AB Andromedae

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AB Andromedae
ABAndLightCurve.png
The visual band light curve of AB Andromedae, adapted from Parimucha et al. [1]
Observation data
Epoch J2000       Equinox J2000
Constellation Andromeda
Right ascension 23h 11m 32.08609s [2]
Declination +36° 53 35.10721 [2]
Apparent magnitude  (V)9.49 ( 10.32) 10.46 [3]
Characteristics
Spectral type G5+G5V [3]
Apparent magnitude  (B)10.62 [4]
Apparent magnitude  (V)9.675 [4]
Apparent magnitude  (G)9.6953 [2]
Apparent magnitude  (J)8.172 [5]
Apparent magnitude  (H)7.805 [5]
Apparent magnitude  (K)7.665 [5]
B−V color index 0.9163 [4]
Variable type EW
Astrometry
Radial velocity (Rv)−27.53±0.67 [6]  km/s
Proper motion (μ)RA: 107.923±0.046 [2]   mas/yr
Dec.: −53.357±0.036 [2]   mas/yr
Parallax (π)11.7027 ± 0.0367  mas [2]
Distance 278.7 ± 0.9  ly
(85.5 ± 0.3  pc)
Orbit [7]
Period (P)0.3319 days
Semi-major axis (a)2.308 R [8]
Eccentricity (e)0.002±0.001
Argument of periastron (ω)
(secondary)
40±5°
Argument of periastron (ω)
(primary)
220±5°
Semi-amplitude (K1)
(primary)
233±1 km/s
Semi-amplitude (K2)
(secondary)
133±1 km/s
Details [9]
Primary
Mass 1.04  M
Radius 1.03  R
Surface gravity (log g)4.392 [10]   cgs
Temperature 5,798  K
Age 5.53±2.00 [8]   Gyr
Secondary
Mass 0.60  M
Radius 0.78  R
Surface gravity (log g)4.347 [10]   cgs
Temperature 5,450  K
Age 5.53±2.00 [8]   Gyr
Other designations
2MASS J23113209+3653351, BD+36 5017, HIP  114508, SAO  73069, TYC 2763-904-1
Database references
SIMBAD data

AB Andromedae (AB And) is a binary star in the constellation Andromeda. Paul Guthnick and Richard Prager discovered that the star is an eclipsing binary in 1927. [11] [12] Its maximum apparent visual magnitude is 9.49 but shows a variation in brightness down to a magnitude of 10.46 in a periodic cycle of roughly 8 hours. The observed variability is typical of W Ursae Majoris variable stars, [3] so the two stars in this system form a contact binary.

Contents

System

The observed spectral type of both stars in this system is G5, and one of them is a main sequence star very similar to the sun. [3] They are orbiting so close that their envelopes touch each other. This is a dynamically stable phase that should last until one of the two stars leaves the main sequence.

The system could also host a third body with an orbital period of 19,046 days, with a minimum mass of 0.007 M and an eccentricity of 0.22, but not all data collected in time are consistent with this hypothesis. [7]

Variability

The two stars eclipse each other during their orbit, but they have an elongated shape so they show a constant variation instead of discrete eclipses. Anyway, a periodicity can be seen clearly, but it changes with time; the period shows a long-term trend and a periodic modulation of 7,000 days. The effects responsible for this behaviour could be a third body in the system, magnetic interaction between two stars, [9] mass transfer from one star to the other, mass loss of the system, and recently even an internal mechanism in the touching envelopes have been proposed. [10]

Related Research Articles

<span class="mw-page-title-main">W Ursae Majoris</span> Star in the constellation Ursa Major

W Ursae Majoris is the variable star designation for a binary star system in the northern constellation of Ursa Major. It has an apparent visual magnitude of about 7.9, which is too faint to be seen with the naked eye. However, it can be viewed with a small telescope. Parallax measurements place it at a distance of roughly 169 light years (52 parsecs) from Earth.

Xi Ursae Majoris is a quintuple star system 28.5 light-years away in the constellation of Ursa Major. It has the traditional name Alula Australis; Xi Ursae Majoris is the Bayer designation, which is Latinised from ξ Ursae Majoris and abbreviated Xi UMa or ξ UMa. It was the first visual double star for which an orbit was calculated, when it was computed by Félix Savary in 1828. It is also a variable star with a small amplitude. Xi Ursae Majoris is found in the left hind paw of the Great Bear.

