EBLM J0555-57

Last updated
EBLM J0555-57AB
EBLM J0555-57.jpg
Resolved image of EBLM J0555-57A (left) and EBLM J0555-57B (right) taken with the Leonhard Euler Telescope at the ESO's La Silla Observatory [1]
Credit: ESO
Observation data
Epoch J2000       Equinox J2000
Constellation Pictor
EBLM J0555-57A
Right ascension 05h 55m 32.6885s [2]
Declination −57° 17′ 26.067″ [2]
Apparent magnitude  (V)9.98 [1]
EBLM J0555-57B
Right ascension 05h 55m 32.3944s [3]
Declination −57° 17′ 26.748″ [3]
Apparent magnitude  (V)10.76 [1]
Characteristics
EBLM J0555-57A
Spectral type F8 [4]
Variable type Eclipsing [1]
EBLM J0555-57B
Spectral type G0V[ citation needed ]
Astrometry
EBLM J0555-57A
Radial velocity (Rv)18.66±0.74 [5]  km/s
Proper motion (μ)RA: 2.972 [2]   mas/yr
Dec.: −39.532 [2]   mas/yr
Parallax (π)4.8611 ± 0.0137  mas [2]
Distance 671 ± 2  ly
(205.7 ± 0.6  pc)
EBLM J0555-57B
Proper motion (μ)RA: 2.838 [3]   mas/yr
Dec.: −38.344 [3]   mas/yr
Parallax (π)4.8747 ± 0.0175  mas [3]
Distance 669 ± 2  ly
(205.1 ± 0.7  pc)
Position (relative to A)
ComponentB
Epoch of observation 1998
Angular distance 2.50″ [4]
Position angle 254° [4]
Projected separation 479 AU [1]
Orbit [1]
PrimaryAa
CompanionAb
Period (P)7.757676+0.000029
−0.000025  d
Semi-major axis (a)0.0817±0.0019  au
Eccentricity (e)0.0894+0.0035
−0.0036
Inclination (i)89.84+0.2
−1.8°
Argument of periastron (ω)
(secondary)		−53.7+1.5
−1.8°
Details [1]
EBLM J0555-57Aa
Mass 1.13±0.08 [1]   M☉
Radius 0.99+0.15
−0.03 [1]   R☉
Luminosity 3.245 [6]   L☉
Surface gravity (log g)4.18±0.21 [1]   cgs
Temperature 6,461±124 [1]   K
Metallicity [Fe/H]−0.24±0.16 [1]   dex
Rotational velocity (v sin i)7.60±0.28 [1]  km/s
Age 1.9±1.2 [7]   Gyr
EBLM J0555-57Ab
Mass 85.2+4.0
−3.9 [1]   MJup
Radius 0.84+0.14
−0.04 [1]   RJup
Surface gravity (log g)5.50+0.03
−0.13 [1]   cgs
EBLM J0555-57B
Mass 1.01 [8]   M☉
Radius 0.94±0.08 [1]   R☉
Luminosity 1.501 [9]   L☉
Surface gravity (log g)4.37 [8]   cgs
Temperature 5,717±124 [1]   K
Metallicity [Fe/H]−0.38 [8]   dex
Other designations
CD−57 1311, CPD−57 913, WDS J05555-5717, TYC  8528-926, 2MASS J05553262-5717261
Database references
SIMBAD data

EBLM J0555-57 is a triple star system approximately 670 light-years from Earth. EBLM J0555-57Ab, the smallest star in the system, orbits its primary star with a period of 7.8 days, and currently is the smallest known star with a mass sufficient to enable the fusion of hydrogen in its core.

