AA Tauri

Short description: Star in the constellation Taurus

AA Tauri

A visual band light curve for AA Tauri, adapted from Bouvier et al. (2013).[1] The main plot shows the long term variation, and the inset plot shows the periodic variation after the dramatic dimming in 2011.

Observation data
Equinox J2000.0]] (ICRS)
Constellation | Taurus
Right ascension |  04h 34m 55.42019s[2]
Declination | +24° 28′ 53.0336″[2]
Apparent magnitude (V) | 12.2 to 16.1[3]
Characteristics
Spectral type | K7Ve[4]
Variable type | T Tauri-type?[4]
Astrometry
Radial velocity (Rv)| 16.98±0.04[5] km/s
Proper motion (μ)|  RA: +5.323[2] mas/yr
Dec.: −20.680[2] mas/yr
Parallax (π)| 7.4255 ± 0.0868[2] mas
Distance| 439 ± 5 ly
(135 ± 2 pc)
Details
Mass| 0.76[6] M☉
Radius| 1.81[6] R☉
Luminosity| 0.8[6] L☉
Temperature| 4,060[6] K
Rotational velocity (v sin i)| 12.8±1.1[5] km/s
Age| 2.4[6] Myr
Other designations

AA Tau, GCRV 55202, XEST 25-026, AN 196.1930, GSC 01833-00851, 2MASS J04345542+2428531, CSI+24-04319, MHA 259-17, 2E 0431.8+2422, IRAS 04318+2422, UBV 4396, 2E 1098, IRAS F04318+2422, XEST 25-OM-003[7]

Database references
SIMBAD| data

AA Tauri is a young variable star in the equatorial constellation of Taurus, located in the Taurus-Auriga star-forming region. It is too faint to view with the naked eye, having an apparent visual magnitude that varies from 12.2 down to 16.1.[3] The star is located approximately 439 light-years (135 parsecs) away from the Sun based on parallax, and is drifting further away with a radial velocity of +17 km/s.[5]

The stellar classification for this object is K7Ve,[4] matching a K-type main-sequence star that displays emission features. It is an eruptive variable of the T Tauri type[3] with an estimated age of 2.4 million years. The object has 76% of the mass of the Sun, 181% of the Sun's radius,[6] and is spinning with a projected rotational velocity of 13 km/s.[5] AA Tauri is radiating 80% of the luminosity of the Sun at an effective temperature of 4,060 K.[6]

## Variability

AA Tauri shows brightness variations of one to two magnitudes over an 8.2-day period. The brightness has been described as "roughly constant, interrupted by quasi-cyclic fading episodes".[8] The periodic variations are ascribed to eclipses of the star by a warped dust disk around it.[9]

In 2011, AA Tauri faded by about two magnitudes and has remained at the fainter level since then. The star also became significantly more reddened. The eight-day variations continue, with a maximum brightness now around magnitude 14 and magnitude 16.5 at its faintest. It is theorised that the root cause of this dimness is a warp in the accretion disk, located at a distance of 7.7 AU or more from the centre, that was brought into the line of sight by its elliptical motion around the central star.[1]

## Search for planets

In their 2003 paper, Bouvier et al. invoked the possible presence of a substellar object to explain peculiar and periodic eclipses occurring to the young star every 8.3 days, though they considered it unlikely that such a companion could be responsible for said variability.[8] They inferred a mass of 20 times that of Jupiter for the perturbing object and an orbital separation of 0.08 Astronomical Units. Later studies find no evidence for a planet, instead finding multiple rings with accretion streams between them.[9]

## References

1. ↑ 1.0 1.1 Bouvier, J.; Grankin, K.; Ellerbroek, L. E.; Bouy, H.; Barrado, D. (2013). "AA Tauri's sudden and long-lasting deepening: Enhanced extinction by its circumstellar disk". Astronomy & Astrophysics 557: A77. doi:10.1051/0004-6361/201321389. Bibcode: 2013A&A...557A..77B.
2. ↑ 2.0 2.1 2.2 2.3 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.
3. ↑ 3.0 3.1 3.2 Samus, N. N. et al. (2017). "General Catalogue of Variable Stars". Astronomy Reports. 5.1 61 (1): 80–88. doi:10.1134/S1063772917010085. Bibcode: 2017ARep...61...80S.
4. ↑ 4.0 4.1 4.2 Herbig, G. H. (1977). "Radial velocities and spectral types of T Tauri stars". Astrophysical Journal 214: 747–758. doi:10.1086/155304. Bibcode: 1977ApJ...214..747H.
5. ↑ 5.0 5.1 5.2 5.3 Nguyen, Duy Cuong et al. (February 2012). "Close Companions to Young Stars. I. A Large Spectroscopic Survey in Chamaeleon I and Taurus-Auriga". The Astrophysical Journal 745 (2): 25. doi:10.1088/0004-637X/745/2/119. 119. Bibcode: 2012ApJ...745..119N.
6. ↑ 6.0 6.1 6.2 6.3 6.4 6.5 6.6 Güdel (2007). "The XMM-Newton Extended Survey of the Taurus Molecular Cloud (XEST)". Astronomy and Astrophysics 468 (2): 353–377. doi:10.1051/0004-6361:20065724. Bibcode: 2007A&A...468..353G.
7. ↑ "AA Tau". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=AA+Tau.
8. ↑ 8.0 8.1 Bouvier (2003). "Eclipses by circumstellar material in the T Tauri star AA Tau. II. Evidence for non-stationary magnetospheric accretion". Astronomy and Astrophysics 409: 169–192. doi:10.1051/0004-6361:20030938. Bibcode: 2003A&A...409..169B.
9. ↑ 9.0 9.1 Loomis, Ryan A.; Öberg, Karin I.; Andrews, Sean M.; MacGregor, Meredith A. (2017). "A Multi-ringed, Modestly Inclined Protoplanetary Disk around AA Tau". The Astrophysical Journal 840 (1): 23. doi:10.3847/1538-4357/aa6c63. Bibcode: 2017ApJ...840...23L.