<span class="mw-page-title-main">S Antliae</span> Star in the constellation Antlia

S Antliae is a W Ursae Majoris-type eclipsing binary star in Antlia.

<span class="mw-page-title-main">65 Ursae Majoris</span> Star system in the constellation Ursa Major

65 Ursae Majoris, abbreviated as 65 UMa, is a star system in the constellation of Ursa Major. With a combined apparent magnitude of about 6.5, it is at the limit of human eyesight and is just barely visible to the naked eye in ideal conditions. It is about 760 light years away from Earth.

<span class="mw-page-title-main">SU Ursae Majoris</span> Variable star in the constellation Ursa Major

SU Ursae Majoris, or SU UMa, is a close binary star in the northern circumpolar constellation of Ursa Major. It is a periodic cataclysmic variable that varies in magnitude from a peak of 10.8 down to a base of 14.96. The distance to this system, as determined from its annual parallax shift of 4.53 mas, is 719 light-years. It is moving further from the Earth with a heliocentric radial velocity of +27 km/s.

<span class="mw-page-title-main">QX Andromedae</span> Eclipsing binary star system in the constellation Andromeda

QX Andromedae is an eclipsing binary in the constellation Andromeda. It varies from a maximum apparent visual magnitude of 11.28 to a minimum of 11.50. Since it is impossible to specify the onset time of the eclipses, it is classified as a W Ursae Majoris variable star. It is also observed as an X-ray source and is a member of the open cluster NGC 752.

<span class="mw-page-title-main">AE Phoenicis</span> Star in the constellation Phoenix

AE Phoenicis is a variable star in the constellation of Phoenix. An eclipsing binary, its apparent magnitude has a maximum of 7.56, dimming to 8.25 during primary eclipse and 8.19 during secondary eclipse. From parallax measurements by the Gaia spacecraft, the system is located at a distance of 168 light-years from Earth.

<span class="mw-page-title-main">V752 Centauri</span> Star in the constellation Centaurus

V752 Centauri is multiple star system and variable star in the constellation of Centaurus. An eclipsing binary, its apparent magnitude has a maximum of 9.10, dimming to 9.66 during primary eclipse and 9.61 during secondary eclipse. Its variability was discovered by Howard Bond in 1970. From parallax measurements by the Gaia spacecraft, the system is located at a distance of 410 light-years from Earth.

<span class="mw-page-title-main">TU Ursae Majoris</span>

TU Ursae Majoris is a variable star in the northern circumpolar constellation of Ursa Major. It is classified as a Bailey-type 'ab' RR Lyrae variable with a period of 0.557648 days that ranges in brightness from apparent visual magnitude of 9.26 down to 10.24. The distance to this star is approximately 2,090 light years based on parallax measurements. It is located near the north galactic pole at a distance that indicates this is a member of the galactic halo.

<span class="mw-page-title-main">TX Ursae Majoris</span> Eclipsing binary star system in the constellation of Ursa Major

TX Ursae Majoris is an eclipsing binary star system in the northern circumpolar constellation of Ursa Major. With a combined apparent visual magnitude of 6.97, the system is too faint to be readily viewed with the naked eye. The pair orbit each other with a period of 3.063 days in a circular orbit, with their orbital plane aligned close to the line of sight from the Earth. During the primary eclipse, the net brightness decreases by 1.74 magnitudes, while the secondary eclipse results in a drop of just 0.07 magnitude. TX UMa is located at a distance of approximately 780 light years from the Sun based on parallax measurements, but is drifting closer with a mean radial velocity of −13 km/s.

<span class="mw-page-title-main">UX Ursae Majoris</span> Variable star in the constellation Ursa Major

UX Ursae Majoris is an Algol type binary star system in the northern circumpolar constellation of Ursa Major. It is classified as a nova-like variable star similar to DQ Herculis, although no eruptions have been reported. Since its discovery in 1933, this system has been the subject of numerous studies attempting to determine its properties. The combined apparent visual magnitude of UX UMa ranges from 12.57 down to 14.15. The system is located at a distance of approximately 952 light years from the Sun based on parallax, and is drifting further away with a radial velocity of 112 km/s.

<span class="mw-page-title-main">XY Ursae Majoris</span> Eclipsing binary star system in the constellation of Ursa Major

XY Ursae Majoris is a short period binary star system in the northern circumpolar constellation of Ursa Major. It is an eclipsing binary with a baseline apparent visual magnitude of 9.50. The system is located at a distance of 221.5 light years from the Sun based on parallax measurements, but is drifting closer with a radial velocity of −10 km/s. It has a relatively high proper motion, traversing the celestial sphere at the angular rate of 0.191″·yr−1.