Contents

System

A z' band light curve for EBLM J0555-57, adapted from von Boetticher et al. (2017) EBLMJ0555-57LightCurve.png
A z' band light curve for EBLM J0555-57, adapted from von Boetticher et al. (2017)

EBLM J0555-57, also known as CD−57 1311, is a triple star system [1] [10] in the constellation Pictor, which contains a visual binary system consisting of two sun-like stars separated by 2.5": EBLM J0555-57Aa, a magnitude 9.98 spectral type F8 star, and EBLM J0555-57B, a magnitude 10.76 star. No orbital motion has been detected but they have almost identical radial velocities and are assumed to be gravitationally bound. [1]

Component A of the system is itself an eclipsing binary (EBLM J0555-57Ab orbiting EBLM J0555-57Aa). Eclipses, also known as transits in the context of planetary searches, have been detected in the near infrared, with brightness drops of 0.05% during the eclipse. The shape and duration of the transits allow the radii of the two stars to be determined. A full solution of the orbit gives a period of 7 days and 18 hours, with a low eccentricity of 0.09, an almost edge-on inclination of 89.84°, and a semi-major axis of 0.08 AU. [1]

EBLM J0555-57Ab

EBLM J0555-57Ab has a mass of about 85.2±4 Jupiter masses, or 0.081 solar masses. Its radius is 0.08 solar radii (about 59,000 km), comparable to Saturn, which has an equatorial radius of 60,268 km. The star is about 250 times more massive than Saturn. [1] Current stellar models put its mass at the lower limit for hydrogen-burning stars. EBLM J0555-57Ab was discovered by a group of scientists at the University of Cambridge associated with the EBLM project (Eclipsing Binary, Low Mass), [1] using data collected by the WASP project. WASP (Wide Angle Search for Planets) is searching for exoplanets using the transit method. [11] Additional properties of the star were determined using Doppler spectroscopy, to measure the periodic radial velocity variation of the primary star due to the gravitational influence of its companion. [1]

EBLM J0555-57Ab is the smallest hydrogen burning star currently known.

See also

Related Research Articles

<span class="mw-page-title-main">Winnecke 4</span> Optical double star in the constellation Ursa Major

Winnecke 4 is an optical double star consisting of two unrelated stars in a northerly zone of the sky, Ursa Major.

Gliese 412 is a pair of stars that share a common proper motion through space and are thought to form a binary star system. The pair have an angular separation of 31.4″ at a position angle of 126.1°. They are located 15.8 light-years distant from the Sun in the constellation Ursa Major. Both components are relatively dim red dwarf stars.

<span class="mw-page-title-main">13 Vulpeculae</span> Star in the constellation Vulpecula

13 Vulpeculae is a blue giant with a stellar classification of class B9.5III in the northern constellation Vulpecula. It is visible to the naked eye as a faint, blue-white hued star with an apparent visual magnitude of 4.57 and it is approximately 339 light years away from the Sun based on parallax. The star is radiating 180 times the luminosity of the Sun from its photosphere at an effective temperature of 8,801 K.

HD 6114 is a visual binary star system in the northern constellation of Andromeda. With a combined apparent magnitude of 6.46, the star can only be seen with the naked eye by keen-eyed observers even on the best of nights. Based upon an annual parallax shift of 10.4 mas as seen from Earth's orbit, the system is located approximately 108 parsecs (350 ly) distant.

4 Camelopardalis is a probable multiple star in the northern constellation of Camelopardalis, located 177 light years away from the Sun, based upon parallax. With a combined apparent visual magnitude of 5.29, it is visible to the naked eye as a faint, white-hued star. The pair have a relatively high proper motion, traversing the celestial sphere at an angular rate of 0.158″ per year. The system's proper motion makes it a candidate for membership in the IC 2391 supercluster. They are moving away from the Earth with a heliocentric radial velocity of 22.5 km/s.

<span class="mw-page-title-main">1 Persei</span> Star in the constellation Perseus

1 Persei is an eclipsing binary star in the constellation Perseus. Its uneclipsed apparent magnitude is 5.49. The binary star consists of two B2 type main-sequence stars in a 25.9 day eccentric orbit. The stars are surrounded by a faint cloud of gas visible in mid-infrared, although whether they are the origin of the gas or simply passing through it is unclear.

ADS 9731 is a star system that consists of six stars, located in the constellation of Corona Borealis. Four of the stars are visually separate in the sky, forming a visual star system, which was resolved using adaptive optics in 1995. Two of these stars were themselves found to be spectroscopic binaries in 1998, resulting in a total of six known stars in the system. It is one of very few multiple star systems known to have at least six members.

