stars using an Empirical Spectral Library". The Astrophysical Journal. 836 (1): 77. arXiv:1701.00922. Bibcode:2017ApJ...836...77Y. doi:10.3847/1538-4357/836/1/77. S2CID 6302522.
"LACAILLE 9352 -- Pre-main sequence Star". SIMBAD. Centre de Données astronomiques de Strasbourg. Retrieved 2010-01-20.
Research Consortium on Nearby Stars. "The One Hundred Nearest Star Systems". Georgia State University. Archived from the original on 2012-05-13. Retrieved 2010-01-20.
"Solstation and ChView". Retrieved 2010-04-20.
"High Proper Motion Stars in the Hipparcos Catalogue". European Space Agency. July 1, 2007. Retrieved 2010-01-20.
Gould, B. A. (1881). "Corrigenda in the Uranometria Argentina. Star with large proper motion". Astronomische Nachrichten. 100 (1): 7–10. Bibcode:1881AN....100....7G. doi:10.1002/asna.18811000104.
"ARICNS star page of Lacaille 9352". Astronomisches Rechen-Institut Heidelberg. Retrieved 2010-04-16.
"Annotations on NAME LACAILLE 9352 object". SIMBAD. Centre de Données astronomiques de Strasbourg. Retrieved 2010-04-16.
Glindemann, Andreas; Paresce, Francesco. "Giant Eyes for the VLT Interferometer". European Southern Observatory. Retrieved 2010-01-20.
Jeffers, S. V.; Dreizler, S.; et al. (June 2020). "A multiplanet system of super-Earths orbiting the brightest red dwarf star GJ 887". Science. 368 (6498): 1477–1481. arXiv:2006.16372. Bibcode:2020Sci...368.1477J. doi:10.1126/science.aaz0795. ISSN 0036-8075. PMID 32587019. S2CID 220075207.

"Why boring could be good for this star's two intriguing planets". Nature. Retrieved 2020-06-30.

External links

SolStation.com: Lacaille 9352

vte

← Celestial objects within 10–15 light-years →
Primary member type
Celestial objects by systems.
Subgiant stars
F-type

Procyon (α CMi) (11.41+0.04
−0.03 ly) white dwarf B

Main-sequence
stars
G-type

τ Cet (11.905±0.007 ly) 4 (8?) planets: (b), (c), (d), e, f, g, h, (i)

K-type

ε Eri (Ran) (10.475±0.003 ly) 1 (2?) planets: b (Ægir), c? 61 Cyg (11.409±0.022 ly) K-type main-sequence star B ε Ind (11.815±0.012 ly) 2 T-type brown dwarfs: Ba, Bb planet Ab

M-type
(red dwarfs)

Ross 248 (10.298±0.023 ly) Lac 9352 (10.685+0.025
−0.024 ly) 2 (3?) planets: b, c, d? Ross 128 (10.94±0.06 ly) planet b EZ Aqr (11.08±0.13 ly) 2 red dwarfs: B, C Σ 2398 (11.40±0.07 ly) red dwarf B 2 planets: Bb, Bc Gmb 34 (11.70±0.03 ly) red dwarf B 2 planets: Ab, Ac DX Cnc (11.83±0.13 ly) Gliese 1061 (12.04±0.06 ly) 3 planets: b, c, d YZ Cet (12.20±0.14 ly) 3 (4?) planets: b, c, d, e? Luyten's Star (12.20±0.04 ly) 4 planets: b, c, d, e SCR 1845-6357 (12.57±0.05 ly) T-type brown dwarf B Teegarden's star (12.58±0.05 ly) 2 planets: b, c Kapteyn's Star (12.78±0.04 ly) 2 planets: b, c Lac 8760 (12.87±0.04 ly) Kruger 60 (13.18±0.08 ly) red dwarf B Ross 614 (13.36±0.04 ly) red dwarf B Wolf 1061 (14.0±0.1 ly) 3 planets: b, c, d Wolf 424 (14.05+0.27
−0.26 ly) red dwarf B GJ 1 (14.15±0.06 ly) TZ Ari (14.584±0.07 ly) LHS 292 (14.89±0.01 ly) GJ 687 (14.77±0.06 ly) planet b GJ 674 (14.81+0.10
−0.09 ly) planet b G 208-44 (14.81±0.07 ly) 2 red dwarfs: B G 208-45

Degenerate
stars
White dwarfs

van Maanen 2 (14.03+0.12
−0.11 ly)

Brown dwarfs
M-type

DEN 1048−3956 (13.15±0.03 ly) 2M1540 (17.344±0.009 ly)

T-type

WISE 1506+7027 (11.1+2.3
−1.3 ly) UGPS J0722-0540 (13.43±0.13 ly)

Y-type

WISE 0350−5658 (12.1+5.2
−1.3 ly)

Italic are systems without known trigonometric parallax.

vte

Constellation of Piscis Austrinus

List of stars in Piscis Austrinus Piscis Austrinus in Chinese astronomy