<span class="mw-page-title-main">EQ Tauri</span>

EQ Tauri is a triple star system in the equatorial constellation of Taurus that includes a contact eclipsing binary. The system is too faint to be viewed with the naked eye, having a baseline apparent visual magnitude of 10.5. During the primary eclipse, the brightness of the system drops to magnitude 11.03, then to 10.97 during the secondary minimum. The secondary eclipse is total. Based on parallax measurements, it is located at a distance of approximately 730 light years from the Sun.

<span class="mw-page-title-main">AG Virginis</span> Eclipsing binary star in the constellation Virgo

AG Virginis is an eclipsing binary star system in the equatorial constellation of Virgo. With a maximum apparent visual magnitude of 8.51 it is too faint to be visible to the naked eye. The system is located at a distance of approximately 820 light years from the Sun based on parallax measurements.

<span class="mw-page-title-main">AH Virginis</span> Star in the constellation Virgo

AH Virginis is a contact binary star system in the equatorial constellation of Virgo, abbreviated AH Vir. It is a variable star with a brightness that peaks at an apparent visual magnitude of 9.18, making it too faint to be viewed with the naked eye. The distance to this system is approximately 338 light years based on parallax measurements, and it is drifting further away with a mean radial velocity of 7 km/s. O. J. Eggen in 1969 included this system as a probable member of the Wolf 630 group of co-moving stars.

<span class="mw-page-title-main">SW Ursae Majoris</span> Variable star in the constellation Ursa Major

SW Ursae Majoris is a cataclysmic binary star system in the northern circumpolar constellation of Ursa Major, abbreviated SW UMa. During quiescence it has an apparent visual magnitude of 16.5–17, which is too faint to be visible to the naked eye. Based on parallax measurements, it is located at a distance of approximately 526 light years from the Sun.

<span class="mw-page-title-main">VV Ursae Majoris</span> Variable star system in the constellation Ursa Major

VV Ursae Majoris is a binary star system in the northern circumpolar constellation of Ursa Major, abbreviated VV UMa. It is a variable star system with a brightness that cycles around an apparent visual magnitude of 10.19, making it too faint to be visible to the naked eye. The system is located at a distance of approximately 1,500 light years based on parallax measurements.

<span class="mw-page-title-main">AW Ursae Majoris</span> Variable star in the constellation Ursa Major

AW Ursae Majoris is a binary star system in the northern circumpolar constellation of Ursa Major, abbreviated AW UMa. It is an A-type W Ursae Majoris variable with an apparent visual magnitude of 6.83, which is near the lower limit of visibility to the naked eye. This is an eclipsing binary with the brightness dropping to magnitude 7.13 during the primary eclipse and to 7.08 with the secondary eclipse. Parallax measurements give a distance estimate of 221 light years from the Sun. It is drifting closer to the Sun with a radial velocity of approximately −17 km/s. The system has a high proper motion, traversing the celestial sphere at the rate of 0.216 arc second per annum.

<span class="mw-page-title-main">DW Ursae Majoris</span> Variable star in the constellation Ursa Major

DW Ursae Majoris is an eclipsing binary star system in the northern circumpolar constellation of Ursa Major, abbreviated DW UMa. It is a cataclysmic variable of the SX Sextanis type, consisting of a compact white dwarf that is accreting matter from an orbiting companion star. The brightness of this source ranges from an apparent visual magnitude of 13.6 down to magnitude 18, which is too faint to be viewed with the naked eye. The distance to this system is approximately 1,920 light years based on parallax measurements.

U Pegasi is a binary star system in the constellation of Pegasus, abbreviated U Peg. The pair form an eclipsing binary with a combined peak apparent visual magnitude of 9.23, which is far too faint to be visible to the naked eye. During the primary eclipse the magnitude decreases to 10.07, while the secondary eclipse only drops to magnitude 9.73. This system is located at a distance of approximately 596 light years from the Sun based on parallax measurements, but is drifting closer with a radial velocity of around −28.5 km/s.

