Jump to content

AB Doradus: Difference between revisions

From Wikipedia, the free encyclopedia
Browse history interactively
← Previous editNext edit →
Content deleted Content added
VisualWikitext
Fixed URLs
Added refs
Line 1: Line 1:
{{about|the pre-main-sequence quadruple star system in the constellation Doradus|the group of several dozen stars that moves with it|AB Doradus moving group}}
{{about|the star system in the constellation Doradus|the group of stars that moves with it|AB Doradus moving group}}
{{Starbox begin
{{Starbox begin
| name=AB Doradus A/B/C }}
| name=AB Doradus }}
{{Starbox image
{{Starbox image
| image = [[File:ESO - Near-Infrared Image of AB Doradus A and its Companion.jpg|220px]]
| image = [[File:ESO - Near-Infrared Image of AB Doradus A and its Companion.jpg|220px]]
Line 8: Line 8:
{{Starbox observe
{{Starbox observe
| epoch=J2000
| epoch=J2000
| ra={{RA|05|28|44.8489}}<ref name=Gaia>{{cite journal|bibcode=2016A&A...595A...2G|doi=10.1051/0004-6361/201629512|arxiv=1609.04172|title=Gaia Data Release 1|journal=Astronomy & Astrophysics|volume=595|pages=A2|year=2016|author=Gaia Collaboration}}</ref>
| ra={{RA|05|28|44.828}}
| dec={{DEC|−65|26|54.85}}
| dec={{DEC|−65|26|54.946}}<ref name=Gaia/>
| appmag_v=6.98−7.06<ref name=Innis2008/>/13.0
| appmag_v=6.98−7.06<ref name=Innis2008/> / 13.0<ref>{{cite simbad|title=NAME AB Dor B|accessdate=19 July 2017}}</ref>
| constell=[[Dorado]] }}
| constell=[[Dorado]]
}}
{{Starbox character
{{Starbox character
| component1=AB Dor AC
| class=K1Vp + dM3-4e + M8
| class=K0V<ref name=Torres2006/> + M8
| b-v={{val|+0.86|0.02}}<ref name=Innis2008/>
| b-v={{val|+0.86|0.02}}<ref name=Innis2008/>
| u-b=+0.37
| u-b=+0.37
| variable=[[Flare star]] }}
| variable=[[Flare star]]
| component2=AB Dor B
| class2=M5 + M5-6<ref name=Azulay2015/>
}}
{{Starbox astrometry
{{Starbox astrometry
| radial_v=32.40 ± 2.2<ref name=Gontcharov>{{cite journal|title=Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system|author=Gontcharov, G. A.|date=2006|journal=Astronomy Letters|volume=32|issue=11|pages=759–771|bibcode=2006AstL...32..759G|doi=10.1134/S1063773706110065|arxiv=1606.08053}}</ref>
| radial_v=+28.0
| prop_mo_ra=33.16<ref name=HIP>{{cite journal|title=Validation of the new Hipparcos reduction|author=van Leeuwen, F.|display-authors=etal|journal=Astronomy and Astrophysics|volume=474|issue=2|pages=653–664|date=2007|arxiv=0708.1752|bibcode=2007A&A...474..653V|doi=10.1051/0004-6361:20078357}}</ref>
| prop_mo_ra=32.14
| prop_mo_dec=150.97
| prop_mo_dec=150.83<ref name=HIP/>
| parallax=66.92
| parallax=65.93
| p_error=0.54
| p_error=0.57
| absmag_v=5.86<ref name=Holmberg2009/>
| parallax_footnote=<ref name=HIP/>
| absmag_v=
}}
⚫
{{Starbox orbit
| reference=<ref name=Azulay2015/>
| primary=AB Dor Ba
⚫
| name=AB Dor Bb
| period=0.986 ± 0.008
| axis=0.052 ± 0.002
⚫
| eccentricity=0.6 ± 0.1
⚫
| inclination=121 ± 5
⚫
| node=270 ± 15
| periarg=54 ± 20
⚫
| periastron=2003.68 ± 0.05
}}
}}
⚫
{{Starbox visbin |
⚫
name=AB Doradus B |
period= |
axis=135 [[Astronomical unit|AU]] |
⚫
eccentricity= |
⚫
inclination= |
⚫
node= |
⚫
periastron= }}
{{Starbox visbin |
{{Starbox visbin |
name=AB Doradus C |
name=AB Doradus C |
Line 42: Line 52:
periastron= }}
periastron= }}
{{Starbox detail
{{Starbox detail
| component AB Dor A
| component1=AB Dor A
| mass=0.86<ref name=Drake2015/>
| mass=0.86<ref name=Drake2015/>
| radius={{Val|0.96|0.06}}<ref name=Drake2015/>
| radius={{Val|0.96|0.06}}<ref name=Drake2015/>
Line 50: Line 60:
| rotation=0.5148&nbsp;days<ref name=aar17_3_251/>
| rotation=0.5148&nbsp;days<ref name=aar17_3_251/>
| age_myr=50<ref name=aj628_1_L69/>
| age_myr=50<ref name=aj628_1_L69/>
}}
{{Starbox detail | no_heading=y
| component1=AB Dor Ba
| mass=0.28 ± 0.05<ref name=Azulay2015/>
| component2=AB Dor Bb
| mass2=0.25 ± 0.05<ref name=Azulay2015/>
}}
}}
{{Starbox catalog
{{Starbox catalog
| names=AB Dor, [[Cordoba Durchmusterung|CD]] -65°332, [[Henry Draper catalogue|HD]] 36705, [[Hipparcos catalogue|HIP]] 25647. }}
| names={{odlist|V=AB Dor|CD=-65° 332|HD=36705|HIP=25647}}
}}
{{Starbox reference |
{{Starbox reference
Simbad=AB+Doradus }}
| Simbad=AB+Dor
| ARICNS=05660
}}
{{Starbox end}}
{{Starbox end}}
'''AB Doradus''' is a pre-main-sequence quadruple<ref name=Azulay2015/> [[star system]] in the [[constellation]] [[Dorado]]. The primary is a [[flare star]] that shows periodic increases in activity.
'''AB Doradus''' is a pre-main-sequence quadruple<ref name=Azulay2015/> [[star system]] in the [[constellation]] [[Dorado]]. The primary is a [[flare star]] that shows periodic increases in activity.
Line 67: Line 86:
{{reflist|refs=
{{reflist|refs=
<ref name=aar17_3_251>{{citation | last1=Strassmeier | first1=Klaus G. | title=Starspots | journal=The Astronomy and Astrophysics Review | volume=17 | issue=3 | pages=251–308 |date=September 2009 | doi=10.1007/s00159-009-0020-6 | bibcode=2009A&ARv..17..251S }}</ref>
<ref name=aar17_3_251>{{citation | last1=Strassmeier | first1=Klaus G. | title=Starspots | journal=The Astronomy and Astrophysics Review | volume=17 | issue=3 | pages=251–308 |date=September 2009 | doi=10.1007/s00159-009-0020-6 | bibcode=2009A&ARv..17..251S }}</ref>

