Astronomy:GJ 1061

From HandWiki
(Redirected from Astronomy:GJ 1061 d)
Short description: Red dwarf star in the constellation Horologium

Coordinates: Sky map 03h 35m 59.69s, −44° 30′ 45.3″

GJ 1061
GJ 1061 is located in the constellation Horologium.
GJ 1061 is located in the constellation Horologium.
GJ 1061
Location of GJ 1061 in the constellation Horologium

Observation data
Equinox J2000.0]] (ICRS)
Constellation Horologium
Right ascension  03h 35m 59.69916s[1]
Declination −44° 30′ 45.7308″[1]
Apparent magnitude (V) 13.03[2]
Characteristics
Spectral type M5.5 V[2]
Apparent magnitude (J) 7.52 ± 0.02[3]
U−B color index 1.52[3]
B−V color index 1.90[3]
Astrometry
Radial velocity (Rv)1.49±0.23[1] km/s
Proper motion (μ) RA: 745.654[1] mas/yr
Dec.: −373.323[1] mas/yr
Parallax (π)272.1615 ± 0.0316[1] mas
Distance11.984 ± 0.001 ly
(3.6743 ± 0.0004 pc)
Absolute magnitude (MV)15.26[4]
Details
Mass0.125±0.003[5] M
Radius0.152±0.007[5] R
Luminosity (bolometric)0.001641±0.000037[5] L
Luminosity (visual, LV)0.00007[nb 1] L
Temperature2,977+72
−69
[5] K
Metallicity [Fe/H]−0.03±0.09[5] dex
Rotational velocity (v sin i)≤ 5[6] km/s
Age>7.0±0.5[7] Gyr
Other designations
GJ 1061, LHS 1565, LFT 295, LTT 1702, LP 995-46, L 372-58[3]
Database references
SIMBADdata

GJ 1061 is a red dwarf star located 12 light-years (3.7 parsecs) from Earth in the southern constellation of Horologium. Even though it is a relatively nearby star, it has an apparent visual magnitude of about 13,[2] so it can only be seen with at least a moderately-sized telescope.

The proper motion of GJ 1061 has been known since 1974, but it was estimated to be further away: approximately 25 light-years (7.7 parsecs) distant based upon an estimated parallax of 0.130. The RECONS accurately determined its distance in 1997. At that time, it was the 20th-nearest star system to the Sun. The discovery team noted that many more stars like this are likely to be discovered nearby.[2]

This star is a tiny, dim, red dwarf, close to the lower mass limit. It has an estimated mass of about 12.5% that of the Sun and is only about 0.2% as luminous.[5] The star displays no significant infrared excess due to circumstellar dust.[8]

Planetary system

On August 13, 2019, a planetary system was announced orbiting the star GJ 1061 by the Red Dots project for detecting terrestrial planets around nearby red dwarf stars.[7] The planet GJ 1061 d orbits in the conservative circumstellar habitable zone of its star and the planet GJ 1061 c orbits in the inner edge of the habitable zone.[7] GJ 1061 is a non-variable star that does not suffer flares, so there is a greater probability that the exoplanets still conserve their atmosphere if they had one.[9]

The GJ 1061 planetary system[7]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b ≥1.37+0.16
−0.15
 M
0.021±0.001 3.204±0.001 <0.31
c ≥1.74±0.23 M 0.035±0.001 6.689±0.005 <0.29
d ≥1.64+0.24
−0.23
 M
0.054±0.001 13.031+0.025
−0.032
<0.53

GJ 1061 c

GJ 1061 c is a potentially habitable exoplanet orbiting within the limits of the optimistically defined habitable zone of its red dwarf parent star.[10][11][7]

GJ 1061 c is at least 74% more massive than the Earth. The planet receives 35% more stellar flux than Earth and has an equilibrium temperature of 275 K (2 °C; 35 °F).[12] The average temperature on the surface would be warmer, 34 °C (307 K; 93 °F), provided the atmosphere is of similar composition to the Earth's.

GJ 1061 c orbits its parent star very closely, every 6.7 days at a distance of just 0.035 au, so it is probably gravitationally locked and in synchronous rotation with its star.

GJ 1061 d

GJ 1061 d is a potentially habitable exoplanet largely orbiting within the limits of the conservatively defined habitable zone of its parent red dwarf star.[10][13][7]

The exoplanet is at least 64% more massive than the Earth. The planet receives about 40% less stellar flux than Earth and has an estimated equilibrium temperature of 218 K (−55 °C; −67 °F).[10][7] The average temperature on the surface would be colder than Earth's and at around 250 K (−23 °C; −10 °F), provided the atmosphere is similar to that of Earth.