33 Pegasi is the Flamsteed designation for a visual binary star in the northern constellation of Pegasus. It has an apparent visual magnitude of 6.2, placing it near the limit of naked eye visibility. Measurements show an annual parallax shift of 0.0298125″, which is equivalent to a distance of 109 ly (33 pc) from the Sun. It is drifting further away with a radial velocity of 24 km/s.

<span class="mw-page-title-main">DS Tucanae</span> Binary star system in the constellation of Tucana

DS Tucanae is a binary star system 144 light years away in the constellation of Tucana. It has an apparent visual magnitude of 8.5, and is a RS Canum Venaticorum variable. The system is notable for being young as a member of the 45 Myr old Tucana-Horologium moving group and for the primary star hosting the confirmed exoplanet DS Tucanae Ab, discovered by THYME, using TESS.

<span class="mw-page-title-main">1 Delphini</span> Star in the constellation Delphinus

1 Delphini is the Flamsteed designation for a close binary star in the equatorial constellation Delphinus. With a combined apparent magnitude of 6.08, it is barely visible to the naked eye, even under ideal conditions. Parallax measurements put the components at a distance 703 and 780 light years respectively. However, its approaching the Solar System with a radial velocity of 15 km/s.

HD 44120 is a wide binary star system in the southern constellation of Pictor. Although visible to the naked eye, it is a challenge to view having an apparent visual magnitude of 6.44. The system is located at a distance of 118 light years from the Sun based on parallax, but it is drifting closer with a radial velocity of −2 km/s. It has an absolute magnitude of 3.57.

HD 155448 is a quintuple star system consisting of 5 young B-type stars. With an apparent magnitude of 8.72, it is too dim to be visible with the naked eye.

<span class="mw-page-title-main">GI Tauri and GK Tauri</span> Binary star system in the constellation of Taurus

GK Tauri is a young T Tauri-type pre-main sequence star in the constellation of Taurus about 421 light years away, belonging to the Taurus Molecular Cloud.

HR 3831, also known as HD 83368, is a binary star system in the southern constellation of Vela at a distance of 233 light years. This object is barely visible to the naked eye as a dim, blue star with an apparent visual magnitude of 6.232. It is approaching the Earth with a heliocentric radial velocity of 4.0±0.3 km/s.

<span class="mw-page-title-main">HD 139319</span> Triple star system in constellation Draco

HD 139319 is a ternary system composed of the binary Algol variable star known as TW Draconis, and a main-sequence companion star at a separation of 3 arcseconds. The system lies in the constellation of Draco about 540 light years away.

<span class="mw-page-title-main">HD 165590</span> Triple star system in constellation Hercules

HD 165590 is a quintuple system dominated by the binary Algol variable star known as V772 Herculis. The system lies in the constellation of Hercules about 123 light years from the Sun, and is suspected to be a part of the Pleiades moving group.

HD 72945 and HD 72946 form a co-moving star system in the northern constellation of Cancer. HD 72945 is a binary star that is dimly visible to the naked eye as a point of light with an apparent visual magnitude of 5.91. At an angular separation of 10.10″ is the fainter companion star HD 72946 at magnitude 7.25. It is being orbited by a brown dwarf. The system as a whole is located at a distance of approximately 84 light years from the Sun based on parallax measurements.

HD 193373 is a solitary red hued star located in the equatorial constellation Delphinus. It has an apparent magnitude of 6.21, placing it near the limit for naked eye visibility. Parallax measurements place it 846 light years distant and it is currently receding with a heliocentric radial velocity of 22.7 km/s.

<span class="mw-page-title-main">RS Sagittarii</span> Eclipsing binary star system in the constellation Sagittarius

RS Sagittarii is an eclipsing binary star system in the southern constellation of Sagittarius, abbreviated RS Sgr. It is a double-lined spectroscopic binary with an orbital period of 2.416 days, indicating that the components are too close to each other to be individually resolved. The system has a combined apparent visual magnitude of 6.01, which is bright enough to be faintly visible to the naked eye. During the primary eclipse the brightness drops to magnitude 6.97, while the secondary eclipse is of magnitude 6.28. The distance to this system is approximately 1,420 light years based on parallax measurements.