⚫
<ref name=Holmberg2009>{{citation
⚫
| display-authors=1 | last1=Holmberg | first1=J.
| last2=Nordström | first2=B. | last3=Andersen | first3=J.
| title=The Geneva-Copenhagen survey of the solar neighbourhood. III. Improved distances, ages, and kinematics
⚫
| volume=501 | issue=3 |date=July 2009 | pages=941–947
⚫
| journal=Astronomy and Astrophysics
⚫
| doi=10.1051/0004-6361/200811191 | bibcode=2009A&A...501..941H
⚫
| arxiv=0811.3982 | postscript=. }}</ref>


<ref name=aj628_1_L69>{{cite journal | title=The Age of AB Dor | journal=Astrophysical Journal | date=2005 | volume=628 | issue=1 | pages=L69–L72 | doi=10.1086/432617 | author1=K. L. Luhman | author2=John R. Stauffer | author3=E. E. Mamajek | name-list-format=vanc | bibcode=2005ApJ...628L..69L|arxiv = astro-ph/0510665 }}</ref>
<ref name=aj628_1_L69>{{cite journal | title=The Age of AB Dor | journal=Astrophysical Journal | date=2005 | volume=628 | issue=1 | pages=L69–L72 | doi=10.1086/432617 | author1=K. L. Luhman | author2=John R. Stauffer | author3=E. E. Mamajek | name-list-format=vanc | bibcode=2005ApJ...628L..69L|arxiv = astro-ph/0510665 }}</ref>
Line 112: Line 122:
| issue=5832 | page=1 | date=May 2008
| issue=5832 | page=1 | date=May 2008
| bibcode=2008IBVS.5832....1I | postscript=. }}</ref>
| bibcode=2008IBVS.5832....1I | postscript=. }}</ref>