GJ 1061 d orbits its star every 13 days, and due to its close-in semi-major axis, it is likely that the exoplanet is tidally locked.[14] However, if the planet's orbit is confirmed to be highly eccentric then this eccentricity could be desynchronising it, enabling the existence of non-synchronised states of equilibrium in its rotation, relative to which side of the planet is facing the star, and thereby it will experience a day/night cycle.[15]

Another solution for this planet gives it a slightly shorter period of 12.4 days and a slightly smaller minimum mass of 1.53 M.[7]

See also

Notes

  1. Taking the absolute visual magnitude of GJ 1061, [math]\displaystyle{ \scriptstyle M_{V_{\ast}} = 15.26 }[/math], and the absolute visual magnitude of the Sun, [math]\displaystyle{ \scriptstyle M_{V_{\odot}} = 4.83 }[/math], the visual luminosity of GJ 1061 can therefore be calculated: [math]\displaystyle{ \scriptstyle \frac{L_{V_{\ast}}}{L_{V_{\odot}}} = 10^{0.4\left(M_{V_{\odot}} - M_{V_{\ast}}\right)} = 6.73\times10^{-5} }[/math]

References

  1. 1.0 1.1 1.2 1.3 1.4 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940  Gaia DR3 record for this source at VizieR.
  2. 2.0 2.1 2.2 2.3 Henry, Todd J. et al. (1997). "The solar neighborhood IV: discovery of the twentieth nearest star". The Astronomical Journal 114: 388–395. doi:10.1086/118482. Bibcode1997AJ....114..388H. 
  3. 3.0 3.1 3.2 3.3 "LHS 1565". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=LHS+1565. 
  4. Scholz, R.-D. et al. (2000). "New high-proper motion survey in the Southern sky". Astronomy and Astrophysics 353: 958–969. Bibcode2000A&A...353..958S. 
  5. 5.0 5.1 5.2 5.3 5.4 5.5 Pineda, J. Sebastian; Youngblood, Allison; France, Kevin (September 2021). "The M-dwarf Ultraviolet Spectroscopic Sample. I. Determining Stellar Parameters for Field Stars". The Astrophysical Journal 918 (1): 23. doi:10.3847/1538-4357/ac0aea. 40. Bibcode2021ApJ...918...40P. 
  6. Barnes, J. R. et al. (April 2014). "Precision radial velocities of 15 M5-M9 dwarfs". Monthly Notices of the Royal Astronomical Society 439 (3): 3094–3113. doi:10.1093/mnras/stu172. Bibcode2014MNRAS.439.3094B. 
  7. 7.0 7.1 7.2 7.3 7.4 7.5 7.6 7.7 Dreizler, S.; Jeffers, S. V.; Rodríguez, E.; Zechmeister, M.; Barnes, J.R.; Haswell, C.A.; Coleman, G. A. L.; Lalitha, S. et al. (2019-08-13). "Red Dots: A temperate 1.5 Earth-mass planet in a compact multi-terrestrial planet system around GJ1061" (in en). Monthly Notices of the Royal Astronomical Society 493 (1): 536. doi:10.1093/mnras/staa248. Bibcode2020MNRAS.493..536D. 
  8. Avenhaus, H. et al. (December 2012). "The nearby population of M-dwarfs with WISE: a search for warm circumstellar dust". Astronomy & Astrophysics 548: 15. doi:10.1051/0004-6361/201219783. A105. Bibcode2012A&A...548A.105A. 
  9. Starr, Michelle (27 August 2019). "Three Rocky Exoplanets Have Been Found Orbiting a Star Just 12 Light-Years Away" (in en-gb). https://www.sciencealert.com/three-rocky-exoplanets-have-been-found-orbiting-a-star-just-12-light-years-away. 
  10. 10.0 10.1 10.2 "The Habitable Exoplanets Catalog - Planetary Habitability Laboratory @ UPR Arecibo". http://phl.upr.edu/projects/habitable-exoplanets-catalog. 
  11. "Exoplanet-catalog". https://exoplanets.nasa.gov/exoplanet-catalog/7592/gj-1061-c/. 
  12. "Trio of Super-Earths Found Orbiting Red Dwarf Gliese 1061 | Astronomy | Sci-News.com" (in en-US). http://www.sci-news.com/astronomy/trio-super-earths-red-dwarf-gliese-1061-07555.html. 
  13. "GJ 1061 d". https://exoplanetarchive.ipac.caltech.edu/cgi-bin/DisplayOverview/nph-DisplayOverview?objname=GJ%201061%20d&type=CONFIRMED_PLANET. 
  14. "Exoplanet-catalog". https://exoplanets.nasa.gov/exoplanet-catalog/7593/gj-1061-d/. 
  15. Auclair-Desrotour, P. et al. (2019). "Final spin states of eccentric ocean planets". Astronomy & Astrophysics (EDP Sciences) 629: A132. doi:10.1051/0004-6361/201935905. ISSN 0004-6361. Bibcode2019A&A...629A.132A. "While the semidiurnal tide drives the body towards the spin-orbit synchronous rotation, eccentricity tides tend to desynchronise it, and thereby enable the existence of non-synchronised states of equilibrium.". 

External links