References

  1. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 von Boetticher, Alexander; Triaud, Amaury H. M. J.; Queloz, Didier; Gill, Sam; Lendl, Monika; Delrez, Laetitia; Anderson, David R.; Collier Cameron, Andrew; Faedi, Francesca; et al. (2017). "The EBLM project III. A Saturn-size low-mass star at the hydrogen-burning limit". Astronomy and Astrophysics. 1706: L6. arXiv: 1706.08781 . Bibcode:2017A&A...604L...6V. doi:10.1051/0004-6361/201731107. S2CID   54610182.
  2. 1 2 3 4 5 Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics . 649: A1. arXiv: 2012.01533 . Bibcode:2021A&A...649A...1G. doi: 10.1051/0004-6361/202039657 . S2CID   227254300. (Erratum:  doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR.
  3. 1 2 3 4 5 Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics . 649: A1. arXiv: 2012.01533 . Bibcode:2021A&A...649A...1G. doi: 10.1051/0004-6361/202039657 . S2CID   227254300. (Erratum:  doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR.
  4. 1 2 3 Mason, Brian D.; Wycoff, Gary L.; Hartkopf, William I.; Douglass, Geoffrey G.; Worley, Charles E. (2001). "The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog". The Astronomical Journal. 122 (6): 3466. Bibcode:2001AJ....122.3466M. doi: 10.1086/323920 .
  5. ↑ Kunder, Andrea; Kordopatis, Georges; Steinmetz, Matthias; Zwitter, Tomaž; McMillan, Paul J.; Casagrande, Luca; Enke, Harry; Wojno, Jennifer; Valentini, Marica; Chiappini, Cristina; Matijevič, Gal; Siviero, Alessandro; De Laverny, Patrick; Recio-Blanco, Alejandra; Bijaoui, Albert; Wyse, Rosemary F. G.; Binney, James; Grebel, E. K.; Helmi, Amina; Jofre, Paula; Antoja, Teresa; Gilmore, Gerard; Siebert, Arnaud; Famaey, Benoit; Bienaymé, Olivier; Gibson, Brad K.; Freeman, Kenneth C.; Navarro, Julio F.; Munari, Ulisse; et al. (2017). "The Radial Velocity Experiment (RAVE): Fifth Data Release". The Astronomical Journal. 153 (2): 75. arXiv: 1609.03210 . Bibcode:2017AJ....153...75K. doi: 10.3847/1538-3881/153/2/75 . S2CID   118835808.
  6. ↑ 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.
  7. ↑ von Boetticher, Alexander; et al. (2019). "The EBLM Project". Astronomy & Astrophysics. 625: A150. arXiv: 1903.10808 . Bibcode:2019A&A...625A.150V. doi:10.1051/0004-6361/201834539. S2CID   85517239.
  8. 1 2 3 Anders, F.; Khalatyan, A.; Queiroz, A. B. A.; Chiappini, C.; Ardevol, J.; Casamiquela, L.; Figueras, F.; Jimenez-Arranz, O.; Jordi, C.; Monguio, M.; Romero-Gomez, M.; Altamirano, D.; Antoja, T.; Assaad, R.; Cantat-Gaudin, T.; Castro-Ginard, A.; Enke, H.; Girardi, L.; Guiglion, G.; Khan, S.; Luri, X.; Miglio, A.; Minchev, I.; Ramos, P.; Santiago, B. X.; Steinmetz, M. (2022). "VizieR Online Data Catalog: StarHorse2, Gaia EDR3 photo-astrometric distances (Anders+, 2022)". Vizier Online Data Catalog. Bibcode:2022yCat.1354....0A.
  9. ↑ 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.
  10. ↑ Wenz, John (11 July 2017). "This Is the Smallest Star Ever Discovered". Popular Mechanics . Retrieved 17 July 2017.
  11. ↑ "Smallest-ever star discovered by astronomers". Phys.org. 12 July 2017. Retrieved 12 July 2017.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.