References

  1. Parimucha, Stefan; Pribulla, Theodor; Vanko, Martin (January 2000). "New Photoelectric Light Curves of AB Andromedae". Information Bulletin on Variable Stars. 4834: 1. Bibcode:2000IBVS.4834....1P . Retrieved 6 October 2021.
  2. 1 2 3 4 5 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.
  3. 1 2 3 4 AB And, database entry, Combined General Catalog of Variable Stars (GCVS4.2, 2004 Ed.), N. N. Samus, O. V. Durlevich, et al., CDS ID II/250 Accessed on line 2018-10-22.
  4. 1 2 3 Høg, E.; Fabricius, C.; Makarov, V. V.; Urban, S.; Corbin, T.; Wycoff, G.; Bastian, U.; Schwekendiek, P.; Wicenec, A. (2000), "The Tycho-2 catalogue of the 2.5 million brightest stars", Astronomy & Astrophysics, 355: L27–L30, Bibcode:2000A&A...355L..27H.
  5. 1 2 3 Cutri, Roc M.; Skrutskie, Michael F.; Van Dyk, Schuyler D.; Beichman, Charles A.; Carpenter, John M.; Chester, Thomas; Cambresy, Laurent; Evans, Tracey E.; Fowler, John W.; Gizis, John E.; Howard, Elizabeth V.; Huchra, John P.; Jarrett, Thomas H.; Kopan, Eugene L.; Kirkpatrick, J. Davy; Light, Robert M.; Marsh, Kenneth A.; McCallon, Howard L.; Schneider, Stephen E.; Stiening, Rae; Sykes, Matthew J.; Weinberg, Martin D.; Wheaton, William A.; Wheelock, Sherry L.; Zacarias, N. (2003). "VizieR Online Data Catalog: 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)". CDS/ADC Collection of Electronic Catalogues. 2246: II/246. Bibcode:2003yCat.2246....0C.
  6. Bilir, S.; Karataș, Y.; Demircan, O.; Eker, Z. (February 2005), "Kinematics of W Ursae Majoris type binaries and evidence of the two types of formation", Monthly Notices of the Royal Astronomical Society, 357 (2): 497–517, arXiv: astro-ph/0411291 , Bibcode:2005MNRAS.357..497B, doi: 10.1111/j.1365-2966.2005.08609.x .
  7. 1 2 Karami, K.; Ghaderi, K.; Mohebi, R.; Sadeghi, R.; Soltanzadeh, M. M. (June 2009), "Velocity-Curve Analysis of the Spectroscopic Binary Stars V373 Cas, V2388 Oph, V401 Cyg, GM Dra, V523 Cas, AB And and HD 141929 by Artificial Neural Networks", Publications of the Astronomical Society of Australia, 26 (2): 121–127, arXiv: 0907.4411 , Bibcode:2009PASA...26..121K, doi:10.1071/AS09010, S2CID   119247525.
  8. 1 2 3 Yıldız, M. (2014), "Origin of W UMa-type contact binaries - age and orbital evolution", Monthly Notices of the Royal Astronomical Society, 437 (1): 185–194, arXiv: 1310.5526 , Bibcode:2014MNRAS.437..185Y, doi: 10.1093/mnras/stt1874 , S2CID   119121897.
  9. 1 2 Borkovits, T.; Elkhateeb, M. M.; Csizmadia, Cz.; Nuspl, J.; Bíró, I. B.; Hegedüs, T.; Csorvási, R. (2005), "Indirect evidence for short period magnetic cycles in W UMa stars. Period analysis of five overcontact systems.", Astronomy & Astrophysics, 441 (3): 1087–1097, arXiv: astro-ph/0507228 , Bibcode:2005A&A...441.1087B, doi: 10.1051/0004-6361:20052805 .
  10. 1 2 3 Liu, L.; Qian, S. B.; Xiong, X. (2018), "A new mechanism of long-term period variations for W UMa-type contact binaries", Monthly Notices of the Royal Astronomical Society, 474 (4): 5199–5205, arXiv: 1712.04358 , Bibcode:2018MNRAS.474.5199L, doi: 10.1093/mnras/stx3138 , S2CID   54501434.
  11. Oosterhoff, P. Th. (February 1929). "Epochs of minimum of AB Andromedae". Bulletin of the Astronomical Institutes of the Netherlands. 5: 37–40. Bibcode:1929BAN.....5...37O . Retrieved 24 February 2023.
  12. Guthnick, P.; Prager, R. (November 1927). "Benennung von veränderlichen Sternen" . Astronomische Nachrichten. 231 (10): 161–172. Bibcode:1927AN....231..161G. doi:10.1002/asna.19272311002 . Retrieved 24 February 2023.