⚫
<ref name=Torres2006>{{citation
⚫
| display-authors=1
| last=Torres | first=C. A. O. | last2=Quast | first2=G. R.
| last3=Da Silva | first3=L. | last4=De La Reza | first4=R.
| last5=Melo | first5=C. H. F. | last6=Sterzik | first6=M.
| title=Search for associations containing young stars (SACY). I. Sample and searching method
⚫
| journal=[[Astronomy and Astrophysics]]
⚫
| volume=460 | issue=3 | date=December 2006 | pages=695–708
⚫
| doi=10.1051/0004-6361:20065602 | bibcode=2006A&A...460..695T
⚫
| arxiv=astro-ph/0609258 | postscript=. }}</ref>


}}
}}
Line 118: Line 139:
* http://jumk.de/astronomie/special-stars/ab-doradus.shtml
* http://jumk.de/astronomie/special-stars/ab-doradus.shtml
* {{cite web | url = http://simbad.u-strasbg.fr/sim-id.pl?protocol=html&Ident=AB+Doradus | title = HD 36705 -- Rotationally variable Star | publisher = SIMBAD: Centre de Données astronomiques de Strasbourg | accessdate = 2006-08-25 }}
* {{cite web | url = http://simbad.u-strasbg.fr/sim-id.pl?protocol=html&Ident=AB+Doradus | title = HD 36705 -- Rotationally variable Star | publisher = SIMBAD: Centre de Données astronomiques de Strasbourg | accessdate = 2006-08-25 }}
* {{cite web|date=1998-11-05 |url=http://wwwadd.zah.uni-heidelberg.de/datenbanken/aricns/cnspages/4c05660.htm |title=4C05660 |publisher=Astronomisches Rechen-Institut Heidelberg |accessdate=2006-08-25 }}
* {{cite web | url = http://www.sciencedaily.com/releases/2007/06/070619125635.htm | title = Detecting Extra-solar Planets}}
* {{cite web | url = http://www.sciencedaily.com/releases/2007/06/070619125635.htm | title = Detecting Extra-solar Planets}}
* {{CelestialRefEx}}
* {{CelestialRefEx}}

Revision as of 12:02, 19 July 2017

This article is about the star system in the constellation Doradus. For the group of stars that moves with it, see AB Doradus moving group.
AB Doradus

AB Doradus with the orbit of C in yellow
Observation data
Epoch J2000      Equinox J2000
Constellation Dorado
Right ascension 05h 28m 44.8489s[1]
Declination −65° 26′ 54.946″[1]
Apparent magnitude (V) 6.98−7.06[2] / 13.0[3]
Characteristics
AB Dor AC
Spectral type K0V[4] + M8
U−B color index +0.37
B−V color index +0.86±0.02[2]
Variable type Flare star
AB Dor B
Spectral type M5 + M5-6[5]
Astrometry
Radial velocity (Rv)32.40 ± 2.2[6] km/s
Proper motion (μ) RA: 33.16[7] mas/yr
Dec.: 150.83[7] mas/yr
Parallax (π)65.93 ± 0.57 mas[7]
Distance49.5 ± 0.4 ly
(15.2 ± 0.1 pc)
Orbit[5]
PrimaryAB Dor Ba
CompanionAB Dor Bb
Period (P)0.986 ± 0.008 yr
Semi-major axis (a)0.052 ± 0.002″
Eccentricity (e)0.6 ± 0.1
Inclination (i)121 ± 5°
Longitude of the node (Ω)270 ± 15°
Periastron epoch (T)2003.68 ± 0.05
Argument of periastron (ω)
(secondary)		54 ± 20°
Orbit
CompanionAB Doradus C
Period (P)11.75 yr
Semi-major axis (a)2.3 AU″
Details
AB Dor A
Mass0.86[8] M☉
Radius0.96±0.06[8] R☉
Temperature5,250[9] K
Rotation0.5148 days[9]
Age50[10] Myr
AB Dor Ba
Mass0.28 ± 0.05[5] M☉
AB Dor Bb
Mass0.25 ± 0.05[5] M☉
Other designations
AB Dor, CD−65° 332, HD 36705, HIP 25647
Database references
SIMBADdata
ARICNSdata

AB Doradus is a pre-main-sequence quadruple[5] star system in the constellation Dorado. The primary is a flare star that shows periodic increases in activity.