* v
* t
* e

Stars of Taurus

Bayer|

* α (Aldebaran)
* β (Elnath)
* γ (Prima Hyadum)
* δ1 (Secunda Hyadum)
* δ2
* δ3
* ε (Ain)
* ζ (Tianguan)
* η (Alcyone)
* θ1
* θ2
* ι
* κ1
* κ2
* λ
* μ
* ν
* ξ
* ο
* π
* ρ
* σ1
* σ2
* τ
* υ
* φ
* χ
* ψ
* ω1
* ω2

Flamsteed|

* 4 (s)
* 5 (f)
* 6 (t)
* 7
* 9
* 10
* 11
* 12
* 13
* 14
* 16 (Celaeno)
* 17 (Electra)
* 18
* 19 (Taygeta)
* 20 (Maia)
* 21 (Asterope)
* 22 (Asterope II)
* 23 (Merope)
* 24
* 26
* 27 (Atlas)
* 28 (Pleione)
* 29 (u)
* 30 (e)
* 31
* 32
* 33
* 36
* 37 (A1)
* 39 (A2)
* 40
* 41
* 44 (p)
* 45
* 46
* 47
* 48
* 51
* 53
* 55
* 56
* 57 (h)
* 58
* 60
* 62
* 63
* 66 (r)
* 70
* 71
* 72
* 75
* 76
* 79 (b)
* 80
* 81
* 83
* 84
* 85
* 88 (d)
* 89
* 90 (c)
* 93
* 95
* 96
* 97 (i)
* 98 (k)
* 99
* 101
* 103
* 104 (m)
* 105
* 106 (i)
* 107
* 108
* 109 (n)
* 110
* 111
* 113
* 114 (o)
* 115
* 116
* 117
* 118
* 119
* 120
* 121
* 122
* 125
* 126
* 127
* 128
* 129
* 130
* 131
* 132
* 133
* 134
* 135
* 136
* 137
* 139
* 140
* 44 Eri
* 49 Eri

Variable|

* T
* Y
* Z
* RR
* RV
* RW
* RY
* RZ
* SU
* SV
* SZ
* TU
* UX
* UZ
* VY
* XX
* XZ
* AA
* AH
* BP
* CD
* CI
* CQ
* CT
* CU
* CW
* CY
* DD
* DF
* DG
* DH
* DI
* DL
* DM
* DN
* DO
* DQ
* DR
* DS
* EQ
* EU
* FN
* FS
* FV
* GG
* GI
* GK
* GV
* HK
* HL
* HU
* IK
* V410
* V471
* V473
* V479
* V534
* V624
* V647
* V650
* V710
* V711
* V731
* V766
* V773
* V774
* V781
* V807
* V818
* V819
* V826
* V827
* V827
* V830
* V833
* V834
* V836
* V837
* V892
* V987
* V1038
* V1062
* V1116
* V1137
* V1141
* V1143
* V1156
* V1187
* V1229
* V1232
* V1241 (WX Eri)

HR|

* 1023
* 1028
* 1039
* 1067
* 1085
* 1089
* 1102
* 1103
* 1110
* 1119
* 1137
* 1159
* 1172
* 1183
* 1185
* 1188
* 1201
* 1222
* 1224
* 1233
* 1237
* 1238
* 1253
* 1254
* 1257
* 1279
* 1280
* 1284
* 1295
* 1307
* 1310
* 1315
* 1349
* 1354
* 1358
* 1360
* 1370
* 1385
* 1400
* 1402
* 1403
* 1406
* 1413
* 1425
* 1427
* 1436
* 1442
* 1445
* 1446
* 1448
* 1455
* 1477
* 1480
* 1490
* 1512
* 1517
* 1554
* 1566
* 1575
* 1585
* 1633
* 1642
* 1741
* 1750
* 1755
* 1831
* 1847
* 1860
* 1878
* 1902
* 1921
* 1929
* 1954
* 1997
* 2013
* 2074

HD|

* 21032
* 21585
* 23514
* 23712
* 24040
* 24368
* 24496
* 26292
* 27860
* 28086
* 28375
* 28678
* 29627
* 29647
* 36112
* 37124
* 38263
* 38524
* 285507

Gliese|

* Gliese 176

Other|

* 2MASS J03552337+1133437
* 2MASS J04414489+2301513
* A0535+26
* BD +24 692
* Butterfly star
* CoKu Tau/4
* Crab Pulsar
* Elias 16
* Elias 18
* GD 71
* Haro 6-37
* HBC 379
* HH 30
* HII 686
* HII 1306
* HII 1883
* HII 3163
* HL Tau 76
* HP Tau/G2
* Hubble I 4
* HZ 9
* IRAS 04239+2436
* IRAS 04248+2612
* IRAS 04325+2402
* IRAS 04381+2540
* L1489 IRS
* L1527
* L1551 IRS 5
* L1521F-IRS
* LkCa 15
* MWC 480
* PSR B0525+21
* PSR B0540+23
* PSR J0348+0432
* PSR J0538+2813
* Teide 1
* TMR-1
* TMC-1A
* WD 0346+246
* WISE 0410+1502

* List

0.00

(0 votes)

Original source: https://en.wikipedia.org/wiki/AA Tauri. Read more

|

Retrieved from "https://handwiki.org/wiki/index.php?title=Astronomy:AA_Tauri&oldid=3426149"
*[RA:]: Right Ascension
*[Dec.:]: Declination
*[v]: View this template
*[t]: Discuss this template
*[e]: Edit this template