The primary star in this system spins at a rate 50 times that of the Sun, and consequently has a strong magnetic field.[11] It has a greater number of star spots than the Sun. These can cause the luminosity of the star to appear to vary over each orbital cycle. Measurements of the spin rate of this star at its equator have shown that it varies over time due to the effect of this magnetic field.[12]

The system has four components consisting of a pair of binary star systems separated by an angle of about 9″.[5] The binary star AB Doradus Ba/Bb orbits the primary AB Doradus A at an average distance of 135 astronomical units (AUs). AB Doradus C, is a close-in companion that orbits the primary at a distance of 2.3 AU, and has an orbital period of 11.75 years. The latter star is among the lowest-mass stars ever found. At an estimated mass 93 times Jupiter's, it is near the limit of 75–83 Jupiter masses below which it would be classified as a brown dwarf.[13]

This system is a member of the eponymous AB Doradus Moving Group, a loose stellar association of about 30 stars that are all approximately the same age and moving in the same general direction.[14] It is likely that all of these stars formed in the same giant molecular cloud.

References

  1. ^ a b Gaia Collaboration (2016). "Gaia Data Release 1". Astronomy & Astrophysics. 595: A2. arXiv:1609.04172. Bibcode:2016A&A...595A...2G. doi:10.1051/0004-6361/201629512.
  2. ^ a b Innis, J. L.; et al. (May 2008), "Recent CCD Photometry of AB Dor, and a Comment on the Long-term Activity Cycle", Information Bulletin on Variable Stars (5832): 1, Bibcode:2008IBVS.5832....1I.
  3. ^ "NAME AB Dor B". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 19 July 2017.
  4. ^ Torres, C. A. O.; 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.
  5. ^ a b c d e f Azulay, R.; et al. (June 2015), "Dynamical masses of the low-mass stellar binary AB Doradus B", Astronomy & Astrophysics, 578: 9, arXiv:1504.02766, Bibcode:2015A&A...578A..16A, doi:10.1051/0004-6361/201525704, A16.
  6. ^ Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065.
  7. ^ a b c van Leeuwen, F.; et al. (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.
  8. ^ a b Drake, Jeremy J.; et al. (March 2015), "X-Ray Evidence for a Pole-dominated Corona on AB Dor", The Astrophysical Journal, 802 (1): 11, arXiv:1501.05846, Bibcode:2015ApJ...802...62D, doi:10.1088/0004-637X/802/1/62, 62.
  9. ^ a b Strassmeier, Klaus G. (September 2009), "Starspots", The Astronomy and Astrophysics Review, 17 (3): 251–308, Bibcode:2009A&ARv..17..251S, doi:10.1007/s00159-009-0020-6
  10. ^ K. L. Luhman; John R. Stauffer; E. E. Mamajek (2005). "The Age of AB Dor". Astrophysical Journal. 628 (1): L69–L72. arXiv:astro-ph/0510665. Bibcode:2005ApJ...628L..69L. doi:10.1086/432617. {{cite journal}}: Unknown parameter |name-list-format= ignored (|name-list-style= suggested) (help)
  11. ^ JR Minkel (2001-12-11). "Shimmying Star May Shed Light on Forces at Work in the Sun". Scientific American. Retrieved 2006-06-25.
  12. ^ A. C. Cameron; J. F. Donati. "Christmas Star Does the Twist". PPARC. Retrieved 2006-08-25. (The AB Dor Picture Gallery)
  13. ^ "Weighing the Smallest Stars". ESO. 2005-01-19. Retrieved 2006-08-13.
  14. ^ B. Zuckerman; I. Song; M. S. Bessell (2005). "The AB Doradus Moving Group". The Astrophysical Journal. 613 (1): L65–L68. Bibcode:2004ApJ...613L..65Z. doi:10.1086/425036. {{cite journal}}: Unknown parameter |name-list-format= ignored (|name-list-style= suggested) (help)

External links

Wikimedia Commons has media related to AB Doradus.
Retrieved from "https://en.wikipedia.org/w/index.php?title=AB_Doradus&oldid=791308345"